An ancient iron column: Did "a very thin layer of phosphorus formed, between the rust and the fresh metal and basically stop… it from rustingany more"
What do you need to build a skyscraper?
I was listening to a podcast from the Royal Institution (where Humphrey Davy and Michael Faraday were based). I must confess I had downloaded the 'Recipe for a Skyscraper' episode some time ago but it had been passed over for other titles.
My mistake. In this talk "structural engineer Roma Agrawal delves into the history of the materials that enable immense construction and the developments that have made our structures what they are today. All while noting the accomplishments of key visionary engineers of the past". This proved to be an engaging and fascinating talk.
A 'mega badass engineer'
On her website, Roma Agrawal , "a structural engineer, author and broadcaster, with a physics degree" describes herself as a "mega badass engineer". She is not above being a little mischievous.
The crumbly ages
For example, she has her own take on what historians used to call the 'dark ages', 1
"So, oddly enough, once the Roman empire fell, the use of concrete basically ended for nearly a thousand years, so that we call it the dark ages, or the crumbly ages as I like to call it, because they went back to using slightly older [construction materials], you know, mud and brick and things like that."
Roma Agrawal talking at the Royal Institution
But while the Romans may have championed the use of concrete, the Indians were outperforming them in the production of high quality iron: "The Romans actually used to import Indian steel at the time and they never knew how to make it because that secret was closely guarded…"
Iron is too reactive to be found 'native' but has to be produced by roasting its ores (that contain compounds of iron) with materials that will reduce the iron compounds to iron, and produce, as a by-product, slag – a complex mixtures of substances. The iron produced will contain some slag mixed into the metal unless this is carefully removed. 2
The Delhi column
As an example of the Indian expertise, Roma Agrawal referred to an old iron column near Delhi which "had not rusted" despite having been erected 1500 years ago.3 The column had originally been a stand for a statue of Garuda, the divine winged creature/demigod who acted as the vehicle for Vishnu. Garuda seems to have flown, but the iron column remains.
The (not quite 4) 'rustless wonder' (Srinivasan & Ranganathan, 2013): the Qtub Iron Pillar
Lord Vishnu on his mount Garuda (wood carving). It is thought the iron pillar near Delhi once supported a statue of Garuda.
(Image by waradet from Pixabay)
Iron is the main constituent of alloys known as steels, and by mixing other elements (principally, but not only, carbon) with iron it is possible to create steels with various properties, including corrosion resistance. 2 But iron itself readily rusts. The rust formed when iron corrodes is permeable and crumbly, exposing the unreacted metal beneath, which in turn forms rust that again fails to protect the iron beneath it. So, over time, a piece of iron can simply 'rust away' as the reacted material will simply fall off, or be eroded by weather.
Yet this iron column, erected around the time of the final collapse of the Roman Empire, seems to have survived throughout 'the crumbly ages' and through to the present day. Although, it is not that it never started rusting 4, but rather,
"it did initially rust, but then because of the climate in Delhi, the phosphorus, a very thin layer of phosphorus formed, between the rust and the fresh metal and basically stopped it from rusting any more…"
Roma Agrawal talking at the Royal Institution
Corrosion (as with tarnishing) is a generic term. Corrosion leads to structural damage to metal objects (whereas tarnishing is a surface effect).
Rusting is specific to iron as it refers to the material produced when iron corrodes – i.e., rust.
Unreactive phosphorus?: An alternative conception
Roma Agrawal's claim seems incredible to a chemist or science teacher because phsophorus is a very reactive element, and a very reactive element does not seem a good choice of material to protect iron from reacting! Even if the phosphorus did not itself react with the iron and so corrode it, it would soon react with air. In the laboratory, some forms of phosphorus can burst into flames spontaneously, suggesting it is very unlikely to remain intact very long exposed to the elements in India. Certainly not many centuries.
Sacrificial elements
Now, sometimes a more valuable metal is protected by connecting it physically to a more reactive but less valuable metal which preferentially corrodes. As the metals are in electrical contact, the one that loses electrons and releases cations more readily reacts first. The metal allowed to corrode is called a 'sacrificial' metal. For example, bars of sacrificial metal may be dangled from piers or oil rigs to protect the structural metal. The sacrificial metal will slowly 'dissolve' away into the sea 5 – but not that slowly that it would not need replacing for over a millennium. In any case, phosphorus is a non-metal, where the sacrificial element of the pair needs to be the more electropositive. So, there is no helpful explanation there.
Alumina – when tarnishing prevents corrosion
Aluminium is a more reactive metal than iron, yet does not readily undergo substantive corrosion. This is because the surface of an aluminium object readily reacts with oxygen from the air to form a layer of aluminium oxide (alumina). This then protects the aluminium because the alumina formed is a fairly inert substance (unlike the highly reactive phosphorus), and it forms an impermeable layer (preventing oxygen from the air reaching the metal beneath).
Any layer that were to form on iron protect it from rusting also needs to be impermeable and relatively inert. Unlike reactive phosphorus.
Phosphorus would not protect iron
Phosphorus is a fire hazard that burns to produce toxic fumes. In the laboratory, the direct reaction of iron and phosphorus usually requires heating to initiate reaction. Without active heating, the rate of reaction would be too low for a useful laboratory process. However, a very low rate of reaction would not prevent reaction over the centuries since the iron column was erected.
Even if phosphorus was able to form a layer that coated over the iron, using it as a means to prevent corrosion would be like fireproofing a wooden building by coating it with petroleum jelly (e.g., Vaseline). [A correspondent to the British Dental Journal (Brewer, 2017) warned of "the death of a bedbound patient who smoked following application of E45 cream…a paraffin-based product, the residue of which can act as an accelerant when ignited". Smoking kills. And even more rapidly if you smother yourself in flammable oil products prior to lighting up.]
So, it seems we have a mystery.
Or, Roma Agrawal simply got it wrong.
Or, perhaps, more likely, when Roma Agrawal refers to a 'layer of phosphorus' she is using the term loosely, and is actually referring to something else. That is, the protective layer may contain one or more phosphorus compounds, but not phosphorus – just as a layer of the unreactive aluminium compound alumina stops corrosion, although aluminium itself is reactive. Is this distinction just being pedantic? Not to a science educator.
An elementary misconception
The claim that a layer of phosphorus could protect iron from corrosion is therefore not credible to the scientifically literate, but might seem perfectly reasonable to a person with limited science background. One of the great challenges of learning chemistry is making sense of the set of ideas that:
the compound of an element is a completely different substance to the element itself
the properties of compounds are often quite different (sometimes contrastingly so) to those of the elements the compound was formed from
although the compound does not behave like the elements, and does not 'contain' the elements in any straightforward way, there is a sense in which something of the elements persists in (and so the element may be recovered from) the compound.
So, sodium is a reactive metal that burns in air, and chlorine is a green, toxic, choking gas; and both should be avoided unless taking very careful precautions; yet they react, very energetically, to give the relatively unreactive compound sodium chloride – which people readily use in cooking, and to season their food, and to dissolve in water to gargle with, or to soak tired feet. Chlorine would destroy the lining of your throat. Yet sodium chloride solution (despite its chlorine 'constituent') will help ease a sore throat! Still, the sodium chloride has the potential to be 'separated' into the elements with their dangerous properties intact.
Although the distinction between elements and compounds is a lot easier to understand once students learn about molecules and atoms (at least, if avoiding the alternative conception that compounds comprise of molecules and elements comprise of atoms!) this topic is fraught with complications and hang-overs from historical ideas about atoms (Taber, 2003).
If not a layer of phosphorus?
The chemist or science teacher hearing about a protective 'layer of phosphorus' preventing rusting will immediately thinks this is not viable…but a compound of phosphorus might well have the necessary properties. Indeed, generally, the more reactive the elements, the more stable the compounds they form when reacting.
It seems that the layer that formed on the iron column contains the phosphorus compoundiron hydrogen phosphate hydrate (FePO4·H3PO4·4H2O),
"Several theories have been postulated regarding corrosion resistance of the Delhi iron pillar. Some of those refer to the inherent nature of the construction material, such as the selection of pure iron, presence of slag particles and slag coatings, surface finishing using mechanical operation, phosphate film formation, or the Delhi's climate…
Earlier studies have delineated the formation of crystalline iron hydrogen phosphate hydrate (FePO4·H3PO4·4H2O), 𝛼-, 𝛾-, 𝛿-FeOOH and magnetite in the case of Delhi iron pillar"
Yet this critical, and somewhat counter-intuitive, distinction between elements qua elements and elements as in some sense 'components' (or 'ingredients') of compounds needs to be acquired. Novices have to learn this. A common alternative conception is to assume that the properties of elements are carried over into their compounds.
So, if students hear that
phosphorus is essential in our diet, and that
phosphorus is important for healthy bones and teeth,
they can draw the obvious and reasonable conclusion – that phosphorus must be a pretty innocuous substance as it is part of our bodies and we eat it quite safely in our food. Actually, we need compounds of phosphorus in our food to allow our metabolisms to build and repair tissues that contain phosphorus compounds – and anyone misguided enough to try to eat any actual (elemental) phosphorus risks a nasty burn.
In conclusion, as a science graduate, Roma Agrawal presumably appreciates the key distinction between (i) elements as substances and (ii) elements as chemically combined components of other substances, and, as a structural engineer knowledgeable about different material properties, is using 'layer of phosphorus' as a shorthand for a layer of material that includes one or more phosphorus compounds.
That is fine as long as those hearing her talk appreciate that. Another scientist would likely automatically hear 'phosphorus layer' as meaning 'phosphorus compound containing layer'. A science teacher, however, might suspect that the reference to how "a very thin layer of phosphorus formed, between the rust and the fresh metal and basically stopped it from rusting" is likely to be misunderstood, and indeed to mislead, some listening to the podcast.
Minding your Ps…
One of the sources referred to reported how:
"P is found present in slag whereas the presence of P in iron was not detected within the limit of the analytical techniques used in this study. On the basis of this result, we speculate application of lime and other basic compounds during the iron making process which would have led to the transfer P to slag."
P is the symbol for phosphorus, the element. However, someone with a sufficient scientific background appreciates from the context that references to
P found in slag
P in iron
transfer [of] P to slag
cannot refer to P as phosphorus the element, but rather some compound or compounds of phosphorus. As a reactive element, phosphorus is not found native and so would not be present (as an element) in the raw materials and, in any case, could certainly not survive (as an element) the high temperature conditions of the processes of iron smelting. Therefore the relevant 'context' for reinterpreting 'P' as not standing for the element itself would be any set of circumstances other than the special conditions where phosphorus can be safely stored without risk of reaction.
This is the prerequisite background knowledge that prevents an audience member misinterpreting what must be meant by a "thin layer of phosphorus [sic]" protecting an exposed iron column – as it cannot possibly refer to a thin layer of [actual, elemental] phosphorus.
Sources cited
Anantharaman, T. R. (1997). The iron pillar at Delhi. In S. Ranganathan (Ed.), Iron and Steel Heritage of India (pp. 1-28). Indian Institute of Metals and Tata Steel.
Brewer, E. Patient safety: Paraffin-based products. British Dental Journal223, 620 (2017). https://doi.org/10.1038/sj.bdj.2017.936
Dwivedi, D., Mata, J. P., Salvemini, F., Rowles, M. R., Becker, T., & Lepková, K. (2021). Uncovering the superior corrosion resistance of iron made via ancient Indian iron-making practice. Scientific Reports, 11(1), 4221. doi:10.1038/s41598-021-81918-w
Falk, S. (2020). The Light Ages. A Medieval journey of discovery. Allen Lane.
Srinivasan, S., & Ranganathan, S. (2013). Minerals and Metals Heritage of India. Bangalore: National Institute of Advanced Studies.
1 A simplistic view was that advancing civilisation underwent something of a relapse during the middle ages, until the gains of the classical age (the Greeks, the Romans) were rediscovered in the Enlightenment. Thus, the term 'dark ages' applied to the 'middle ages'.
There were no dark ages: as a matter of fact, they are all dark
with apologies to Pink Floyd
That is clearly a great simplification, and ignores many medieval achievements, as well as being a rather Eurocentric view. Some historians have been seeking to redress this impression: for example, Seb Falk (2020) has renamed this period 'the light ages'.
2 To suggest that steel deliberately contains impurities added to iron could give the impression that iron artefacts are made of purer materials than steel ones. This is misleading. Basic iron smelting produces iron that is impure (sometimes known as 'pig iron') and which can contain quite high levels of impurities. Pig iron typically has a high level of carbon – more than is usually used in steels.
Wrought iron is produced by physical working of pig iron which expels much of the slag content, giving purer iron. Wrought iron has long been widely used in structures, but still does not have a high level of purity.
Alloys are mixtures of different metals, or of metallic elements with other elements. 'Metal' here is ambiguous as it can refer to
an electropositive element (the usual meaning in chemistry) or
a material with certain properties (the usual meaning in engineering) – i.e., malleable, ductile, high electrical and thermal conductivities, lustre, sonorous.
Steels are metals in the 'materials' sense, but 'chemically' are mixtures of the metallic element iron with other elements.
As the properties of steels are sensitive to the levels of other elements, making steel requires using high quality iron that has been treated to remove most of the impurities. This is similar to doping a semiconductor such as silicon to produce electronic components. Very pure silicon is needed as a starting point, so that just the right amount of a specific dopant can be added.
The Indian iron manufacture of Roman times tended to produce iron with a significant phosphorus content.
3 The column was made of wrought iron,
"The forging of wrought iron seems to have reached its zenith in India in the first millennium AD. The earliest large forging is the famous iron pillar with a height of over 7 m and weight of about 6 tons at New Delhi ascribed to Chandragupta Vikramaditya 400- 450 CE… the absence of corrosion is linked to the composition, the high purity of the wrought iron and the phosphorus content and the distribution of slag."
Srinivasan & Ranganathan, 2013
4 The lack of rusting may have been exaggerated,
"The first impression in 1961 was that the portion of the Pillar below the earth was "superficially rusted". However, on detailed examination, the buried portion of the Pillar was found covered with thick crusts of rust and, in fact, copious rust scales could be collected, ranging in thickness from a few millimeters (mm) to no less than 15 mm in some portions. Further, the bulbous base of the Pillar was found riddled with numerous cavities and hollows caused by deep corrosion and mineralization of the iron.
Anantharaman, 1997
Even so, the survival of an iron column exposed to weathering for this length of time is still worthy of note.
5 I thought I should put 'dissolve' into 'scare quotes' here. Corrosion is a chemical change, whereas dissolving refers to what is generally considered a physical change. As the sacrificial metal reacts, it releases cations into solution in the sea, in much the same was as, say, dissolving salt releases sodium ions when common salt is added to water. The metal reacts and enters solution – dissolves, if you are comfortable with that word in this context.
it seems good training for a scientist to always read accounts of science with a critical filter primed to notice figurative language and to check that the communication can be understood in a non-metaphorical way
When water is poured from a bottle or other container the stream of liquid can take up complex shapes. In particular, it has long been noted how the stream can appear to have the shape of a chain or string of beads, with the flow seeming to be wider in some places that others.
A stream of poured water does not form a perfect cylinder – something that physics should be able to explain.
(Image by tookapic from Pixabay)
This is just the kind of thing that physicists think they should be able to explain…using physics. An article in Physics World (Jarman, 2022) reports some recent work on just this outstanding problem,
"If you pour water out of a bottle, the liquid stream will often adopt a chain-like structure….At the heart of the effect is the non-cylindrical profile of the jet as it emerges. To minimize surface tension, the jet tries to become a cylinder, but this motion overshoots and results in an oscillation in the profile shape."
What intrigued me here was the choice of phrasing: "To minimize surface tension, the jet tries to become a cylinder…". This language could be considered to reflect teleology, and even anthropomorphism.
Teleology?
Teleological explanations are those that explain something in terms of some kind of endpoint. Something happens in order to bring about some specific state of affairs. The sun shines to allow us to find our way. Plants produce oxygen so we can breathe. That is, there is seen to be purpose in nature, something that is characteristic of mythical and supernatural thinking. In science, teleological explanations are strictly considered a kind of pseudo-explanation – something that has the form of an explanation, but does not really explain anything. Sometimes we find apparently teleological explanations in science because they are being used as a kind of shorthand. For example, if we know that science suggests entropy always increases in processes, we might interpret a scientist's comment that something happens 'in order to increase entropy' to be a loose (or lazy) way of saying that some suggested mechanism or action is considered likely because it is consistent with the assumption that entropy will increase.
Here it is suggested that the odd shape is formed in order "to" minimise surface tension. Scientists have observed that many phenomena (such as rain forming roundish drops) can be explained in terms that surface tension tends to be minimised (cf. entropy tends to increase, objects tend to roll down hills, people tend to get older). But the language here might suggest minimising surface tension is an end that nature seeks – that would be a teleological explanation.
Although perhaps this is not simple teleology, as it is not that the water forms into the shape it does to minimise surface tension, but something more nuanced is going on – the jet of water is actively trying, but not quite managing, to minimise surface tension.
anthropo… (to do with humans, as in anthropology) …morphism (to do with form, as in morphology, amorphous)
…and anthropomorphism?
Anthropomorphic language refers to non-human entities as if they have human experiences, perceptions, and motivations. Both non-living things and non-human organisms may be subjects of anthropomorphism. Anthropomorphism may be used deliberately as a kind of metaphorical language that will help the audience appreciate what is being described because of its similarly to some familiar human experience. In science teaching, and in public communication of science, anthropomorphic language may often be used in this way, giving technical accounts the flavour of a persuasive narrative that people will readily engage with. Anthropomorphism may therefore be useful in 'making the unfamiliar familiar', but sometimes the metaphorical nature of the language may not be recognised, and the listener/reader may think that the anthropomorphic description is meant to be taken at face value. This 'strong anthropomorphism' may be a source of alternative conceptions ('misconceptions') of science.
So, in our present case, we are told that "the "the jet tries to become a cylinder". This is anthropomorphic, as to try to do something means having a goal in mind and deliberately behaving in a way that it is believed, expected, or – at least – hoped, will lead to that goal. Human beings can try to achieve things. We can perceive our environment, have goals, conceptualise possibilities and means to reach them, and put in practice an intention.
Whether, and, if so, which, animals can try to do things rather than simply following evolved instincts is a debated issue.
Does a dog try to please its human companion by bringing the newspaper?
Does the dolphin try to earn a fish by jumping through a hoop? Perhaps.
Does the salmon try to get to a suitable spawning site ('ground', sic) by swimming upstream?
Does the spider try to make a symmetrical web?
Does the bee try to collect nectar by visiting flowers. Probably not.
Does she try to fertiliser those flowers with pollen to ensure there will be flowers for her to visit in future seasons? Almost certainly not!
Jets of water?
Do jets of water think that being cylindrical is desirable (perhaps because they recognise minimal surface tension as an inherent good?) , and so make efforts to bring this about? Clearly not. So, they do not try to do this. They do not try to do anything. They are not the kind of entities that can try.
So, this language is metaphorical. The reader is meant to read that "the jet tries to become a cylinder" to mean something other than "the jet tries to become a cylinder". Now, often figures of speech are used in science communication because the ideas being communicated are abstract and complex, and metaphorical language that describes the science in more familiar terms makes the text more accessible and increases engagement by the audience/readership.
A question here then, is what "the jet tries to become a cylinder" communicates that was more likely to be inaccessible to the reader. Physics World is the house magazine of the Institute of Physics, which means it is sent to all it members working across all areas of physics. So a broad readership, though largely a readership of physicists.
Tracing the stream back to the source
Another question that occurred to me was whether the reporter (Jarman) was simply reporting the original researchers' (Jordan, Ribe, Deblais and Bonn) ways of communicating their work. That report was in an academic journal, Physical Review Fluids, where formal, technical language would be expected. So, I looked up the paper, to see how the work was described there.
Under a heading of 'phenomenology', Jordan and colleagues explain
"Chain oscillations are most readily observed when the viscosities of the jet and the ambient fluid are low and the interface has a high surface tension. Water jets in air satisfy these criteria, and so it is no surprise that chain oscillations occur in many everyday situations. Deformation and vibration of a jet are capillary phenomena in which surface tension acts to reduce the jet's surface area. If the cross section is not circular, its highly curved portions are pulled inward and its weakly curved portions pushed outward relative to a circular section with the same area. But due to inertia the movement overshoots, with the result that the long and short axes of the section are interchanged. The shape of the section therefore evolves as it moves along the axis of the jet, producing a steady liquid chain when observed in the laboratory frame…"
Jordan, Ribe, Deblais & Bonn, 2022
"The shape of the section therefore evolves as it moves along the axis of the jet, producing a steady liquid chain when observed"
(Image by Kevin Phillips from Pixabay)
(This seemed to be a somewhat different meaning of 'phenomenology' to that sometimes used in science education or social science more generally. Phenomenology looks to explore how people directly experience and perceive the world. Jordan and colleagues include here a good deal of re-conceptualisation and interpretation of what is directly observed. 1 )
The effect Jordan and colleagues describe seems analogous to how a pendulum bob that is released and so accelerated (by gravity) towards the point directly beneath its support (where gravitational potential is minimised) acquires sufficient momentum to overshoot, and swing upwards, beginning an oscillatory motion. Something similar is seen in an ammeter where the needle often overshoots, and initially oscillates around the value of a steady current reading (unless the spring is 'critically damped'). The effect is also made use on in striking a tuning fork.
No need to try
There is no mention here of 'trying', so no clear anthropomorphism. So, this was a gloss added in the report in Physics World, perhaps because anthropomorphic narratives are especially engaging and readily accepted by audiences; perhaps because the reporter needed to rephrase so as not to borrow too much of the original text, or perhaps as part of preparing brief copy to an editorially assigned word length. Or, perhaps Sam Jarman was not even conscious of the anthropomorphism being used, as this seems such a natural way to communicate. 2
Surface tension acting up
Did the original authors avoid teleology? They do write about how "surface tension acts to reduce the jet's surface area?" This could be read as teleological – as there seems to be a purpose or goal in the 'action', even if it is not here presented as a premeditated action. Could any suggestions of such a purpose be avoided?
One response might be that, yes, a physicist might suggest the 'true' description is a mathematical formula (and there are plenty of formulae in Jordan et al's paper) and that a verbal description is necessarily the translation of an objective description into an inherently figurative medium (natural language).
And, of course, this is not some special case. We might read that gravity acts to pull something to the ground or air resistance acts to slow a projectile down and so forth. 'To' may just imply a cause of an outcome, not a purpose.
I think a rewording along the lines "the action of the surface tension reduces the jet's surface area"conveys the same meaning, but is more of a neutral description of a process, avoiding any suggestion that there is a purpose involved.
Reading and interpreting
But does this matter? In teaching young people such as school children, there is evidence that some figurative language that is anthropomorphic or teleological may be understood in those terms, and student thinking may later reflect this. Part of science education is offering learners an insight into how science does seek to (oh, science personified: sorry, scientists seek to) describe in neutral terms and not to rely on nature having inherent goals, or comprising of the actions of sentient and deliberate agents.
The readership of Physics World is however a professional audience of members of the community of inducted physicists who are well aware that, actually, surface tension does not try to do anything; and that minimising surface tension is a common observed pattern, not something set out as a target for physical systems to aim for. These physicists are unlikely to be led astray by the engaging prose of Sam Jarman and will fully appreciate the intended meaning.
That said, there is an intimate bidirectional relationship between our thinking and our speech – our speech reflects our thought pattens, but our language also channels our thinking. So, it seems good training for a scientist to always read accounts of science with a critical filter primed to notice figurative language and to check that the communication can be understood in a non-metaphorical way. That includes checking that our understanding of what we have read is in keeping with scientific commitments to exclude explanations that are framed in terms of nature's end goals, or the deliberate agency of non-sentient 'actors'.
Jarman, S. (2022). Flowing liquid 'chains' are best described by Niels Bohr, not Lord Rayleigh. Physics World, 35(12).
Jordan, D. T. A., Ribe, N. M., Deblais, A., & Bonn, D. (2022). Chain oscillations in liquid jets. Physical Review Fluids, 7(10), 104001. doi:10.1103/PhysRevFluids.7.104001
Notes
1 However, none of us are able to be completely naive observers of the world. As William James long ago pointed out, the un-mediated sensory experience of a newborn is a chaos of noise and shapes and colours and so on. Even recognising another person or the presence of a table is an act of interpretation that we learn.
So, experts in a field do see things others do not. A field palaeontologist sees a fossil fragment where the rest of us see undifferentiated dirt and stones. The biochemist sees a steroid structure in a patterns of lines. The football pundit sees a 4-4-2 formation where the occasional viewers just sees people running around. The experienced poker player sees a 'tell' that others would not notice. The professional musician hears a passage in E minor, when most of us just hear a tune.
2 This kind of language reflects a way of thinking and talking often called 'the natural attitude'. Science can be seen in part as a deliberate move to look beyond the common-sense world of the natural attitude to problematise phenomena that might be readily taken as given.
We may get used to, and simply accept, that ice is cold, fire burns, the Lord/King makes decisions and owns the land (and people!), rivers flow, things fall down, the heretic must die, the sun moves across the sky, etc. – and probably most people did for much of human history – where the critical (scientific) attitude is to always ask 'why?'
"After a lecture on cosmology and the structure of the solar system, James [William James] was accosted by a little old lady.
'Your theory that the sun is the centre of the solar system, and the earth is a ball which rotates around it has a very convincing ring to it, Mr. James, but it's wrong. I've got a better theory,' said the little old lady.
'And what is that, madam?' inquired James politely.
'That we live on a crust of earth which is on the back of a giant turtle.'
Not wishing to demolish this absurd little theory by bringing to bear the masses of scientific evidence he had at his command, James decided to gently dissuade his opponent by making her see some of the inadequacies of her position.
'If your theory is correct, madam,' he asked, 'what does this turtle stand on?'
'You're a very clever man, Mr. James, and that's a very good question,' replied the little old lady, 'but I have an answer to it. And it's this: The first turtle stands on the back of a second, far larger, turtle, who stands directly under him.'
'But what does this second turtle stand on?' persisted James patiently.
To this, the little old lady crowed triumphantly,
'It's no use, Mr. James – it's turtles all the way down.'
Ross, 1967, iv
"The Hindoos [sic] held the earth to be hemispherical, and to be supported like a boat turned upside down upon the heads of four elephants, which stood on the back of an immense tortoise. It is usually said that the tortoise rested on nothing, but the Hindoos maintained that it floated on the surface of the universal ocean. The learned Hindoos, however, say that these animals were merely symbolical, the four elephants meaning the four directions of the compass, and the tortoise meaning eternity." (The Popular Science Monthly, March, 1877; image via Wikipedia)
It's metaphors all the way down
A well-known paper in the journal 'Cognitive Science' is entitled 'The metaphorical structure of the human conceptual system' (Lakoff & Johnson, 1980). What the authors meant by this was that metaphor, or perhaps better analogy, was at the basis of much of our thinking, and so our language.
This links to the so-called 'constructivist' perspective on development and learning, and is of great significance in both the historical development of science and in science teaching and learning. Consider some of the concepts met in a science course (electron, evolution, magnetic flux, hysteresis, oxidation state, isomerism…the list is enormous) in comparison to the kind of teaching about the world that parents engage in with young children:
That is a dog
That is a tree
That is round
This is hot
This is aunty
etc.
Pointing out the names of objects is not a perfect technique – just as scientific theories are always underdetermined by the available data (it is always possible to devise another scheme that fits the data, even if such a scheme may have to be forced and convoluted), so the 'this' that is being pointed out as a treecould refer to the corpse of trees, or the nearest branch, or a leaf, or this particular species of plant, or even be the proper name of this tree, etc. 1
Pointing requires the other person to successfully identify what is being pointed at (Images by Joe {background} and OpenClipart-Vectors {figures} from Pixabay)
But, still, the 'this' in such a case is usually more salient than the 'this' when we teach:
This is an electron
This is reduction
This is periodicity
This is electronegativity
This is a food web
This is a ᴨ-bond
This is a neurotransmitter
etc.
Most often in science teaching we are not holding up a physical object or passing it around, but offering a 'this' which is at best a model (e.g., of a generalised plant cell or a human torso) or a complex linguistic structure (a definition in terms of other abstract concepts) or an abstract representation ('this', pointing to a slope of an a graph, is acceleration; 'this', pointing to an image with an arrangement of a few letters and lines, is a transition state…).
So, how do we bridge between the likes of dogs and trees on one hand and electrons and the strong nuclear force on the other (so to speak!)? The answer is we build using analogy and we talk about those constructions using a great deal of metaphor.2 That is, we compare directly, or indirectly, with what we can experience. This refers to relationships as well as objects. We can experience being on top of, beneath, inside, outside, next to, in front of, behind, near to, a long way from (a building, say – although hopefully not beneath in that case), and we assign metaphorical relationships in a similar way to refer to abstract scenarios. (A chloroplast may be found in a cell, but is sodium found in (or on) the periodic table? Yes, metaphorically. And potassium is found beneath it!)
In a wall, the bricks on the top layer are supported by the bricks in the layer beneath – but those are in turn supported by those beneath them.
In building, we have to start at the foundations, and build up level by level. The highest levels are indirectly supported by the foundations.
(Image by OpenClipart-Vectors from Pixabay)
In science, we initially form formal concepts based on direct experience of the world (including experience mediated by our interventions, i.e., experiments), and then we build more abstract concepts from those foundational concepts, and then we build even more abstract concepts by combining the abstract ones. In the early stages we refine 'common sense' or 'life-world' categories into formal concepts so we can more 'tightly' (and operationally, through standard procedures) define what count as referents for scientific terms (Taber, 2013). So, the everyday phenomenon of burning might be reconceptualised as combustion: a class of chemical reactions with oxygen.
This is not just substituting a technical term, but also a more rigid and theoretical (abstract) conceptualisation. So, in the 'life-world' we might admit the effects of too much sunshine or contact with a strong acid within the class of 'burning' by analogy with the effect of fire (it hurts and damages the skin); but the scientific categorisation is less concerned with direct perception, and more with explanation and mechanism. So, iron burning in chlorine (in the absence of any oxygen) is considered combustion, but an acid 'burn' is not.
This is what science has done over centuries, and is also what happens in science education. So, one important tool for the teacher is concept analysis, where we check which prerequisite concepts need to be part of a student's prior learning before we introduce some new concept that is built upon then (e.g., do not try to teach mass spectroscopy before teaching about atomic structure, and do not teach about atomic structure before introducing the notion of elements; do not try to teach about the photoelectric effect to someone who does not know a little about the structure of metals and the nature of electromagnetic radiation.)
This building up of abstract concepts, one on another, is reflected in the density of metaphor we find in our language. (That is a metaphorical 'building', metaphorically placed one upon another, with a metaphorical 'density' which is metaphorically 'inside' the language and which metaphorically 'reflects' the (metaphorical) building process! You can 'see' (a metaphor for understand) just how extensive (oops, another metaphorical reference to physical space) this is. Hopefully, the (metaphorical) 'point' is (metaphorically) 'made', and so I am going to stop now, before this gets silly. 3
A case study of using language in science communication: the death of stars
Rather, I am going to discuss some examples of the language used in a single science programme, a BBC radio programme/podcast in the long-running series 'In Our Time' that took as its theme 'The Death of Stars'. The programme was hosted by Melvyn Bragg, and The Lord Bragg's guests were Professors Carolin Crawford (University of Cambridge), the Astronomer Royal Martin Rees (University of Cambridge) and Mark Sullivan (University of Southampton). This was an really good listen (recommended to anyone with an interest in astronomy), so I have certainly not picked it out to be critical, but rather to analyse the nature of some of the language used from the perspective of how that language communicates technical ideas.
An episode of 'In Our Time' on 'The Death of Stars' "The image above is of the supernova remnant Cassiopeia A, approximately 10,000 light years away, from a once massive star that died in a supernova explosion that was first seen from Earth in 1690"
A science teacher may be familiar with stars being born, living, and dying – but how might a young learner, new to astronomical ideas, make sense of what was meant?
Now there is already a point of interest in the episode title. Are stars really the kind of entities that can die? Does this mean they are living beings prior to death?
There are a good many references in the talk of these three astronomers in the episode that suggests that, in astronomy at least, stars do indeed live and die. That is, this does not seem to be consciously used as a metaphor – even if the terminology may have initially been introduced that way a long time ago. The programme offered so much material on this theme, that I have separated it out for a post of its own:
"So, in the language of astronomy, stars are born, start young, live; sometimes living alone but sometimes not, sometimes have complicated lives; have lifetimes, reach the end of their lives, and die, so, becoming dead, eventually long dead; and indeed there are generations of stars with life-cycles."
In this post I am going to consider some of the other language used.
Making the unfamiliar familiar
Language is used in science communication to the public, as it is in teaching, to introduce abstract technical ideas in ways that a listener new to the subject can make reasonable sense of. The constructivist perspective on learning tells us that meaning is not automatically communicated from speaker (or author or teacher) to listener (or reader or student). Rather, a text (spoken or written, or even in some other form – a diagram, a graph, a dance!) has to be interpreted, and this relies on the interpretive resources available to the learner. 4 The learner has to relate the communication to something familiar, and the speaker can help by using ways to make the new idea seem like something already familiar.
This is why it it is so common in communicating science to simplify, to use analogies and similes, to gesture, to use anthropomorphism and other narrative devices. There was a good deal of this in the programme, and I expect I have missed some examples. I have divided my examples into
simplifications: where some details are omitted so not to overburden the listener;
anthropomorphism: where narratives are offered such that non human entities are treated as if sentient actors, with goals, that behave deliberately;
analogies where an explicit comparison is made to map a familiar concept onto the target concept being introduced; 5
similes and metaphors: that present the technical material as being similar to something familiar and everyday.
Simplification
Simplification means ignoring some of the details, and offering a gloss on things. The details may be important, but in order to get across some key idea it is introduced as a simplification. Progress in understanding would involve subsequently filling in some details to develop a more nuanced understanding later.
In teaching there are dangers in simplification, as if the simplified idea is readily latched onto (e.g., there are two types of chemical bonds: ionic and covalent) it may be difficult later to shift learners on in their thinking. This may mean that there is a subtle balance to be judged between
giving learners enough time to become comfortable with the novel idea as introduced in a simplified form,
and
seeking to develop it out into a more sophisticated account before it become dogma.
In a one-shot input, such as a public lecture or appearance in the media, the best a scientist may be able to do is to present an account which is simple enough to understand, but which offers a sense of the science.
Simplification: all elements/atoms are formed in stars
When introducing the 'In Our Time' episode, Lord Bragg suggested that
"…every element in our bodies, every planet, was made in one of those stars, either as they burned, or as they exploded".
Clearly Melvyn cannot be an expert on the very wide range of topics featured on 'In our time' but relies on briefing notes provided by his guests. Later, in the programme he asks Professor Rees (what would clearly be considered a leading question in a research context!) "Is the sun recycled from previous dead stars?"
"Yes it is because we believe that all pristine material in the universe was mainly just hydrogen and helium, and all the atoms we are made of were not there soon after the big bang. They were all made in stars which lived and died before our solar system formed. And this leads to the problem of trying to understand more massive stars which have more complicated lives and give rise to supernovae…
The cloud from which our solar system formed was already contaminated by the debris, from earlier generations of massive stars which had lived and died more than say five billion years ago so we're literally the ashes of those long dead stars or if you are less romantic we're the nuclear waste from the fuel that kept those old stars shining."
Prof. Martin Rees
There is a potential for confusion here.
"…all the atoms we are made of were not there soon after the big bang. They were all made in stars which lived and died before our solar system formed…"
seems to be meant to convey something like
not all the atoms we are made of were there soon after the big bang. [Some were, but the rest/others] were all made in stars which lived and died before our solar system formed…
A different interpretation (i.e., that all atoms/elements are formed in stars) might well be taken, given Lord Bragg's introductory comments.
Professor Rees referred to how "…the idea that the elements, the atoms we are made of, were all synthesised in stars…" first entered scientific discourse in 1946, due to Fred Hoyle, and to
"this remarkable discovery that we are literally made of the ashes of long dead stars"
Prof. Martin Rees
Before the first star formation, the only elements present in the universe were hydrogen and helium (and some lithium) and the others have been produced in subsequent high energy nuclear processes. Nuclear fusion releases energy when heavier nuclei are formed from fusing together lighter ones, up to iron (element 56).
Forming even heavier elements requires an input of energy from another source. It was once considered that exploding stars, supernovae, gave rise to the conditions for this, but recently other mechanisms have been considered: and Prof. Sullivan described one of these:"we think these combining neutron stars are the main sites where heavy elements like strontium or plutonium, perhaps even gold or silver, these kinds of elements are made in the universe in these neutron stars combining with each other".
A human body includes many different elements, though most of these in relatively small amounts. Well represented are oxygen, carbon, calcium, and nitrogen. These elements exist because of the processes that occur in stars. However, hydrogen is also found in 'organic' substances such as the carbohydrates, proteins, and fats found in the human body. Typically the molecules of these substances contain more hydrogen atoms than atoms of carbon or any other element.
substance
formula
glucose (sugar)
C6H12O6
leucine (amino aid)
C6H13NO2
leukotriene B4 (inflammatory mediator)
C20H32O4
thymine (nucleobase)
C5H6N2O2
adreneline (hormone)
C9H13NO3
insulin (hormone)
C257H383N65O77S6
cholesterol (lipid)
C27H46O
cobalamin (vitamin B12)
C63H88CoN14O14P
formulae of some compounds found in human bodies
The body is also said to be about 60% water, and water has a triatomic molecule: two hydrogen atoms to one of oxygen (H2O). That is, surely MOST of "the atoms we are made of" are hydrogen, which were present in the universe before any stars were 'born'.
So, it seems here we have a simplification ("every element in our bodies…was made in one of those stars, either as they burned, or as they exploded"; "atoms we are made of … were all made in stars") which is contradicted later in the programme. (In teaching, it is likely the teacher would feel the need to draw the learner's attention to how the more detailed information was actually developing an earlier simplification, and not leave a learner to work this out for themselves.)
Simplification: mass is changed into energy
Explaining nuclear fusion, Prof. Crawford suggested that
"Nuclear fusion is when you combine nuclei of elements to form heavier elements, and when you do this there is a loss of mass, which is converted to energy which provides the thermal pressure and that is what counteracts the gravity and stalls the gravitational collapse."
Prof. Carolin Crawford
This seems to reflect a common alternative conception ('misconception') that, in nuclear processes, mass is converted to energy. This is often linked to Albert Einstein's famous equation E = mc2.
Actually, as discussed before here, this is contrary to the scientific account. The equation presents an equivalence between mass and energy, but does not suggest they can be inter-converted. In nuclear fusion, the masses of the new nuclei are very slightly less than the masses of the nuclei which react to form them (the difference is known as the mass defect), but this is because this omits some details of the full description of the process. If the complete process is considered then there is no loss of mass, just a reconfiguration of where the mass can be located.
Although the 4He formed has slightly less mass than four 1H; the positrons, neutrinos and gamma rays produced all have associated (energy and) mass, so that overall there is conservation of mass.
This is a bit like cooking some rice, and finding that when the rice is cooked the contents of the saucepan had slightly less weight than when we started – as some of the water we began with has evaporated and is no longer registering on our balance. In a similar way, if we consider everything that is produced in the nuclear process, then the mass overall is conserved.
As E = mc2 can be understood to tell us that mass follows the energy (or vice versa) we should expect mass changes (albeit very, very small ones) whenever work is done: when we climb the stairs, or make a cup of tea, or run down a mobile 'phone 'battery' (usually a cell?) – but mass is always conserved when we consider everything involved in any process (such as how the 'phone very, very slightly warms -and so very marginally increases the mass of – the environment).
Despite the scientific principles of conservation of energy and conservation of mass always applying when we make sure we consider everything involved in a process, I have mentioned on this site another example of an astrophysicist suggesting mass can be converted into energy: "an electron and the positron, and you put them together, they would annihilate…they would annihilate into energy" (on a different episode of 'In Our Time': come on Melvyn…we always conserve mass).
Perhaps this is an alternative conception shared by some professional scientists, but I wonder if it sometimes seems preferably to tell the "mass into energy" narrative because it is simpler than having to explain the full details of a process – which is inevitably a more complex story and so will be more difficult for a novice to take in. After all, the "mass into energy" story is likely to seem to fit with a listener's interpretive resources, as E=mc2is such a famous equation that it can be assumed that it will be familiar to most listeners, even if only a minority will have a deep appreciation of how the equivalence works.
Anthropomorphic narratives
In science learning, anthropomorphism is (to borrow a much used metaphor) a double edged sword that can cut both ways. Teachers often find that using narratives that present inanimate entities which are foci of science lessons as if they are sentient beings with social lives and motivations engages learners and triggers mental images that a student can readily remember. So, students may recall learning about what happens at a junction in a circuit in terms of a story about an electron that had to make a decision about which way to go – perhaps she took one branch while her friend tried another? They recall that covalent bonds are the 'sharing' of electrons between atoms, and indeed that atoms want, perhaps even need, to fill their electron shells, and if they manage this they will be happy.
The danger here is that for many students such narratives are not simply useful ways to get them thinking about the science concepts (weak anthropomorphism) but seem quite sufficient as the basis of explanations (strong anthropomorphism) – and so it may become difficult to shift them towards more canonical accounts. They will then write in tests that chemical reactions occur because the atoms want full shells, or that only one electron can be removed from a sodium atom because it then has a full shell. (That is, a force applied to an electron in an electric field is seen as irrelevant compared with the atom's desires. These are genuine examples reflecting what students have said.)
However, there is no doubt that framing scientific accounts within narratives which have elements of human experience as social agent does seem to help make these ideas engaging and accessible. Some such anthropomorphism is explicit, such as when gas molecules (are said to) like to move further apart, and some is more subtle by applying terms which would normally be used in relation to human experiences (not being bothered; chomping; escaping…).
What gravity did next
Consider this statement:
"All stars have the problem of supporting themselves against gravitational collapse, whether that is a star like our sun which is burning hydrogen into helium, and thus providing lots of thermal pressure to stop collapse, or whether it is a white dwarf star, but it does not have any hydrogen to burn, because it is an old dead star, fading away, so it has another method to stop itself collapsing and that is called degeneracy pressure. So, although a white dwarf is very dense, gravity is still trying to pull that white dwarf to be even denser and even denser."
Prof. Mark Sullivan
There is an explicit anthropomorphism here: from the scientific perspective gravity is nottrying to pull the white dwarf to be even denser. Gravity does not try to do anything. Gravity is not a conscious agent with goals that it 'tries' to achieve.
However, there is also a more subtle narrative thread at work – that a star has the problem of supporting itself, and it seems that when its first approach to solving this problem fails, it has a fallback method "to stop itself collapsing". But the star is just a complex system where various forces act and so processes occur. A star is not the kind of entity that can have a problem or enact strategies to achieve goals. Yet, this kind of language seems to naturally communicate abstract ideas though embedding them within an accessible narrative.
Star as moral agents
In the same way, a star is not the type of entity which can carry out immoral acts, but
"A star like our sun will never grow in mass, because it lives by itself in space. But most stars in the universe don't live by themselves, they live in what are called binary systems where you have two stars orbiting each other, rather than just the single star that we have as the sun. They are probably born with different masses, and so they evolve at different speeds and one will become a white dwarf. Now the physics is a bit complicated, but what can happen, is that that white dwarf can steal material from its companion star."
Prof. Mark Sullivan
The meaning here seems very clear, but again there are elements of using an anthropomorphic narrative. For one star to steal material from another star, that material would have to first belong to that other star, and its binary 'partner' would have to deliberately misappropriate that material knowing it belongs to its 'neighbour' (indeed, "companion").
Such a narrative breaks down on analysis. If we were to accept that the matter initially belongs to the first star (leaving aside for the moment what kind of entities can be considered to own property) then given that the material in a star got to be there through mutual gravitational attraction, the only obvious basis for ownership is that that matter has become gravitationally bound as part of that star.
If we have no other justification than that (as in the common aphorism, possession is nine points of the law), then when the material is transferred to another star because its gravitational field gives rise to a net force causing the matter to become gravitationally bound to a different star, then we should simply consider ownership to have changed. There is no theft in a context where ownership simply depends on pulling with the greater force. Despite this, we readily accept an analogy from our more familiar human social context and understand that (in a metaphorical sense) one star has stolen from another!
Actually, theft can only be carried out by moral agents – those who have capacity to intend to deprive others of their property
"A person [sic] is guilty of theft if he dishonestly appropriates property belonging to another with the intention of permanently depriving the other of it; and "thief" and "steal" shall be construed accordingly"
U.K. Theft Act 1968
Generally, these days (though this was not always so), even non-human animals are seldom considered capable of being responsible for such crimes. Admittedly, the news agency Reuters reported that as recently as 2008 "A Macedonian court convicted a bear of theft and damage for stealing honey from a beekeeper", but this seems to have been less a judgement on the ability of the bear (convicted it its absence) to engage in ethical deliberation, and more a pragmatic move that allowed the bee-keeper to be awarded criminal damages for his losses.
But, according to astronomers, stars are not only involved in the petty larceny of illicitly acquiring gas, but observations of exoplanets suggests some stars may even commit more daring, large-scale, heists,
"fairly small rocky planets two or three times the mass of the earth, in quite tight orbits around their star and you can speculate that they were once giant planets like Jupiter that have had the outer gassy layers blasted off and you are left with the rocky core, or maybe those planets were stolen from another star that got too close"
Prof. Carolin Crawford
A ménage à trois?
And there were other suggestions of anthropomorphism. It is not only stars that "don't live by themselves" in this universe,
"Nickel-56 [56Ni] is what's called an iron peak element, so it lives with iron and cobalt on the periodic table…"
Prof. Mark Sullivan
And, it is not only gravity which seems to have preferences:
"And like Mark has described with electrons not wanting to be squeezed, you have neutron degeneracy pressure. Neutrons don't like to be compressed, at some point they resist it."
Prof. Carolin Crawford
Neither electrons nor neutrons actually have any preferences: but this is an anthropomorphic metaphor that efficiently communicates a sense of the natural phenomena. 'Resist' originally had an active sense as in taking a stand, but today would not necessarily be understood that way. Wanting and liking (or not wanting and not liking), however, strictly only refer to entities that can have desires and preferences.
Navigating photons
Professor Rees explained why some imploding stars are not seen as very bright stars that fade over years, but rather observed through extremely intense bursts of high energy radiation that fade quickly,
"The energy in the form of ordinary photons, ordinary light, that's arisen in the centre of a supernova, diffuses out and takes weeks to escape, okay, but if the star is spinning, then it will be an oblate spheroid, it will have a minor axis along the spin axis, and so the easy way out is for the radiation not to diffuse through but to find the shortest escape route, which is along the spin axis, and I mention this because gamma ray bursts are … when a supernova occurs but because the original star was sort of flattened there is an easy escape route and all the energy escapes in jets along the spin axis and so instead of it diffusing out over a period of weeks, as it does in a supernova, it comes out in a few seconds."
Prof. Martin Rees
Again, the language used is suggestive. Radiation is not just emitted by the star, but 'escapes' (surely a metaphor?). The phrasing "an easy way out" implies something not being difficult. Inanimate entities like photons do not actually (literally) find anything difficult or easy. Moreover, the radiation might "find the shortest escape route": language that does not reflect a playing out of physical forces but an active search – only a being able to seek can find. Yet, again, the language supports an engaging narrative, 'softening' the rather technical story by subtly reflecting a human quest.
Professor Rees also referred to how,
"when those big stars face a crisis they blow off their outer layers"
Prof. Martin Rees
again using phrasing which seems to present the stars as deliberate actors – they actively "blow off" material when they "face a crisis". A crisis is (or at least was originally) a point where a decision needs to be made. A star does not reach the critical point where it reluctantly decides it needs to shed some material – but rather is subject to changing net forces as the rate of heat generation from nuclear processes starts to decrease.
A sense of anthropomorphic narrative also attaches to Professor Crawford's explanation of how more massive stars process material faster,
"…more massive stars … actually have shorter lifetimes …they have to chomp through their fuel supply so furiously that they exhaust it more rapidly
Prof. Carolin Crawford
'Chomping', a term for vigorous eating (biting, chewing, munching), is here a metaphor, as a star does not eat – as pointed out in the companion piece, nutrition is a characteristics feature of living things, but does not map across to stars even if they are described as being born, living, dying and so forth. To be furious is a human emotional response: stars may process their remaining hydrogen quickly, but there is no fury involved. Again, though, the narrative, perhaps inviting associated mental imagery, communicates a sense of the science.
Laid-back gas
Another example of anthropomorphism was
"…if you have a gas cloud that's been sitting out in space for billions of years and has not bothered to contract because it's been too hot or it's too sparse…"
Prof. Carolin Crawford
This is an interesting example, as Prof. Crawford explicitly explains here that the gas cloud has not contracted because of the low density of material (so weak gravitational forces acting on the particles) and/or the high temperature (so the gas comprises of energetic, so fast moving, particles), so the suggestion that the material cannot be bothered (implication: that the 'cloud' operates as a single entity, and is sentient if perhaps a little lazy) does not stand in place of a scientific explanation, but rather simply seems to be intended to 'soften' (so to speak) the technical nature of the language used.
Analogy
An analogy goes beyond a simile or metaphor because there is some kind of structural mapping to make it explicit in what way or ways the analogue is considered to be like the target concept. 5 (Such as when explaining mass defect in relation to the material lost from the saucepan when cooking rice!)
A potential teaching analogy to avoid alternative conceptions about mass defect in nuclear processes
So, Prof. Rees suggests that scientists can test their theories about star 'life cycles' by observation, even though an individual star only moves through the process over billions of years, and uses an analogy to a more familiar everyday context:
"We can test our theories, not only because we understand the physics, but because we can look at lots of stars. It is rather like if you had never seen a tree before, and you wandered around in a forest for a day, you can infer the life cycles of trees, you'd see saplings and big trees, etcetera. And so even though our lifetime is minuscule compared to the lifetime of a stable star, we can infer the population and life cycles of stars observationally and the theory does corroborate that fairly well."
Prof. Martin Rees
This would seem to make the basis of a good teaching analogy that could be discussed with students and would likely link well with their own experiences.
The other explicit analogy introduced by Prof. Rees is one well-known to physics teachers (sometimes in an ice-skater variant),
"If a contracting cloud has even a tiny little bit of spin, if it is rotating a bit, then as it contracts, then just like the ballerina who pulls in her arms and spins faster, then the contracting cloud will start to spin faster…"
Prof. Martin Rees
Stellar similes
I take the difference between a simile and a metaphor as the presence of an explicit marker (such as '…as…',…like…') to tell the listener/reader that a comparison is being made – so 'the genome is the blueprint for the body' would be a metaphor, where 'the genome is like a blueprint for the body' would be a simile.
As if a black hole cuts itself off
So, when Professor Rees describes how a massive black hole forms, he uses simile (i.e., "…as if were…"),
"So, if a neutron star gets above that mass, then it will compress even further, and will become a black hole – it will go on contracting until it, as it were, cuts itself off from the rest of the universe, leaving a gravitational imprint frozen in the space that's left. It becomes a black hole that things can fall into but not come out."
Prof. Martin Rees
There is an element of anthropomorphic narrative (see above) again here, if we consider the choice of active, rather than passive, phrasing
…as it were, cuts itself off from the rest of the universe, compared with
…as it were, becomes cut off from the rest of the universe
This is presented as something the neutron star itself does ("it will compress…become a black hole – it will go on contracting until it, as it were, cuts itself off…") rather than a process occurring in/to the matter of which it is comprised.
As if galaxies drop over the horizon
Prof. Rees uses another simile, when talking of how the expansion of space means that in time most galaxies will disappear from view,
"All the more distant universe which astronomers like Mark [Sullivan] study, galaxies far away, they will all have expanded their distance from us and in effect disappeared over a sort of horizon and so we just wouldn't see them at all. They'd be too faint, rather like …an inside-out black hole as it were, but in this case they moved so far away that we can't see them any more …"
Prof. Martin Rees
The term horizon, originally referring to the extent of what is in sight as we look across the curved Earth, has become widely used in astronomical contexts where objects cease to be in sight (i.e., the event horizon of a black hole beyond which any light being emitted by an object will not be able to leave {'escape!'} the black hole because of the intense gravitation field), but here Prof. Rees clearly marks out for listeners ("…in effect…a sort of…") that he is making a comparison with the familiar notion of a horizon that we experience here on Earth.
There is another simile here, the reference to the expansion of space leading to an effect "rather like…an inside-out black hole as it were" – but perhaps that comparison would be less useful to a listener new to the topic as it uses a scientific idea rather than an everyday phenomenon as the analogue.
Through a glass onion darkly?
Another simile used by Professor Rees was a references to a "sort of onion skin structure". Now 'onion skin' sometimes refers to the hard, dry, outer material (the 'tunic') usually discarded when preparing the onion for a dish. To a science teacher, however, this is more likely to mean the thin layer of epithelial tissue that can be peeled from the scales inside the bulb. These scales, which are potentially the bases of leaves that can grow if the bulb is planted, are layered in the bulb.
The skin is useful in science lessons as it is a single layer of cells, that is suitable for students to dissect from the onion, and mount for microscopic examination – allowing them to observe the individual cells. There is something at least superficially analogous to this in stars. Observations of the Sun show that convection processes gives rise to structures referred to as convection 'cells'.
Convection 'cells' at the Sun's surface (Source: NASA)Onion skin magnified showing individual epithelial cells (Source: Wikimedia commons)
Yet, when Professor Rees' simile is heard in context, it seems that this is not the focus of the comparison:
"…all the nuclear processes which would occur at different stages in the heavy stars…which have this sort of onion skin structure with the hotter inner layers"
Prof. Martin Rees
Very large stars that have processed much of their hydrogen into helium can be considered to have a layered structure where under different conditions a whole sequence of processes are occurring leading to the formation of successively heavier and heavier elements, and ultimately to a build-up of iron near the centre.
The onion model of the structure of a large star (original image by Taken from Pixabay)
When I heard the reference to the onion, this immediately suggested the layered nature of the onion bulb being like the structure of a star that was carrying out the sequence of processes where the products of one fusion reaction become the raw material for the next. Presumably, my familiarity with the layered model of a star led me to automatically make an association with onions which disregarded the reference to the skin. That is, I had existing 'interpretive resources' to understand why the onion reference was relevant, even though the explicit mention of the skin might make the comparison obscure to someone new to the science.
Metaphors – all the way back up?
Some metaphors can easily be spotted (if someone suggests mitochondria are the power stations of the cell, or a lion is King of the jungle), but if our conceptual systems, and our language, are built by layers of metaphor upon metaphor then actually most metaphors are dead metaphors.
That is, an original metaphor is a creative attempt to make a comparison with something familiar, but once the metaphor is widely taken up, and in time becomes common usage and so a part of standard language, it ceases to act as a metaphor and becomes a literal meaning.
This presumably is what has happened with the adoption of the idea that stars are born, live out their lives, and then die: originally it was a poetic use of language, but now among astronomers it reflects an expanded standard use of terms that were once more restricted (born, live, lifetime, die etc.).
"…Stars dived in blinding skies / Stars die / Blinding skies…" Stars die, but only due to artistic license (Artwork from 'Star's die' by Porcupine Tree, photographer: Chris Kissadjekian)
If you see a standard candle…
When Professor Sullivan refers to a "standard candle", this is now a widely used astronomical notion (in relation to how we estimate distances to distant stars and galaxies that are much too far away to triangulate from parallax as the earth changes its position in the solar system) – but at one time this was used as a figure of speech.
Some figures of speech are created in the moment, but never widely copied and adopted. The astronomical community adopted the 'standard candle' such that it is now an accepted term, even though most young people meeting astronomical ideas for the first time probably have very little direct experience of candles. What might once have seemed a blatantly obvious allusion may now need explaining to the novice.
When Sir Arthur Eddington (famous for collecting observations during an eclipse consistent with predictions from relativity theory about the gravitational 'bending' of starlight) gave a public lecture in 1932, he seems to have assumed that his audience would understand the analogy between an astronomer's 'standard candles' (Cepheid variables) and standard candles they might themselves use!
"If you see a standard candle anywhere and note how bright it appears to you, you can calculate how far off it is; in the same way an astronomer observes his [or her] 'standard candle' in the midst of a nebula, notes its apparent brightness or magnitude, and deduces the distance of the nebula"
Eddington, 1933/1987, pp.7-8
This ongoing development in language means that it may not always be entirely clear which terms are still engaged with as if metaphors and which have now become understood as literal. That is, in considering whether some phrase is a metaphor we can ask two questions:
did the author/speaker intend this as a comparison, or do they consider the term has direct literal meaning?
does the reader/listener understand the term to have a literal meaning, or is it experienced as some novel kind of comparison with another context which has to be related back to the focus?
In the latter case we might also think it is important to distinguish between cases where the audience member can decode the intention of the comparison 'automatically' as part of normal language processing – and cases where they would have to consciously deliberate on the meaning. (In the latter case, the interpretation is likely to disrupt the flow of reading, and when listening could perhaps even require the listener to disengage from the communication such that subsequent speech is missed.)
(Metaphorical?) hosts
So, when Prof. Crawford suggests that
"The supernovae, particularly, are of fundamental importance for the host galaxy…"
Prof. Carolin Crawford
her use of the term 'host' is surely metaphorical (at least for a listener– this term is widely used in the literature of academic astronomy 6). A host offers hospitality for a guest. That does not seem to obviously reflect the relationship between a supernova and the galaxy it is found in and is part of. It is not a guest: rather, in Prof. Sullivan's terms we might suggest that star has 'lived its entire life' in that galaxy – it is its galactic 'home'. Despite this comparison not standing up to much formal analysis, I suspect the metaphor can be automatically processed by anyone with strong familiarity with the concept of a host. Precise alignment may not be a strong criterion for effective metaphors.
Another meaning of host refers to a sacrificial victim (as in the host in the Christian Eucharist) which seems unlikely to be the derivation here, but perhaps fits rather well with Prof. Crawford's point. A supernova too close to earth could potentially destroy the biosphere – an unlikely but not impossible event.
(Metaphorical?) bubbles
Professor Crawford described some of the changes during a supernova,
"You have got your iron core, it collapses down under gravity in less than a second, that kind of leaves the outer layers of the star a little behind, they crash down, bounce on the surface of the core, and then there's a shockwave, that propels all this stellar debris, out into space. So, this is part of the supernova explosion we have been talking about, and it carves out a bubble within the interstellar medium."
Prof. Carolin Crawford
There are a number of places here where everyday terms are applied in an unfamiliar context such as 'core', 'bouncing', 'layers' and 'debris'. But the idea of carving a bubble certainly seems metaphorical, if only because a familiar bubble would have a physical surface, where surely, here, there is no strict interface between discrete regions of gases. But, again, the term offers an accessible image to communicate the process. (And anyone looking at the NASA image above of convection cells in the Sun might well feel that these can be perceived as if bubbles.)
(Metaphorical?) pepper
Similarly, the idea of heavy elements from exploding suns being added to the original hydrogen and helium in the interstellar medium as like adding pepper also offers a strong image,
"…this is the idea of enrichment, you start off with much more primordial hydrogen and helium gas that gets steadily peppered with all these heavy elements…"
Prof. Carolin Crawford
Perhaps 'peppered' is now a dead metaphor, as it is widely used in various contexts unrelated to flavouring food.
(Metaphorical?) imprints
When Professor Rees referred to a neutron star that has become a black hole leaving a "gravitational imprint frozen in the space that's left" this makes good sense as the black hole will not be visible, but its gravitational field will have effects well beyond its event horizon. Yet, one cannot actually make an imprint in space, one needs a suitable material substrate (snow, plater, mud…) to imprint into; and nor has anything been 'frozen' in a literal sense. Indeed, the gravitational field will change as the black hole acquires more material through gravitational capture (and in the very long term loses mass though evaporates Hawking radiation – which is said to cause the black hole to 'evaporate'). So, this is a kind of double metaphor.
(Metaphorical?) blasts and blows
I report above both the idea that rocky planet close to large stars might have derived from 'giant' planets "that have had the outer gassy layers blasted off" and how "big stars…blow off their outer layers". Can stars really blow, or is this based on a metaphor. Blasts usually imply explosions, sudden events, so perhaps these are metaphorical blasts? And it is not just larger stars that engage in blowing off,
"[The sun] will blow off its outer layers and become a red giant, expanding so it will engulf the inner planets, but then the core will settle down to what's called a white dwarf, this is a dead, dense star, about a million times denser than normal stuff…."
Prof. Martin Rees
Metaphors galore!
Perhaps those last examples are not especially convincing – but this reflects a point I made earlier. Language changes over time: it is (metaphorically-speaking) fluid. If language started from giving names to things we can directly point at, then anything we cannot directly point at needs to be labelled in terms of existing words. Most of the terms we use were metaphors at some point, but became literal as the language norms changed.
But society is not a completely homogeneous language community. The requirements of professional discourse in astronomy (or any other specialised field of human activity) drive language modifications in particular regards ahead of general language use. It is not just people in Britain and the United States who are divided by a common language – we all are to some extent. What has become literal meaning for for one person (perhaps a science teacher) may well only be a metaphor to another (a student, say).
After all, when I look up what it is to blow off, I find that the most common contemporary meaning relates to a failure to meet a social obligation or arrangement – I am pretty sure (from the context) that that is not what Professor Rees was suggesting ("…when those big stars face a crisis they [let down] their outer layers".) Once we start looking at texts closely, they seem to be 'loaded' with figures of speech. A planet is not materially constrained in space, yet we understand why an orbit might be considered 'tight'.
In the proceeding quote, the core of a star seems to need no explanation although it presumably derives by analogy with the core of an apple or similar fruit, which itself seems to derive metaphorically form an original meaning of the heart. Again, what is meant by engulf is clear enough although originally it referred to the context of water and the meaning has been metaphorically (or analogously) extended.
The terms red giant and white dwarf clearly derive from metaphor. (Sure, a red giant isgigantic, but then, on any normal scale of human experience, so is a white dwarf.) These terms might mystify someone meeting them for the first time so not already aware they are used to refer to classes of star. This might suggest the value of a completely objective language for discussing science where all terms are tightly (hm, too metaphorical…closely? rigidly? well-) defined, but that would be a project reminiscent of the logical positivist programme in early twentieth century that ultimately proved non-viable. We can only define words with more words, and there are limits to the precision possible with a usable, 'living', language.
Take the "discovery that we are literally made of the ashes of long dead stars". Perhaps, but the term ashes normally refers to the remains of burnt organic material, especially wood, so perhaps we are not literally, but only metaphorically made of the ashes of long dead stars. Just as when when Professor Sullivan noted,
"the white dwarf is made of carbon, it's made of oxygen, and the temperature and the pressure in the centre of that white dwarf star can become so extreme, that carbon detonation can occur in the centre of the white dwarf, and that is a runaway thermonuclear reaction – that carbon burns in astronomer speak into more massive elements…"
Prof. Mark Sullivan
Are we stardust, ashes or just waste?
Burning is usually seen in scientific terms as another word for combustion. So, the nuclear fusion, 'burning' "in astronomer speak" of its nuclear 'fuel' in a star represents an extension of the original meaning by analogy with combustion. 9 Material that is deliberately used to maintain a fire is fuel. A furnace is an artefact deliberately built to maintain a high temperature – the nuclear furnace in a star is not an artefact but a naturally occurring system (gravity holds the material in place), but is metaphorically a furnace. A runaway is a fugitive who has absconded – so to describe a thermonuclear reaction (which is not going anywhere in spatial terms) as 'runaway' adopts what was a metaphor. (Astronomers also use the term 'runaway' to label a class of star that seem to be moving especially fast compared with the interstellar medium – a somewhat more direct borrowing of the usual meaning of 'runaway'.)
To consider us to be made from 'nuclear waste' relies on seeing the star-as-nuclear-furnace as analogous to a nuclear pile in a power station. In nuclear power stations we deliberately process fissile material to allow us to generate electrical power: and material is produced as a by-product of this process (that is, it is a direct product of the natural nuclear processes, but a by-product of our purposeful scheme to generate electricity). To consider something waste means making a value judgement.
If the purpose of a star is to shine (a teleological claim) and the fusion of hydrogen is the means to achieve that end, then the material produced in that process which is no longer suitable as 'fuel' can be considered 'waste'. If the universe does not have any purpose(s) for stars then there is no more basis for seeing this material as waste than there is for seeing stars themselves as the waste products of a process that causes diffuse matter to come together into local clumps. That is, this is an anthropocentric perspective that values stars as of more value than either the primordial matter from which they formed, or the 'dead' matter they will evolve into when they no longer shine 'for us'. Nature may not have such favourites! If it has a purpose, then stars seem to only be intermediate steps towards its ultimate end.
What does support the turtle? Surely, it's metaphors all the way down. (Source: Pintrest)
Sources cited:
Eddington, A. (1933/1987). The Expanding Universe. Cambridge: Cambridge University Press.
Lakoff, G., & Johnson, M. (1980). The metaphorical structure of the human conceptual system. Cognitive Science, 4(2), 195-208.
Ulmer, M., Grace, V., Hudson, H., & Schwartz, D. (1972). Upper Limits to the X-Ray Luminosities of Five Supernovae. The Astrophysical Journal, 173, 205.
Notes:
1 It may seem fanciful that we give a specific individual tree a proper name but should a child inherently appreciate that we commonly name individual hamsters (say, or ships, or roads), but not individual trees? 'Major Oak'is a particular named Oak tree in Sherwood Forest, so the idea is not ridiculous. (It is very large, but apparently the name derives from it being described by an author with the army rank of major. Of course, this term for a soldier leading others derives metaphorically from a Latin word meaning bigger, so…)
2 "So how do we bridge between dogs and trees on one hand and electrons and the strong nuclear force on the other (so to speak!)? The answer is we build using analogy and we talk about those constructions using a great deal of metaphor."
We understand what is meant by bridge here in relation to an actual bridge that physically links two places – such as locations on opposite sides of a river or railway line.
There is no actual building up of materials, but we understand how we can 'build' in the abstract by analogy.
These things are not actually at hand, but we make a metaphorical comparison in terms of distinguishing items held in 'opposite' hands. We understand what is meant by a great deal of something abstract by analogy with a great deal of something we can directly experience, e.g., sand, water, etcetera.
Justice personified, on the one hand weighing up the evidence and on the other imposing sanctions
(Image by Sang Hyun Cho from Pixabay)
We construct scientific concepts and models and theories by analogy with how we construct material buildings – we put down foundations then build up brick by brick so that the top of the structure is only very indirectly supported by the ground.
(Image by joffi from Pixabay)
3 A point is a hypothetical, infinitesimally small, location in space, which is not something a person could actually make. The 'point' of an argument is metaphorically like the point of a pencil or spear which is metaphorically an approximation to an actual point. Of course, we (adult members of the English language community) all know what is meant by the point of an argument – but people new to a language (such as young children) have to find this out, without someone holding up the point of an argument for them to learn to recognise.
4 In part, this means linguistic resources. Each individual person has a unique vocabulary, and even though sharing most words with others, often has somewhat unique ranges of application of those words. But it also refers to personal experiences that can be drawn upon (e.g., having cared for an ill relative, having owned a pet, having undertaken part-time work in a hospital pharmacy, having been taken to work by a parent…) and the cultural referents that are commonly discussed in discourse (cultural icons like the Mona Lisa or Beethoven's fifth symphony; familiarity with some popular television show or film; appreciating that Romeo and Juliet were tragic lovers, or that Gandhi is widely considered a moral role model, and so forth.)
"Penny, I'm a physicist. I have a working knowledge of the entire universe and everything it contains."
"Who's Radiohead?"
"I have a working knowledge of the important things in the universe."
Still from 'The Big Bang Theory' (Chuck Lorre Productions / Warner Bros. Television)
The interpretive resources are whatever mental resources are available to help make sense of communication.
5 I am using the term concept in an 'inclusive' sense (Taber, 2019), in that whenever a person can offer a discrimination about whether something is an example of some category, then they hold a concept (vague or detailed; simple or complex; canonical or alternative).
That is, if someone can (beyond straight guesswork) try to answer one of the questions "what is X? ", "is this an example of X?" or "can you suggests an example of X?", then they have a relevant concept – where X could be…
6 The earliest reference to 'host galaxies' I found in a quick search of the scientific literature was from 1972 in a paper which used the term 'host galaxy' 8 times, including,
"We estimated the distances [of observed supernovae]…by four different methods:
(1) Estimating the absolute luminosity of the host galaxy.
(2) Estimating the absolute luminosity of the supernova.
(3) Using the measured redshift of the host galaxy and assuming the Hubble constant H = 75 km (s Mpc)-1 …
(4) Identifying the host galaxy with a cluster of galaxies for which the distance from Earth had already been estimated.
Ulmer, Grace, Hudson & Schwartz, 1972, p.209
The term 'host galaxy' was not introduced or defined in the paper, suggesting that either it was already in common use as a scientific term (and so a dead metaphor within the astronomical community) in 1972 or Ulmer and colleagues assumed it was obvious enough not to need explanation.
7 It should be pointed out that 'In Our Time' is not presented as succession of mini-lectures, or as a tightly scripted programme, but as a conversation between Melvyn as his guests. Of course, there is some level of preparation by those involved, but in adopting a conversational style, avoiding the sense of prepared statements, it is inevitable that a guest's language will sometimes lack the precision of a drafted and much revised account.
8 A supernova may appear as a new star in the sky if it is so far away that the star was not previously detectable, or as a known star quick;y becoming very much brighter.
9 One should be careful in making such equivalences, as in that although we may equate burning with combustion, burning is an everyday ('life world') phenomenon, and combustion is a scientific concept: often our scientific concepts are more precisely defined than the related everyday terms. (Which is why melting has a broader meaning in everyday life {the sugar melts in the hot tea; the stranger melted away into the mist} than it does in science.) But although we might say, as suggested earlier in the text, we have been burned by exposure to the sun's ultraviolet rays, or by contact with a caustic substance, in those contexts we are unlikely to consider our skin as 'fuel' for the process.
It seems a bloated star dimmed because it sneezed, and spewed out a burp.
'Pardon me!' (Image by Angeles Balaguer from Pixabay)
I was intrigued to notice a reference in Chemistry World to a 'stellar burp'.
"…the dimming of the red giant Betelgeuse that was observed in 2019…was later attributed to a 'stellar burp' emitting gas and dust which condensed and then obscured light from the star"
Motion, 2022
The author, Alice Motion, quoted astrophysics doctoral candidate and science communicator Kirsten Banks commenting that
"In recorded history…It's the first time we've ever seen this happen, a star going through a bit of a burp"
although she went on to suggest that the Boorong people (an indigenous culture from an area of the Australian state Victoria) had long ago noticed a phenomena that became recorded in their oral traditions 1, which
"was actually the star Eta Carinae which went through a stellar burp, just like Betelgeuse did"
Clearly a star cannot burp in the way a person can, so I took this to be a metaphor, and wondered if this was a metaphor used in the original scientific report.
A clump and a veil
The original report (Montargès, et al, 2021) was from Nature, one of the most prestigious science research journals. It did not seem to have any mention of belching. This article reported that,
"From November 2019 to March 2020, Betelgeuse – the second-closest red supergiant to Earth (roughly 220 parsecs, or 724 light years, away) – experienced a historic dimming of its visible brightness…an event referred to as Betelgeuse's Great Dimming….Observations and modelling support a scenario in which a dust clump formed recently in the vicinity of the star, owing to a local temperature decrease in a cool patch that appeared on the photosphere."
Montargès, et al., 2012, p.365
So, the focus seemed to be not on any burping but a 'clump' of material partially obscuring the star. That material may well have arisen from the star. The paper in nature suggests that Betelgeuse may loose material through two mechanisms: both by a "smooth homogeneous radial outflow that consists mainly of gas", that is a steady and continuous process; but also "an episodic localised ejection of gas clumps where conditions are favourable for efficient dust formation while still close to the photosphere" – that is the occasional, irregular, 'burp' of material, that then condenses near the star. But the word used was not 'burp', but 'eject'.
A fleeting veil
Interestingly the title of the article referred to "A dusty veil shading Betelgeuse". The 'veil' (another metaphor) only seemed to occur in the title. There is an understandable temptation, even in scholarly work, to seek a title which catches attention – perhaps simplifying, alliterating (e.g., '…mediating mental models of metals…') or seeking a strong image ('…a dusty veil shading…'). In this case, the paper authors clearly thought the metaphor did not need to be explained, and that readers would understand how it linked to the paper content without any explicit commentary.
Word
Frequency in Nature article
clump(s)
25 (excluding reference list)
eject(ed, etc.)
4
veil
1 (in title only)
burp
0
blob
0
There's no burping in Nature
The European Southern Observatory released a press release (sorry, a 'science release') about the work entitled 'Mystery of Betelgeuse's dip in brightness solved', that explained
"In their new study, published today in Nature, the team revealed that the mysterious dimming was caused by a dusty veil shading the star, which in turn was the result of a drop in temperature on Betelgeuse's stellar surface.
Betelgeuse's surface regularly changes as giant bubbles of gas move, shrink and swell within the star. The team concludes that some time before the Great Dimming, the star ejected a large gas bubble that moved away from it. When a patch of the surface cooled down shortly after, that temperature decrease was enough for the gas to condense into solid dust.
'We have directly witnessed the formation of so-called stardust,' says Montargès, whose study provides evidence that dust formation can occur very quickly and close to a star's surface. 'The dust expelled from cool evolved stars, such as the ejection we've just witnessed, could go on to become the building blocks of terrestrial planets and life', adds Emily Cannon, from KU Leuven, who was also involved in the study."
So, again, references to ejection and a veil – but no burping.
Delayed burping
Despite this, the terminology of the star burping, seems to have been widely taken up in secondary sources, such as the article in Chemistry World
A New Scientist report suggested "Giant gas burp made Betelgeuse go dim" (Crane, 2021). On the website arsTECHNICA, Jennifer Ouellette wrote that "a cold spot and a stellar burp led to strange dimming of Betelgeuse".
On the newsite Gizmodo, George Dvorsky wrote a piece entitled "A dusty burp could explain mysterious dimming of supergiant star Betelgeuse". Whilst the term burp was only used in the title, Dvorsky was not shy of making other corporeal references,
"a gigantic dust cloud, which formed after hot, dense gases spewed out from the dying star. Viewed from Earth, this blanket of dust shielded the star's surface, making it appear dimmer from our perspective, according to the research, led by Andrea Dupree from the Centre for Astrophysics at Harvard & Smithsonian.
A red supergiant star, Betelgeuse is nearing the end of its life. It's poised to go supernova soon, by cosmological standards, though we can't be certain as to exactly when. So bloated is this ageing star that its diameter now measures 1.234 million kilometers, which means that if you placed Betelgeuse at the centre of our solar system, it would extend all the way to Jupiter's orbit."
The New York Times published an article (June 17, 2021) entitled "Betelgeuse Merely Burped, Astronomers Conclude", where author Dennis Overbye began his piece:
Overbye also reports the work from the Nature paper
"We have directly witnessed the formation of so-called stardust," Miguel Montargès, an astrophysicist at the Paris Observatory, said in a statement issued by the European Southern Observatory. He and Emily Cannon of Catholic University Leuven, in Belgium, were the leaders of an international team that studied Betelgeuse during the Great Dimming with the European Southern Observatory's Very Large Telescope on Cerro Paranal, in Chile.
Parts of the star, they found, were only one-tenth as bright as normal and markedly cooler than the rest of the surface, enabling the expelled blob to cool and condense into stardust. They reported their results on Wednesday in Nature."
So, instead of the clumps referred to in the Nature article as ejected, we now have an expelled blob (neither word appears in the nature article itself). Overbye also explains how this study followed up on earlier observations of the star
"Their new results would seem to bolster findings reported a year ago by Andrea Dupree of the Harvard-Smithsonian Center for Astrophysics and her colleagues, who detected an upwelling of material on Betelgeuse in the summer of 2019.
'We saw the material moving out through the chromosphere in the south in September to November 2019,', Dr. Dupree wrote in an email. She referred to the expulsion as 'a sneeze.'
'…material moving out through the chromosphere in the south…': Hubble space telescope images of Betelgeuse (Source: NASA) 2
Bodily functions and stellar processes
I remain unsure why, if the event was originally considered a sneeze, it became transformed into a burp. However the use of such descriptions is not so unusual. Metaphor is a common tool in science communication to help 'make the unfamiliar familiar' by describing something abstract or out-of-the-ordinary in more familiar terms.
Here, the body [sic] of the scientific report keeps to technical language although a metaphor (the dust cloud as a veil) is considered suitable for the title. It is only when the science communication shifts from the primary literature (intended for the science community) into more popular media aimed at a wider audience that the physical processes occurring in a star became described in terms of our bodily functions. So, in this case, it seems a bloated star dimmed because it sneezed, and spewed out a burp.
Coda
The astute reader may have also noticed that the New York Times article referred to Betelgeuse as an "ageing star" that is "nearing the end of its life": terms that imply a star is a living, and mortal, being. This might seem to be journalistic license, but the NASA website from which the sequence of Betelgeuse images above are taken also refers to the star as ageing (as well as being 'petulant' and 'injured').2 NASA employs scientifically qualified people, but its public websites are intended for a broad, general audience, perhaps explaining the anthropomorphic references.
Crane, L. (2021). Giant gas burp made Betelgeuse go dim. New Scientist, 250(3340), 22. doi:10.1016/S0262-4079(21)01094-0
Hamacher, D. W., & Frew, D. J. (2010). An aboriginal Australian record of the great eruption of Eta Carinae. Journal of Astronomical History and Heritage, 13(3), 220-234.
Montargès, M., Cannon, E., Lagadec, E., de Koter, A., Kervella, P., Sanchez-Bermudez, J., . . . Danchi, W. (2021). A dusty veil shading Betelgeuse during its Great Dimming. Nature, 594(7863), 365-368. doi:10.1038/s41586-021-03546-8
1 William Edward Stanbridge (1816-1894) was an Englishman who moved to Australia in 1841. He asked Boorong informants about their astronomy, and recorded their accounts. He presented a report to the Philosophical Institute of Victoria in 1857 and published two papers (Hamacher & Frew, 2010). The website Australian Indigenous Astronomy explains that
"The larger star of [of the binary system] Eta Car is unstable and undergoes occasional violent outbursts, where it sheds material from its outer shells, making it exceptionally bright. During the 1840s, Eta Car went through such an outburst where it shed 20 solar masses of its outer shell and became the second brightest star in the night sky, after Sirius, before fading from view a few years later. This event, commonly called a "supernova-impostor" event, has been deemed the "Great Eruption of Eta Carinae". The remnant of this explosion is evident by the Homunculus Nebulae [see figure above – nebulae are anything that appears cloud-like to astronomical observation]. This identification shows that the Boorong had noted the sudden brightness of this star and incorporated it into their oral traditions."
A paper in the Journal of Astronomical History and Heritage concludes that
"the Boorong people observed 𝜂 Carinae in the nineteenth century, which we identify using Stanbridge's description of its position in Robur Carolinum, its colour and brightness, its designation (966 Lac, implying it is associated with the Carina Nebula), and the relationship between stellar brightness and positions of characters in Boorong oral traditions. In other words, the nineteenth century outburst of 𝜂 Carinae was recognised by the Boorong and incorporated into their oral traditions"
Hamacher & Frew 2010, p.231
2 The images reproduced here are presented on a NASA website under the heading 'Hubble Sees Red Supergiant Star Betelgeuse Slowly Recovering After Blowing Its Top'. This is apparently not a metaphor as the site informs readers that"Betelgeuse quite literally blew its top in 2019". Betelgeuse is described as a "monster star", and its activity as "surprisingly petulant behaviour" and a "titanic convulsion in an ageingstar", such that "Betelgeuse is now struggling to recover from this injury."
This seems rather anthropomorphic – petulance and struggle are surely concepts that refer to sentient deliberate actors in the world, not massive hot balls of gas. However, anthropomorphic narratives are often used to make scientific ideas accessible.
The recovery (from 'injury') is described in terms of two similes,
"The star's interior convection cells, which drive the regular pulsation may be sloshing around like an imbalanced washing machine tub, Dupree suggests. … spectra imply that the outer layers may be back to normal, but the surface is still bouncing like a plate of gelatin dessert [jelly] as the photosphere rebuilds itself."
What can either wander door to door, or rush to respond; and when it arrives might touch, sniff, nip, rear up, stroke, seal, or kill?
Keith S. Taber
a science teacher would need to be more circumspect in throwing some of these metaphors out there, without then doing some work to transition from them to more technical, literal, and canonical accounts
BBC Radio 4's 'Start the week' programme is not a science programme, but tends to invite in guests (often authors of some kind) each week according to some common theme. This week there was a science theme and the episode was titled 'Building the Body, Opening the Heart', and was fascinating. It also offers something of a case study in how science gets communicated in the media.
Sian Harding is Professor of Cardiac Pharmacology at the National Heart and Lung Institute, Imperial College London, and Director of the Imperial Cardiac Regenerative Medicine Centre
As a science educator I listen to science programmes both to enhance and update my own science knowledge and understanding, but also to hear how experts present scientific ideas when communicating to a general audience. Although neither science popularisation nor the work of scientists in communicating to the public is entirely the same as formal teaching (for example,
there is no curriculum with specified target knowledge; and
the audiences
are not well-defined,
are usually much more diverse than found in classrooms, and
are free to leave at any point they lose interest or get a better offer),
they are, like teachers, seeking to inform and explain science.
Science communicators, whether professional journalists or scientists popularising their work, face similar challenges to science teachers in getting across often complex and abstract ideas; and, like them, need to make the unfamiliar familiar. Science teachers are taught about how they need to connect new material with the learners' prior knowledge and experiences if it is to make sense to the students. But successful broadcasters and popularisers also know they need to do this, using such tactics as simplification, modelling, metaphor and simile, analogy, teleology, anthropomorphism and narrative.
Perhaps one of the the biggest differences between science teaching and science communication in the media is the ultimate criterion of success. For science teachers this is (sadly) usually, primarily at least, whether students have understood the material, and will later recall it, sufficiently to demonstrate target knowledge in exams. The teacher may prefer to focus on whether students enjoy science, or develop good attitudes to science, or will consider working in science: but, even so, they are usually held to account for students' performance levels in high-stakes tests.
Science journalists and popularisers do not need to worry about that. Rather, they have to be sufficiently engaging for the audience to feel they are learning something of interest and understanding it. Of course, teachers certainly need to be engaging as well, but they cannot compromise what is taught, and how it is understood, in order to entertain.
With that in mind, I was fascinated at the range of ways the panel of guests communicated the science in this radio show. Much of the programme had a focus on cells – and these were described in a variety of ways.
Talking about cells
Dr Rutherford introduced cells as
"the basic building blocks of life on earth"; and observed that he had
"spent much of my life staring down microscopes at these funny, sort of mundane, unremarkable, gloopy balloons"; before suggesting that cells were
"actually really these incredible cities buzzing with activity".
Dr. Mukherjee noted that
"they're fantastical living machines" [where a cell is the] "smallest unit of life…and these units were built, as it were, part upon part like you would build a Lego kit"
Listeners were told how Robert Hooke named 'cells' after observing cork under the microscope because the material looked like a series of small rooms (like the cells where monks slept in monasteries). Hooke (1665) reported,
"I took a good clear piece of Cork, and with a Pen-knife sharpen'd as keen as a Razor, I cut a piece of it off, and…cut off from the former smooth surface an exceeding thin piece of it, and…I could exceeding plainly perceive it to be all perforated and porous, much like a Honey-comb, but that the pores of it were not regular; yet it was not unlike a Honey-comb in these particulars
…these pores, or cells, were not very deep, but consisted of a great many little Boxes, separated out of one continued long pore, by certain Diaphragms, as is visible by the Figure B, which represents a sight of those pores split the long-ways.
Robert Hooke
Hooke's drawing of the 'pores' or 'cells' in cork
Components of cells
Dr. Mukherjee described how
"In my book I sort of board the cell as though it's a spacecraft, you will see that it's in fact organised into rooms and there are byways and channels and of course all of these organelles which allow it to work."
We were told that "the cell has its own skeleton", and that the organelles included the mitochondria and nuclei ,
"[mitochondria] are the energy producing organelles, they make energy in most cells, our cells for instance, in human cells. In human cells there's a nucleus, which stores DNA, which is where all the genetic information is stored."
A cell that secretes antibodies which are like harpoons or missiles that it sends out to kill a pathogen?
(Images by by envandrare and OpenClipart-Vectors from Pixabay)
Immune cells
Rutherford moved the conversation onto the immune system, prompting 'Sid' that "There's a lovely phrase you use to describe T cells, which is door to door wanderers that can detect even the whiff of an invader". Dr. Mukherjee distinguished between the cells of the innate immune system,
"Those are usually the first responder cells. In humans they would be macrophages, and neutrophils and monocytes among them. These cells usually rush to the site of an injury, or an infection, and they try to kill the pathogen, or seal up the pathogen…"
and the cells of the adaptive system, such as B cells and T cells,
"The B cell is a cell that eventually becomes a plasma cell which secretes antibodies. Antibodies, they are like harpoons or missiles which the cell sends out to kill a pathogen…
[A T cell] goes around sniffing other cells, basically touching them and trying to find out whether they have been altered in some way, particularly if they are carrying inside them a virus or any other kind of pathogen, and if it finds this pathogen or a virus in your body, it is going to go and kill that virus or pathogen"
A cell that goes around sniffing other cells, touching them? 1 (Images by allinonemovie and OpenClipart-Vectors from Pixabay)
Cells of the heart
Another topic was the work of Professor Harding on the heart. She informed listeners that heart cells did not get replaced very quickly, so that typically when a person dies half of their heart cells had been there since birth! (That was something I had not realised. It is believed that this is related to how heart cells need to pulse in synchrony so that the whole organ functions as an effective pumping device – making long lasting cells that seldom need replacing more important than in many other tissues.)
At least, this relates to the cardiomyocytes – the cells that pulse when the heart beats (a pulse that can now be observed in single cells in vitro). Professor Harding described how in the heart tissue there are also other 'supporting' cells, such as "resident macrophages" (immune cells) as well as other cells moving around the cardiomyocytes. She describe her observations of the cells in Petri dishes,
"When you look at them in the dish it's incredible to see them interact. I've got a… video [of] cardiomyocytes in a dish. The cardiomyocytes pretty much just stay there and beat and don't do anything very much, and I had this on time lapse, and you could see cells moving around them. And so, in one case, the cell (I think it was a fibroblast, it looked like a fibroblast), it came and it palpated at the cardiomyocyte, and it nipped off bits of it, it sampled bits of the cardiomyocyte, and it just stroked it all the way round, and then it was, it seemed to like it a lot.
[In] another dish I had the same sort of cardiomyocyte, a very similar cell came in, it went up to the cardiomyocyte, it touched it, and as soon as it touched it, I can only describe it as it reared up and it had, little blobs appeared all over its surface, and it rushed off, literally rushed off, although it was time lapse so it was two minutes over 24 hours, so, it literally rushed off, so what had it found, why did one like it and the other one didn't?"
Making the unfamiliar, familiar
The snippets from the broadcast that I have reported above demonstrate a wide range of ways that the unfamiliar is made familiar by describing it in terms that a listener can relate to through their existing prior knowledge and experience. In these various examples the listener is left to carry across from the analogue features of the familiar (the city, the Lego bricks, human interactions, etc.) those that parallel features of the target concept – the cell. So, for example, the listener is assumed to appreciate that cells, unlike Lego bricks, are not built up through rigid, raised lumps that fit precisely in depressions on the next brick/cell. 2
Analogies with the familiar
Hooke's original label of the cell was based on a kind of analogy – an attempt to compare what we has seeing with something familiar: "pores, or cells…a great many little Boxes". He used the familiar simile of the honeycomb (something directly familiar to many more people in the seventeenth century when food was not subject to large-scale industrialised processing and packaging).
Other analogies, metaphors and similes abound. Cells are visually like "gloopy balloons", but functionally are "building blocks" (strictly a metaphor, albeit one that is used so often it has become treated as though a literal description) which can be conceptualised as being put together "like you would build a Lego kit" (a simile) although they are neither fixed, discrete blocks of a single material, nor organised by some external builder. They can be considered conceptually as the"smallest unit of life"(though philosophers argue about such descriptions and what counts as an individual in living systems).
The machine description ("fantastical living machines") reflects one metaphor very common in early modern science and cells as "incredible cities" is also a metaphor. Whether cells are literally machines is a matter of how we extend or limit our definition of machines: cells are certainly not actually cities, however, and calling them such is a way of drawing attention to the level of activity within each (often, apparently from observation, quite static) cell. B cells secrete antibodies, which the listener is old are like (a simile) harpoons or missiles – weapons.
Skeletons of the dead
Whether "the cell has its own skeleton" is a literal or metaphorical statement is arguable. It surely would have originally been a metaphoric description – there are structures in the cell which can be considered analogous to the skeleton of an organism. If such a metaphor is used widely enough, in time the term's scope expands to include its new use – and it becomes (what is called, metaphorically) a 'dead metaphor'.
Telling stories about cells
A narrative is used to help a listener imagine the cell at the scale of "a spacecraft". This is "organised into rooms and there are byways and channels" offering an analogy for the complex internal structure of a cell. Most people have never actually boarded a spacecraft, but they are ubiquitous in television and movie fiction, so a listener can certainly imagine what this might be like.
Endoplastic reticulum? (Still from Star Trek: The Motion Picture, Paramount Pictures, 1979)
Oversimplification?
The discussion of organelles illustrates how simplifications have to be made when introducing complex material. This always brings with it dangers of oversimplification that may impede further learning, or even encourage the development of alternative conceptions. So, the nucleus does not, strictly, 'store' "all the genetic information" in a cell (mitochondria carry their own genes for example).
More seriously, perhaps, mitochondria do not "make energy". 'More seriously' as the principle of conservation of energy is one of the most basic tenets of modern science and is considered a very strong candidate for a universal law. Children are often taught in school that energy cannot be created or destroyed. Science communication which is contrary to this basic curriculum science could confuse learners – or indeed members of the public seeking to understand debates about energy policy and sustainability.
Anthropomorphising cells
Cells are not only compared to inanimate entities like balloons, building bricks, cities and spaceships. They are also described in ways that make them seem like sentient agents – agents that have experiences, and conscious intentions, just as people do. So, some immune cells are metaphorical 'first responders' and just as emergency services workers they "rush to the site" of an incident. To rush is not just to move quickly, buy to deliberately do so. (By contrast, Paul McAuley refers to "innocent" amoeboid cells that collectively form into the plasmodium of a slime mould spending most of their lives"bumbling around by themselves" before they "get together". ) The immune cells act deliberately – they "try" to kill. Other immune cells "send out" metaphorical 'missiles' "to kill a pathogen". Again this language suggests deliberate action (i.e., to send out) and purpose.
That is, what is described is not just some evolved process, but something teleological: there is a purpose to sending out antibodies – it is a deliberate act with an aim in mind. This type of language is very common in biology – even referring to the 'function' of the heart or kidney or a reflex arc could be considered as misinterpreting the outcome of evolutionary developments. (The heart pumps blood through the vascular system, but referring to a function could suggest some sense of deliberate design.)
Not all cells are equal
I wonder how many readers noticed the reference above to 'supporting' cells in the heart. Professor Harding had said
"When you look inside the [heart] tissue there are many other cells [than cardiomyocytes] that are in there, supporting it, there are resident macrophages, I think we still don't know really what they are doing in there"
Why should some heart cells be seen as more important and others less so? Presumably because 'the function' of a heart is to beat, to pump, so clearly the cells that pulse are the stars, and the other cells that may be necessary but are not obviously pulsing just a supporting cast. (So, cardiomyocytes are considered heart cells, but macrophages in the same tissue are only cells that are found in the heart, "residents" – to use an analogy of my own, like migrants that have not been offered citizenship!)3
That is, there is a danger here that this way of thinking could bias research foci leading researchers to ignore something that may ultimately prove important. This is not fanciful, as it has happened before, in the case of the brain:
"Glial cells, consisting of microglia, astrocytes, and oligodendrocyte lineage cells as their major components, constitute a large fraction of the mammalian brain. Originally considered as purely non-functional glue for neurons, decades of research have highlighted the importance as well as further functions of glial cells."
Jäkel and Dimou, 2017
The lives of cells
Narrative is used again in relation to the immune cells: an infection is presented as a kind of emergency event which is addressed by special (human like) workers who protect the body by repelling or neutralising invaders. "Sniffing" is surely an anthropomorphic metaphor, as cells do not actually sniff (they may detect diffusing substances, but do not actively inhale them). Even "touching" is surely an anthropomorphism. When we say two objects are 'touching' we mean they are in contact, as we touch things by contact. But touching is sensing, not simply adjacency.
If that seems to be stretching my argument too far, to refer to immune cells "trying to find out…" is to use language suggesting an epistemic agent that can not only behave deliberately, but which is able to acquire knowledge. A cell can only "find" an infectious agent if it is (i.e., deliberately) looking for something. These metaphors are very effective in building up a narrative for the listener. Such a narrative adopts familiar 'schemata', recognisable patterns – the listener is aware of emergency workers speeding to the scene of an incident and trying to put out a fire or seeking to diagnose a medical issue. By fitting new information into a pattern that is familiar to the audience, technical and abstract ideas are not only made easier to understand, but more likely to be recalled later.
Again, an anthropomorphic narrative is used to describe interactions between heart cells. So, a fibroblast that "palpates at" a cardiomyocyte seems to be displaying deliberate behaviour: if "nipping" might be heard as some kind of automatic action – "sampling" and "stroking" surely seem to be deliberate behaviour. A cell that "came in, it went up [to another]" seems to be acting deliberately. "Rearing up" certainly brings to mind a sentient being, like a dog or a horse. Did the cell actually 'rear up'? It clearly gave that impression to Professor Harding – that was the best way, indeed the "only" way, she had to communicate what she saw.
Again we have cells "rushing" around. Or do we? The cell that had reared up, "rushed off". Actually, it appeared to "rush" when the highly magnified footage was played at 720 times the speed of the actual events. Despite acknowledging this extreme acceleration of the activity, the impression was so strong that Professor Harding felt justified in claiming the cell "literally rushed off, although it was time lapse so it was two minutes over 24 hours, so, it literally rushed off…". Whatever it did, that looked like rushing with the distortion of time-lapse viewing, it certainly did not literally rush anywhere.
But the narrative helps motivate a very interesting question, which is why the two superficially similar cells 'behaved' ('reacted', 'responded' – it is actually difficult to find completely neutral language) so differently when in contact with a cardiomyocyte. In more anthropomorphic terms: what had these cells "found, why did one like it and the other one didn't?"
Literally speaking?
Metaphorical language is ubiquitous as we have to build all our abstract ideas (and science has plenty of those) in terms of what we can experience and make sense of. This is an iterative process. We start with what is immediately available in experience, extend metaphorically to form new concepts, and in time, once those have "settled in" and "taken root" and "firmed up" (so to speak!) they can then be themselves borrowed as the foundation for new concepts. This is true both in how the individual learns (according to constructivism) and how humanity has developed culture and extended language.
So, should science communicators (whether scientists themselves, journalists or teachers) try to limit themselves to literal language?
Even if this were possible, it would put aside some of our strongest tools for 'making the unfamiliar familiar' (to broadcast audiences, to the public, to learners in formal education). However these devices also bring risks that the initial presentations (with their simplifications and metaphors and analogies and anthropomorphic narratives…) not only engage listeners but can also come to be understood as the scientific account. That is is not an imagined risk is shown by the vast numbers of learners who think atoms want to fill their shells with octets of electrons, and so act accordingly – and think this because they believe it is what they have been taught.
Does it matter if listeners think the simplification, the analogy, the metaphor, the humanising story,… is the scientific account? Perhaps usually not in the case of the audience listening to a radio show or watching a documentary out of interest.
In education it does matter, as often learners are often expected to progress beyond these introductory accounts in their thinking, and teachers' models and metaphors and stories are only meant as a starting point in building up a formal understanding. The teacher has to first establish some kind of anchor point in the students' existing understandings and experiences, but then mould this towards the target knowledge set out in the curriculum (which is often a simplified account of canonical knowledge) before the metaphor or image or story becomes firmed-up in the learners' minds as 'the' scientific account.
'Building the Body, Opening the Heart' was a good listen, and a very informative and entertaining episode that covered a lot of ideas. It certainly included some good comparisons that science teachers might borrow. But I think in a formal educational context a science teacher would need to be more circumspect in throwing some of these metaphors out there, without then doing some work to transition from them to more technical, literal, and canonical accounts.
Jäkel S and Dimou L (2017) Glial Cells and Their Function in the Adult Brain: A Journey through the History of Their Ablation. Frontiers in Cellullar Neuroscience, 11:24. doi: 10.3389/fncel.2017.00024
1 The right hand image portrays a mine, a weapon that is used at sea to damage and destroy (surface or submarine) boats. The mine is also triggered by contact ('touch').
2 That is, in an analogy there are positive and negative aspects: there are ways in which the analogue IS like the target, and ways in which the analogue is NOT like the target. Using an analogy in communication relies on the right features being mapped from the familiar analogue to the unfamiliar target being introduced. In teaching it is important to be explicit about this, or inappropriate transfers may be made: e.g., the atom is a tiny solar system so it is held together by gravity (Taber, 2013).
3 It may be a pure coincidence in relation to the choice of term 'resident' here, but in medicine 'residents' have not yet fully qualified as specialist physicians or surgeons, and so are on placement and/or under supervision, rather than having permanent status in a hospital faculty.
"From one of the known ingredients of steam being a highly inflammable body, and the other that essential part of the air which supports combustion, it was imagined that [steam] would have the effect of increasing the fire …"
Producing iron requires high temperatures: adding H2O does not help (Image by zephylwer0 from Pixabay)
The challenge of chemical combination
School science teachers are likely aware of how chemistry poses some significant leaning challenges for learners. One of these is the nature of chemical compounds. That is, compounds of chemical elements.
It may seem obvious to learners that when we 'mix' two components with different properties we should get a mixture with a combination of the component properties. So far, so good. But of course, in chemical reactions we do not just mix different substances, but rather they chemically react. So, sodium will react with chlorine, which can be understood in terms of processes occurring at the nanoscopic scale where molecules of a gas interact with the metallic lattice of sodium cations and delocalised electrons.
Sodium and chlorine behaving badly
Although we can model this process, we cannot observe it directly, or even the starting structures at that scale. Understandably, students often struggle to relate the macroscopic and molecular:
As Sodium is a reactive meterial [sic] and chlorine is a acid. When Sodium is placed in Chlorine, Sodium react badly making a flame and maybe a noise. I think why this reaction happen is because as Sodium reactive metal meaning that it atomic configuration is unstable make the metal danger And as Chlorine is a dangerous acid. When sodium is placed in Chlorine, the sodium start dissolving in the acid due to all the particle rushing around quickly pushing together with Chlorine atom. Producing Sodium chloride.
Student setting out on Advanced level chemistry, quoted in Taber, 1996
So, for example, if we do burn sodium in chlorine we end up with sodium chloride which is a new substance that has its own properties – properties which are not simply some mixture of, or intermediate between, the properties of the substances we start with (the reactants).
Indeed, sodium is a dangerous material to handle: it will react vigorously with water (in a person's sweat for example!) and burns violently in air. Chlorine is so nasty that it has been used as a weapon of war (and since banned as an 'unacceptable' weapon, even in war). In the 'great' war ('great' only because of its scale) the way men died in agony from breathing chlorine was much reported, as well as the effects on those who survived the gas – being blinded for example.
"In all my dreams before my helpless sight,
He plunges at me, guttering, choking, drowning."
Wilfred Owen, Dulce et Decorum Est1
Sweet and honourable? 1 (Image by Bruce Mewett from Pixabay)
Sodium chloride certainly has its associated hazards – if eaten in excess it is a risk factor for high blood pressure for example – but is certainly not dangerous in anything like the same sense. Many people put sodium chloride on their chips (often along with ethanoic acid solution). No one would want sodium on their food, or to eat in a canteen with a chlorine atmosphere!
When is something both present and not present?
Why this is especially challenging is that the chemistry teacher tells the students that although, at one level, the new substance does not contain its precursors – there is no sodium (substance) or chlorine (substance) in the substance sodium chloride – yet it is a compound of these elements and in some some sense the elements remain 'in' the compound.
Learning chemistry requires understanding how disciplinary concepts explained in terms of submicroscopic level models (After Figure 5, Taber, 2013)
This links to that key theoretical framework in chemistry where we can explain macroscopic (bench scale) phenomena in terms of models of matter at the submicroscopic (indeed nanoscopic or even subnanoscopic) scale. The sense in which sodium chloride 'contains' sodium and chlorine is that it is comprised of a lattice of sodium ions and chloride ions – species which include the specific types of nuclei (those of charge +11 and +17 respectively) that define those elements.
So, when we ask whether the elements are in some sense 'in' the compound we have to think in terms of these abstract models at a tiny scale – there is no sodium substance or chlorine substance present, but there is something that is inherently identified with these two elements. In a sense, but a very abstract sense, the elements are still present. Or, perhaps, better, something intrinsic to those elements is still present.
"We are working here with two complementary meanings for the idea of element, one at the (macroscopic) level of phenomena we can demonstrate to students (substances, and their reactions); the other deriving from a theoretical model in terms of conjectured submicroscopic entities ('quanticles'…).
However, there is also a sense in which an element is considered to be present, in a virtual or potential sense, within its compounds. This use is more common among French-speaking chemists, and in the English-speaking world we normally consider it quite inappropriate to suggest that sodium is somehow present in sodium chloride, or hydrogen in water. Yet, of course, chemical formulae (NaCl, H2O, etc) tell us that the compounds somehow 'contain' the elements."
This is easy to understand for someone very familiar with molecular level models – but is understandably difficult for novice learners. Thus we can reasonably understand why there are common alternative conceptions along the lines of students thinking that, for example, a compound of a dangerous element (say chlorine) must also be dangerous. Yet we 'mix' and react a soft, reactive, metal and a choking green gas – and get hard white crystals that safely dissolve in water to give a solution we can use in cooking, or to soak our feet, or to gargle with.
An historical precedent
Because science teachers and chemists are so used to thinking in models at the molecular level, we can forget just how unfamiliar this perspective is to the novice, and so the challenge of acquiring the scientific ways of thinking that have become 'second nature' through extensive application.
I was therefore fascinated to see an example of this same alternative conception, assuming a compound will show the properties of its constituent elements, reported by the scientist Sir John Herschel (astronomer, chemist, mathematician, philosopher…), not in a school science context, but rather an industrial context.
"The smelting of iron requires the application of the most violent heat that can be raised, and is commonly performed in tall furnaces, urged by great iron bellows driven by steam-engines. Instead of employing this power to force air into the furnace through the intervention of bellows, it was, on one occasion, attempted to employ the steam itself in, apparently, a much less circuitous manner; viz. by directing the current of steam in a violent blast, from the boiler at once into the fire. From one of the known ingredients of steam being a highly inflammable body, and the other that essential part of the air which supports combustion, it was imagined that this would have the effect of increasing the fire to tenfold fury, whereas it simply blew it out; a result which a slight consideration of the laws of chemical combination, and the state in which the ingredient elements exist in steam, would have enabled any one to predict without a trial."
Herschel, J. F. W. (1830/1851/2017), §37 2
So, here, instead of dropping marks on a test, this misunderstanding of the chemistry leads to a well-intentioned industrialist trying to generate heat in a blast furnace by adding water to the fire. But this does remind us just how counter-intuitive some of the things taught in science are. It might also be a useful anecdote to share with students to help them appreciate that that their errors are by no means unusual, or necessarily a reflection on their ability.
Perhaps this might even be a useful teaching example that could be built up into a historical anecdote which students might readily recall and that will help them remember that compounds have new properties that may be quite different from their constituent elements. So, while a mixture of the flammable gas hydrogen and oxygen can be explosive, a combination (that is, a chemical combination – a compound), of hydrogen and oxygen will not 'feed' a fire but dampen it down. Just as well, really, as otherwise emergency fire and rescue services would need to find an alternative to the widely available, inexpensive, recyclable, non-toxic, agent they widely use in fighting fires.
Compounds and mixtures are not interchangeable (Image by David Mark from Pixabay)
Work cited:
Herschel, J. F. W. (1830/1851/2017). Preliminary Discourse on the Study of Natural Philosophy. Project Gutenberg EBook.
1 Wilfred Owen was famous for his war poetry written about the horrors of the trench fighting in the 'first world war'. Owen was killed a week before the war ended. 'Dulce Et Decorum Est' referred to a Latin phrase or motto (dulce et decorum est pro patria mori) that Owen labelled as 'the old lie', that it was sweet and honourable to die in the service of one's country.
2 For some reason, "…it was imagined that this would have the effect of increasing the fire to tenfold fury, whereas it simply blew it out…" puts me in mind of
"the mighty ships tore across the empty wastes of space and finally dived screaming on to…Earth – where due to a terrible miscalculation of scale the entire battle fleet was accidentally swallowed by a small dog."
Douglas Adams, The Hitchhiker's Guide to the Galaxy
The BBC radio programme 'In Our Time' today tackled the electron. As part of the exploration there was the introduction of the positron, and the notion of matter-antimatter annihilation. These are quite brave topics to introduce in a programme with a diverse general audience (last week Melvyn Bragg and his guests discussed Plato's Atlantis and next week the programme theme is the Knights Templar).
Prof. Victoria Martin of the School of Physics and Astronomy at the University of Edinburgh explained:
If we take a pair of matter and antimatter, so, since we are talking about the electron today, if we take an electron and the positron, and you put them together, they would annihilate.
And they would annihilate not into nothingness, because they both had mass, so they both had energy from E=mc2 that tells us if you have mass you have energy. So, they would annihilate into energy, but it would not just be any kind of energy: the particular kind of energy you get when you annihilate an electron and a positron is a photon, a particle of light. And it will have a very specific amount of energy. Its energy will be equal to the sum of the energy of electron and the positron that they had initially when they collided together.
Prof. Victoria Martin on 'In Our Time'
"An electron and the positron, and you put them together, they would annihilate…they would annihilate into energy" – but this could be misleading.
Now, I am sure that is somewhat different from how Prof. Martin would treat this topic with university physics students – of course, science in the media has to be pitched at the largely non-specialist audience.
It struck me that this presentation had the potential to reinforce a common alternative conception ('misconception') that mass is converted into energy in certain processes. Although I am aware now that this is an alternative conception, I seem to recall that is pretty much what I had once understood from things I had read and heard.
It was only when I came to prepare to teach the topic that I realised that I had a misunderstanding. That, I think, is quite common for teachers – when we have to prepare a topic well enough to explain it to others, we may spot flaws in our own understanding (Taber, 2009)
So, for example, I had thought that in nuclear processes, such as in a fission reactor or fusion in stars, the mass defect (the apparent loss of mass as the resulting nuclear fragments have less mass than those present before the process) was due to that amount of massbeing converted to energy. This is sometimes said to explain why nuclear explosions are so much more violent than chemical explosions, as (given E=mc2): a tiny amount of mass can be changed into a great deal of energy.
Prof. Martin's explanation seemed to support this way of thinking: "they would annihilate into energy".
An alternative conception of particle annihilation: This scheme seems to be implied by Prof. Martin's comments
What is conserved?
It is sometimes suggested that, classically, mass and energy were considered to be separately conserved in processes, but since Einstein's theories of relativity have been adopted, now it is considered that mass can be considered as if a form of energy such that what is conserved is a kind of hybrid conglomerate. That is, energy is still considered conserved, but only when we account for mass that may have been inter-converted with energy. (Please note, this is not quite right – see below.)
So, according to this (mis)conception: in the case of an electron-positron annihilation, the mass of the two particles is converted to an equivalent energy – the mass of the electron and the mass of the positron disappear from the universe and an equivalent quantity of energy is created. Although energy is created, energy is still conserved if we allow for the mass that was converted into this new energy. Each time an electron and positron annihilate, their masses of about 2 ✕ 10-30 kg disappear from the universe and in its place something like 2 ✕ 10-13 J appears instead – but that's okay as we can consider 2 ✕ 10-30 kg as a potential form of energy worth 2 ✕ 10-13 J.
However, this is contrary to what Einstein (1917/2004) actually suggested.
Einstein did not suggest that matter could be changed to energy
Equivalence, not interconversion
What Einstein actually suggested was not that mass could be considered as if another kind/form of energy (alongside kinetic energy and gravitational potential, etc.) that needed to be taken into account in considering energy conservation, but rather that inertial mass can be considered as an (independent) measure of energy.
That is, we think energy is always conserved. And we think thatmass is always conserved. And in a sense they are two measures of the same thing. We might see these two statements as having redundancy:
In a isolated system we will always have the same total quantity of energy before and after any process.
In a isolated system we will always have the same total quantity of mass before and after any process.
As mass is always associated with energy, and so vice versa, either of these statements implies the other. 1
Two conceptions of the shift from a Newtonian to a relativistic view of the conservation of energy (move the slider to change the image)
No interconversion?
So, mass cannot be changed into energy, nor vice versa. The sense in which we can 'interconvert' is that we can always calculate the energy equivalence of a certain mass (E=mc2) or mass equivalence of some quantity of energy (m=E/c2).
So, the 'interconversion' is more like a change of units than a change of entity.
Although we might think of kinetic energy being converted to potential energy reflects a natural process (something changes), we know that changing joules to electron-volts is merely use of a different unit (nothing changes).
If we think of a simple pendulum under ideal conditions 2 it could oscillate for ever, with the total energy unchanged, but with the kinetic energy being converted to potential energy – which is then converted back to kinetic energy – and so on, ad infinitum. The total energy would be fixed although the amount of kinetic energy and the amount of potential energy would be constantly changing. We could calculate the energy in joules or some other unit such as eV or ergs (or calories or kWh or…). We could convert from one unit to another, but this would not change anything about the physical system. (So, this is less like converting pounds to dollars, and more like converting an amount reported in pounds {e.g., £24.83} into an amount reported in pence {e.g., 2483p}.)
Using this analogy, the electron and positron being converted to a photon is somewhat like kinetic energy changing to potential energy in a swinging pendulum (something changes), but it is not the case that mass is changed into energy. Rather we can do our calculations in terms of energy or mass and will get (effectively, given E=mc2) the same answer (just as we can add up a shopping list in pounds or pence, and get the same outcome given the conversion factor, 1.00£ = 100p).
So, where does the mass go?
If mass is conserved, then where does the mass defect – the amount by which the sum of masses of daughter particles is less than the mass of the parent particle(s) – in nuclear processes go? And, more pertinent to the present example, what happens to the mass of the electron and positron when they mutually annihilate?
To understand this, it might help to bear in mind that in principle these process are like any other natural processes – such as the swinging pendulum, or a weight being lifted with pulley, or methane being combusted in a Bunsen burner, or heating water in a kettle, or photosynthesis, or a braking cycle coming to a halt with the aid of friction.
In any natural process (we currently believe)
the total mass of the universe is unchanged…
but mass may be reconfigured
the total energy of the universe is unchanged…
but energy may be reconfigured; and
as mass and energy are associated, any reconfigurations of mass and energy are directly correlated.
So, in any change that involves energy transfers, there is an associated mass transfer (albeit usually one too small to notice or easily measure). We can, for example, calculate the (tiny) increase in mass due to water being heated in a kettle – and know just as the energy involved in heating the water came from somewhere else, there is an equivalent (tiny) decrease of mass somewhere else in the wider system (perhaps due to falling of water powering a hydroelectric power station). If we are boiling water to make a cup of tea, we may well be talking about a change in mass of the order of only 0.000 000 001 g according to my calculations for another posting.
The annihilation of the electron and positron is no different: there may be reconfigurations in the arrangement of mass and energy in the universe, but mass (and so energy) is conserved.
So, the question is, if the electron and positron, both massive particles (in the physics sense, that they have some mass) are annihilated, then where does their mass go if it is conserved? The answer is reflected in Prof. Martin's statement that "the particular kind of energy you get when you annihilate an electron and a positron is a photon, a particle of light". The mass is carried away by the photon.
The mass of a massless particle?
This may seem odd to those who have learnt that, unlike the electron and positron, the photon is massless. Strictly the photon has no rest mass, whereas the electron and positron do have rest mass – that is, they have inertial mass even when judged by an observer at rest in relation to them.
So, the photon only has 'no mass' when it is observed to be stationary – which nicely brings us back to Einstein who noted that electromagnetic radiation such as light could never appear to be at rest compared to the observer, as its very nature as a progressive electromagnetic wave would cease if one could travel alongside it at the same velocity. This led Einstein to conclude that the speed of light in any given medium was invariant (always the same for any observer), leading to his theory of special relativity.
So, a photon (despite having no 'rest' mass) not only carries energy, but also the associated mass.
Although we might think in terms of two particles being converted to a certain amount of energy as Prof. Martin suggests, this is slightly distorted thinking: the particles are converted to a different particle which now 'has' the mass from both, and so will also 'have' the energy associated with that amount of mass.
Mass is conserved during the electron-positron annihilation
A slight complication is that the electron and position are in relative motion when they annihilate, so there is some kinetic energy involved as well as the energy associated with their rest masses. But this does not change the logic of the general scheme. Just as there is an energy associated with the particles' rest masses, there is a mass component associated with their kinetic energy.
The total mass-energy equivalence before the annihilation has to include both the particle rest masses and their kinetic energy. The mass-energy equivalence afterwards (being conserved in any process) also reflects this. The energy of the photon (and the frequency of the radiation) reflects both the particle masses and their kinetic energies at the moment of the annihilation. The mass (being perfectly correlated with energy) carried away by the photon also reflects both the particle masses and their kinetic energies.
How could 'In Our Time' have improved the presentation?
It is easy to be critical of people doing their best to simplify complex topics. Any teacher knows that well-planned explanations can fail to get across key ideas as one is always reliant on what the audience already understands and thinks. Learners interpret what they hear and read in terms of their current 'interpretive resources' and habits of thinking.
A physicist or physics student hearing the episode would likely interpret Prof. Martin's statement within a canonical conceptual framework. However, someone holding the 'misconception' that mass is converted to energy in nuclear processes would likely interpret "they would annihilate into energy" as fitting, and reinforcing, that alternative conception.
I think a key issue here is a slippage that apparently refers to energy being formed in the annihilation, rather than radiation: (i.e., Prof. Martin could have said "they would annihilate into [radiation]"). When the positron and electron 'become' a photon, matter is changed to radiation – but it is not changed to energy, as matter has mass, and (as mass and energy have an equivalence) the energy is already there in the system.
Energy is reconfigured, but is not formed, in the annihilation process.
So, this whole essay is simply suggesting that a change of one word – from energy to radiation – could potentially avoid the formation of, or the reinforcing of, the alternative conception that mass is changed into energy in processes studied in particle physics. As experienced science teachers will know, sometimes such small shifts can make a good deal of difference to how we are interpreted and, so, what comes to be understood.
1 In what is often called a closed system there is no mass entering or leaving the system. However, energy can transfer to, or from, the system from its surroundings. Classically it might be assumed that the mass of a closed system is constant as the amount of matter is fixed, but Einstein realised that if there is a net energy influx to, or outflow from, the system, than some mass would also be transferred – even though no matter enters or leaves.
2 Perhaps in a uniform gravitational field, not subject to to any frictional forces, with an inextensible string supporting the bob, and in thermal equilibrium with its environment.
we are made of particles that have existed since the moment the universe began…those atoms travelled 14 billion years through time and space
The Big Bang Theory (but not quite the big bang theory).
What is the Big Bang Theory?
The big bang theory is a theory about the origin and evolution of the universe. Being a theory, it is conjectural, but it is the theory that is largely taken by scientists as our current best available account.
According to big bang theory, the entire universe started in a singularity, a state of infinite density and temperature, in which time space were created as well as matter. As the universe expanded it cooled to its present state – some, about, 13.8 billion years later.
Our current best understanding of the Cosmos is that the entire Universe was formed in a 'big bang' (Image by Gerd Altmann from Pixabay)
The term 'big bang' was originally intended as a kind of mockery – a sarcastic description of the notion – but the term was adopted by scientists, and has indeed become widely used in general culture.
Which brings me to 'The Big Bang Theory', which is said to have been the longest ever running sitcom ('situation comedy') – having been in production for longer than even 'Friends'.
The Big Bang Theory: Not science fiction, but fictional science? (Five of these characters have PhDs in science: one 'only' has a master's degree in engineering.)
A situation comedy is set around a situation. The situation was that two Cal Tech physicists are sharing an apartment. Leonard (basically a nice guy, but not very successful with women) is flatmate to Sheldon, a synaesthete, and kind of savant (a device on which to lever much of the humour) – a genius with an encyclopaedic knowledge of most areas of science but a deficient 'theory of mind' such that he lacks
insight into others, and so also
empathy, and
the ability to tell when people are using humour or being sarcastic to him.
If most physicists were like Sheldon we could understand why the big bang theory is still called the big bang theory even though the term was intended to be facetious. The show writers claim that Sheldon was not deliberately written to be on the autistic spectrum, but he tends to take statements literally: when it is suggested that he is crazy, he responds that he knows he is not as his mother had him tested as a child.
Sheldon (at right, partially in shot) has been widely recognised by viewers as showing signs of high-functioning Autism or Aspergers syndrome. (Still from The Big Bang Theory)
These guys hang out with Raj (Rajesh), an astrophysicist and Cambridge graduate so shy he is unable to speak to women, or indeed in their presence (presumably not a problem inherited from his father who is is a successful gynaecologist in India), and an engineer, Howard, who to my viewing is just an obnoxious creep with no obvious redeeming qualities. (But then I've not seen the full run.) When Howard becomes a NASA astronaut, he is bullied by the other astronauts, and whilst bullying is never acceptable, it is difficult to be too judgemental in his case.
This group are scientists, and they are 'nerds'. They watch science fiction and superhero movies, buy comic books and action figures, play competitive board games and acquire all the latests technical gadgets. And, apart from Sheldon (who has a strong belief in following a principled rigorous regime of personal hygiene that makes close contact with other humans seem repulsive) they try, and largely fail, to attract women.
In case this does not seem sufficiently stereotypical, the situation is complete when a young woman moves into in the flat opposite Leonard and Sheldon: Penny is the 'hot' new neighbour, who comes across as a 'dumb blonde' (she wants to be an actress – she is actually a waitress whilst she works at that), something of a hedonist, and not having the slightest knowledge of, or interest in, science. Penny's plan in life is to become a movie star, and her back-up plan is to become a television star.
If Sheldon and his friends tend to rather fetishise science and see it as inherently superior to other ways of engaging in the world, then Penny seems to reflect the other side of 'the two cultures' of C. P. Snow's famous lecture/essay that described an arts-science divide in mid-twentieth century British public life. That is, not only an acknowledged ignorance of scientific matters, but an ignorance that is almost worn as a badge of honour. Penny, of course, actually has a good deal of knowledge about many areas of culture that our 'heroes' are ignorant of.
Initially, Penny is the only lead female character in the show. This creates considerable ambiguity in how we are expected to see the show's representations of scientists during the early series. Is the viewer meant to be sharing their world where women are objects of recreation and sport and a distraction from the important business of the scientific quest? Or, is the audience being asked to laugh at these supposedly highly intelligent men who actually have such limited horizons?
Sheldon: I am a physicist. I have a working knowledge of the entire universe and everything it contains.
Penny. Who's Radiohead?
[pause]
Sheldon: I have a working knowledge of important things in the universe.
Penny has no interest in science
So, the premise is: can the nerdy, asthmatic, short-sighted, physicist win over the pretty, fun-loving, girl-next-door who is clearly seen to be 'out of his league'.
Spoiler alert
Do not read on if you wish to watch the show and find out for yourself. 😉
A marriage made in the heavens?
I recently saw an episode in series n (where n is a large positive integer) where Leonard and Penny decided to go to Las Vagas and get married. Leonard said he had written his own marriage vows – and it was these that struck me as problematic. My complaint was nothing to do with love and commitment, but just about physics.
Cal Tech physicist Leonard Hofstadter (played by Johnny Galecki) wrote his own vows for marriage to Penny (Kaley Cuoco) in 'The Big Bang Theory'
A non-physical love?
I made a note of Leonard's line:
"Penny, we are made of particles that have existed since the moment the universe began. I like to think those atoms travelled 14 billion years through time and space to create us so that we could be together and make each other whole."
Leonard declares his love
Sweet. But wrong.
Perhaps Leonard had been confused by the series theme music, the 'History of Everything', by the band Barenaked Ladies. The song begins well enough:
"Our whole universe was in a hot dense state
Then nearly fourteen billion years ago, expansion started…"
Lyrics to History of Everything (The Big Bang Theory Theme)
but in the second verse we are told
"As every galaxy was formed in less time than it takes to sing this song.
A fraction of a second and the elements were made."
Lyrics to History of Everything (The Big Bang Theory Theme)
which seems to reflect a couple of serious alternative conceptions.
So, the theme song seems to suggest that once the big bang had occurred, "nearly fourteen billion years ago", the elements were formed in a matter of seconds, and the galaxies in a matter of minutes. Leonard goes further, and suggests the atoms that he and Penny are comprised of have existed since "the moment the universe began". This is all contrary to the best understanding of physicists.
Surely Leonard, who defended his PhD thesis on particle physics, would know more about the canonical theories about the formation of those particles? (If not, he could ask Raj who once applied for a position in stellar evolution.)
The "hot dense state" was so hot that no particles could have condensed out. Certainly, some particles began to appear very soon after the big bang, but for much of the early 'history of everything' the only atoms that could exist were of the elements hydrogen, helium and lithium – as only the nuclei of these atoms were formed in the early universe.
The formation of heavier elements – carbon, oxygen, silicon and all the rest – occurred in stars – stars that did not exist until considerable cooling from the hot dense state had occurred. (See for example, 'A hundred percent conclusive science. Estimation and certainty in Maisie's galaxy'.) Most of the matter comprising Leonard, Penny, and the rest of us, does not reflect the few elements formed in the immediate aftermath of the big bang, but heavier elements that were formed billions of years later in stars that went supernovae and ejected material into space. 1 As has often been noted, we are formed from stardust.
"…So don't forget the human trial, The cry of love, the spark of life, dance thru the fire
Stardust we are Close to divine Stardust we are See how we shine"
From the lyrics to 'Stardust we are' (The Flower Kings – written by Roine Stolt and Tomas Bodin)
Does it matter – it is only pretend
Of course The Big Bang Theory (unlike the big bang theory) is not conjecture, but fiction. So, does it matter if it gets the science wrong? The Big Bang Theory is not meant to be science fiction, but a fiction that uses science to anchor it into a situation that will allow viewers to suspend disbelief.
Leonard is a believable character, but Sheldon is an extreme outlier. Howard and Raj are caricatures, exaggerations, as indeed are Amy (neurobiologist) and Bernadette (microbiologist) the other core characters introduced later.
But the series creators and writers seem to have made a real effort at most points in the show to make the science background authentic. Dialogue, whiteboard contents, projects, laboratory settings and the like seem to have been constructed with great care so that the scientifically literate viewer is comfortable with the context of the show. This authentic professional context offers the credible framework within which the sometimes incredible events of the characters' lives and relationships do not seem immediately ridiculous.
In that context, Leonard getting something so wrong seems incongruent.
Then again, he is in love, so perhaps his vows are meant to tell the scientifically literate viewer that there is a greater truth than even science – that in matters of the heart, poetic truth trumps even physics?
A Marillion song tells us:
A wise man once wrote That love is only An ancient instinct For reproduction Natural selection A wise man once said That everything could be explained And it's all in the brain
But as the same song asks: "where is the wisdom in that?"
Source cited:
Snow, C. P. (1959/1998). The Rede Lecture, 1959: The two cultures. In The Two Cultures (pp. 1-51). Cambridge University Press.
Note:
1 I was tempted to write 'most of the atoms'. Certainly most of the mass of a person is made up of atoms 2 that were formed a long time after the big bang. However, in terms of numbers of atoms, there are more of the (lightest) hydrogen atoms than of any other element: we are about 70% water, and water comprises molecules of H2O. So, that is getting close to half the atoms in us before we consider all the hydrogen in the fats and proteins and so forth.
2 That, of course, assumes the particles we are made of are atoms. Actually, we are comprised chemically of molecules and ions and relatively very, very few free atoms (those that are there are accidentally there in the sense they are not functional). No discrete atoms exist within molecules. So, to talk of the hydrogen atoms in us is to abstract the atoms from molecules and ions.
Leonard confuses matters (and matter) by referring initially to particles (which could be nucleons, quarks?) but then equating these to atoms – even though atoms are unlikely to float around for nearly 14 billion years without interacting with radiation and other matter to get ionised, form molecules, that may then dissociate, etc.
For many people reading this, I am making a pedantic point. When we talk of the atoms in a person's body, we do not actually mean atomsper se, but component parts of molecules of compounds of the element indicated by the atomreferred to*. A water molecule does not contain two hydrogen atoms and an oxygen atom, but it does contain two hydrogen atomic nuclei, and the core of an oxygen atom (its nucleus, and inner electron 'shell') within an 'envelope' of electrons.
* So, it is easier to use the shorthand: 'two atoms of hydrogen and one of oxygen'.
The reason it is sometimes important to be pedantic is that learners often think of a molecule as just a number of atoms stuck together and not as a new unitary entity composed of the same set of collective components but in a new configuration that gives it different properties. (For example, learners sometimes think the electrons in a covalent bond are still 'owned' by different atoms.) There is an associated common alternative conception here: the assumption of initial atomicity, where students tend to think of chemical processes as being interactions between atoms, even though reacting substances are very, very rarely atomic in nature.
This referred to an article in a recent issue of the magazine (May 2022, and also available on line) which proposed the slightly more subtle question 'Is fire a solid, liquid, gas, plasma – or something else entirely?'
This was an interesting and fun article, and I wondered how other readers might have responded.
An invitation
No one had commented on the article on line, so I offered my own comment, reproduced below. Before reading this, I would strongly recommend visiting the web-page and reading the original article – and considering how you would respond. (Indeed, if you wish, you can offer your own response there as a comment on the article.)
Ian Farrell (2022) asks: "Is fire a solid, liquid, gas, plasma – or something else entirely?" I suggest this is something of a trick question. It is 'something else', even if not 'something else entirely'.
It is perhaps not 'something else entirely' because fire involves mixtures of substances, and those substances may be describable in terms of the states of matter.
However, it is 'something else', because the classification into different states of matter strictly applies to pure samples of substances. It does not strictly apply to many mixtures: for example, honey, is mostly ('solid') sugar dissolved in ('liquid') water, but is itself neither a solid nor a liquid. Ditto jams, ketchup and so forth. Glass is in practical everyday terms a solid, obviously, but, actually, it flows and very old windows are thicker near their bottom edges. (Because glass does not have a regular molecular level structure, it does not have a definite point at which it freezes/melts.) Many plastics and waxes are not actually single substances (polymers often contain molecules of various chain lengths), so, again, do not have sharp melting points that give a clear solid-liquid boundary.
Fire, however, is not just outside the classification scheme as it involves a mixture (or even because it involves variations in mixture composition and temperature at different points in the flame), but because it is not something material, but a process.
Therefore, asking if fire is a solid, liquid, gas, or plasma could be considered an 'ontological category error' as processes are not the type of entities that the classification can be validly applied to.
You may wish to object that fire is only possible because there is material present. Yes, that is true. But, consider these questions:
Is photosynthesis a solid, liquid, gas, plasma…?
Is distillation a solid, liquid, gas, plasma…?
is the Haber process a solid, liquid, gas, plasma…?
is chromatography a solid, liquid, gas, plasma…?
Is fermentation a solid, liquid, gas, plasma… ?
Is melting a solid, liquid, gas, plasma…?
In each case the question does not make sense, as – although each involves substances, and these may individually, at least at particular points in the process, be classified by state of matter- these are processes and not samples of material.
Farrell hints at this in offering readers the clue "once the fuel or oxygen is exhausted, fire ceases to exist. But that isn't the case for solids, liquids or gases". Indeed, no, because a sample of material is not a process, and a process is not a sample of material.
I am sure I am only making a point that many readers of Education in Chemistry spotted immediately, but, unfortunately, I suspect many lay people (including probably some primary teachers charged with teaching science) would not have spotted this.
That was my response at Education in Chemistry, but I was also aware that it related to a wider issue about the nature of students' alternative conceptions.
Prof. Michelene Chi, a researcher at Arizona State University, has argued that a common factor in a wide range of student alternative conceptions relates to how they intuitively classify phenomena on 'ontological trees'.
"Ontological categories refer to the basic categories of realities or the kinds of existent in the world, such as concrete objects, events, and abstractions."
Chi, 2005, pp.163-164
We can think of all the things in the world as being classifiable on a series of branching trees. This is a very common idea in biology, where humans would appear in the animal kingdom, but more specifically among the Chordates, and more specifically still in the Mammalia class, and even more specifically still as Primates. Of course the animals branch could also be considered part of a living things tree. However, some children may think that animals and humans are inherently different types of living things – that they would be on different branches.
Some student alternative conceptions can certainly be understood in terms of getting typologies wrong. One example is how electron spin is often understood. For familiar objects, spin is a contingent property (the bicycle wheel may, or may not, be spinning – it depends…). Students commonly assume this applies to quanticles such as electrons, whereas electron spin is intrinsic – you cannot stop an electron 'spinning', as you could a cycle wheel, as spin is an inherent property of electrons. Just as you cannot take the charge away from an electron, nor can you remove its spin.
Two ways of classifying some electron properties (after Figures 8 and 9 in Taber, 2008). The top figure shows the scientific model; the bottom is a representation of a common student alternative conception.
Chi (2009) suggested three overarching (or overbranching?) distinct ontologial trees being entities, processes and mental states. These are fundamentally different types of category. The entities 'tree' encompasses a widely diverse range of things: furniture, cats, cathedrals, grains of salt, Rodin sculptures, iPads, tectonic plates, fossil shark teeth, Blue Peter badges, guitar picks, tooth picks, pick axes, large hadron colliders, galaxies, mitochondria….
Despite this diversity, all these entities are materials things, not be confused with, for example, a belief that burning is the release of phlogiston (a mental state) or the decolonisation of the curriculum (a process).
Chi suggested that often learners look to classify phenomena in science as types of material object, when they are actually processes. So, for example, children may consider heat is a substance that moves about, rather than consider heating as a process which leads to temperature changes. 1 Similarly 'electricity' may be seen as stuff, especailly when the term is undifferentiated by younger learners (being a blanket term relating to any electrical phenomenon). Chemical bonds are often thought of as material links, rather than processes that bind structures together. So, rather than covalent bonding being seen as an interaction between entities, it is seen as an entity (often as a 'shared pair of electrons').
Of course, science teachers (or at least the vast majority) do not make these errors. But any who do think that fire should be classifiable as one of the states of matter are making a similar, if less blatant, error of confusing matter and process. Chi's research suggests this is something we can easily tend to do, so it is not shameful – and Ian Farrell has done a useful service by highlighting this issue, and asking teachers to think about the matter…or rather, not the 'matter', but the process.
Work cited:
Chi, M. T. H. (2005). Commonsense Conceptions of Emergent Processes: Why Some Misconceptions Are Robust. Journal of the Learning Sciences, 14(2), 161-199. https://doi.org/10.1207/s15327809jls1402_1
Chi, M. T. (2009). Three types of conceptual change: Belief revision, mental model transformation, and categorical shift. In International handbook of research on conceptual change (pp. 89-110). Routledge.
Farrell, I. (2022). The burning question. Is fire a solid, liquid, gas, plasma – or something elkse entirely? Education in Chemistry, 59(3), 11.
A 'peer-reviewed' study claims to improve academic performance by purifying the souls of students suffering from hallucinations
Keith S. Taber
The research design is completely inadequate…the whole paper is confused…the methodology seems incongruous…there is an inconsistency…nowhere is the population of interest actually identified…No explanation of the discrepancy is provided…results of this analysis are not reported…the 'interview' technique used in the study is highly inadequate…There is a conceptual problem here…neither the validity nor reliability can be judged…the statistic could not apply…the result is not reported…approach is completely inappropriate…these tables are not consistent…the evidence is inconclusive…no evidence to demonstrate the assumed mechanism…totally unsupported claims…confusion of recommendations with findings…unwarranted generalisation…the analysis that is provided is useless…the research design is simply inadequate…no control condition…such a conclusion is irresponsible
Some issues missed in peer review for a paper in the European Journal of Education and Pedagogy
An invitation to publish without regard to quality?
I received an email from an open-access journal called the European Journal of Education and Pedagogy, with the subject heading 'Publish Fast and Pay Less' which immediately triggered the thought "another predatory journal?" Predatory journals publish submissions for a fee, but do not offer the editorial and production standards expected of serious research journals. In particular, they publish material which clearly falls short of rigorous research despite usually claiming to engage in peer review.
A peer reviewed journal?
Checking out the website I found the usual assurances that the journal used rigorous peer review as:
"The process of reviewing is considered critical to establishing a reliable body of research and knowledge. The review process aims to make authors meet the standards of their discipline, and of science in general.
We use a double-blind system for peer-reviewing; both reviewers and authors' identities remain anonymous to each other. The paper will be peer-reviewed by two or three experts; one is an editorial staff and the other two are external reviewers."
https://www.ej-edu.org/index.php/ejedu/about
Peer review is critical to the scientific process. Work is only published in (serious) research journals when it has been scrutinised by experts in the relevant field, and any issues raised responded to in terms of revisions sufficient to satisfy the editor.
I could not find who the editor(-in-chief) was, but the 'editorial team' of European Journal of Education and Pedagogy were listed as
Bea Tomsic Amon, University of Ljubljana, Slovenia
Chunfang Zhou, University of Southern Denmark, Denmark
Gabriel Julien, University of Sheffield, UK
Intakhab Khan, King Abdulaziz University, Saudi Arabia
Mustafa Kayıhan Erbaş, Aksaray University, Turkey
Panagiotis J. Stamatis, University of the Aegean, Greece
I decided to look up the editor based in England where I am also based but could not find a web presence for him at the University of Sheffield. Using the ORCID (Open Researcher and Contributor ID) provided on the journal website I found his ORCID biography places him at the University of the West Indies and makes no mention of Sheffield.
If the European Journal of Education and Pedagogy is organised like a serious research journal, then each submission is handled by one of this editorial team. However the reference to "editorial staff" might well imply that, like some other predatory journals I have been approached by (e.g., Are you still with us, Doctor Wu?), the editorial work is actually carried out by office staff, not qualified experts in the field.
That would certainly help explain the publication, in this 'peer-reviewed research journal', of the first paper that piqued my interest enough to motivate me to access and read the text.
The Effects of Using the Tazkiyatun Nafs Module on the Academic Achievement of Students with Hallucinations
The abstract of the paper published in what claims to be a peer-reviewed research journal
The paper initially attracted my attention because it seemed to about treatment of a medical condition, so I wondered was doing in an education journal. Yet, the paper seemed to also be about an intervention to improve academic performance. As I read the paper, I found a number of flaws and issues (some very obvious, some quite serious) that should have been spotted by any qualified reviewer or editor, and which should have indicated that possible publication should have been be deferred until these matters were satisfactorily addressed.
This is especially worrying as this paper makes claims relating to the effective treatment of a symptom of potentially serious, even critical, medical conditions through religious education ("a spiritual approach", p.50): claims that might encourage sufferers to defer seeking medical diagnosis and treatment. Moreover, these are claims that are not supported by any evidence presented in this paper that the editor of the European Journal of Education and Pedagogy decided was suitable for publication.
An overview of what is demonstrated, and what is claimed, in the study.
Limitations of peer review
Peer review is not a perfect process: it relies on busy human beings spending time on additional (unpaid) work, and it is only effective if suitable experts can be found that fit with, and are prepared to review, a submission. It is also generally more challenging in the social sciences than in the natural sciences. 1
That said, one sometimes finds papers published in predatory journals where one would expect any intelligent person with a basic education to notice problems without needing any specialist knowledge at all. The study I discuss here is a case in point.
Purpose of the study
Under the heading 'research objectives', the reader is told,
"In general, this journal [article?] attempts to review the construction and testing of Tazkiyatun Nafs [a Soul Purification intervention] to overcome the problem of hallucinatory disorders in student learning in secondary schools. The general objective of this study is to identify the symptoms of hallucinations caused by subtle beings such as jinn and devils among students who are the cause of disruption in learning as well as find solutions to these problems.
Meanwhile, the specific objective of this study is to determine the effect of the use of Tazkiyatun Nafs module on the academic achievement of students with hallucinations.
To achieve the aims and objectives of the study, the researcher will get answers to the following research questions [sic]:
Is it possible to determine the effect of the use of the Tazkiyatun Nafs module on the academic achievement of students with hallucinations?"
Awang, 2022, p.42
I think I can save readers a lot of time regarding the research question by suggesting that, in this study, at least, the answer is no – if only because the research design is completely inadequate to answer the research question. (I should point that the author comes to the opposite conclusion: e.g., "the approach taken in this study using the Tazkiyatun Nafs module is very suitable for overcoming the problem of this hallucinatory disorder", p.49.)
Indeed, the whole paper is confused in terms of what it is setting out to do, what it actually reports, and what might be concluded. As one example, the general objective of identifying "the symptoms of hallucinations caused by subtle beings such as jinn and devils" (but surely, the hallucinations are the symptoms here?) seems to have been forgotten, or, at least, does not seem to be addressed in the paper. 2
The study assumes that hallucinations are caused by subtle beings such as jinn and devils possessing the students. (Image by Tünde from Pixabay)
Methodology
So, this seems to be an intervention study.
Some students suffer from hallucinations.
This is detrimental to their education.
It is hypothesised that the hallucinations are caused by supernatural spirits ("subtle beings that lead to hallucinations"), so, a soul purification module might counter this detriment;
if so, sufferers engaging with the soul purification module should improve their academic performance;
and so the effect of the module is being tested in the study.
Thus we have a kind of experimental study?
No, not according to the author. Indeed, the study only reports data from a small number of unrepresentative individuals with no controls,
"The study design is a case study design that is a qualitative study in nature. This study uses a case study design that is a study that will apply treatment to the study subject to determine the effectiveness of the use of the planned modules and study variables measured many times to obtain accurate and original study results. This study was conducted on hallucination disorders [students suffering from hallucination disorders?] to determine the effectiveness of the Tazkiyatun Nafs module in terms of aspects of student academic achievement."
Awang, 2022, p.42
Case study?
So, the author sees this as a case study. Research methodologies are better understood as clusters of similar approaches rather than unitary categories – but case study is generally seen as naturalistic, rather than involving an intervention by an external researcher. So, case study seems incongruous here. Case study involves the detailed exploration of an instance (of something of interest – a lesson, a school, a course of tudy, a textbook, …) reported with 'thick description'.
The case is usually a complex phenomena which is embedded within a context from which is cannot readily be untangled (for example, a lesson always takes place within a wider context of a teacher working over time with a class on a course of study, within a curricular, and institutional, and wider cultural, context, all of which influence the nature of the specific lesson). So, due to the complex and embedded nature of cases, they are all unique.
"a case study is a study that is full of thoroughness and complex to know and understand an issue or case studied…this case study is used to gain a deep understanding of an issue or situation in depth and to understand the situation of the people who experience it"
Awang, 2022, p.42
A case is usually selected either because that case is of special importance to the researcher (an intrinsic case study – e.g., I studied this school because it is the one I was working in) or because we hope this (unique) case can tell us something about similar (but certainly not identical) other (also unique) cases. In the latter case [sic], an instrumental case study, we are always limited by the extent we might expect to be able to generalise beyond the case.
This limited generalisation might suggest we should not work with a single case, but rather look for a suitably representative sample of all cases: but we sometimes choose case study because the complexity of the phenomena suggests we need to use extensive, detailed data collection and analyses to understand the complexity and subtlety of any case. That is (i.e., the compromise we choose is), we decide we will look at one case in depth because that will at least give us insight into the case, whereas a survey of many cases will inevitably be too superficial to offer any useful insights.
So how does Awang select the case for this case study?
"This study is a case study of hallucinatory disorders. Therefore, the technique of purposive sampling (purposive sampling [sic]) is chosen so that the selection of the sample can really give a true picture of the information to be explored ….
Among the important steps in a research study is the identification of populations and samples. The large group in which the sample is selected is termed the population. A sample is a small number of the population identified and made the respondents of the study. A case or sample of n = 1 was once used to define a patient with a disease, an object or concept, a jury decision, a community, or a country, a case study involves the collection of data from only one research participant…
Awang, 2022, p.42
Of course, a case study of "a community, or a country" – or of a school, or a lesson, or a professional development programme, or a school leadership team, or a homework policy, or an enrichnment activity, or … – would almost certainly be inadequate if it was limited to "the collection of data from only one research participant"!
I do not think this study actually is "a case study of hallucinatory disorders [sic]". Leading aside the shift from singular ("a case study") to plural ("disorders"), the research does not investigate a/some hallucinatory disorders, but the effect of a soul purification module on academic performance. (Actually, spoiler alert 😉, it does not actually investigate the effect of a soul purification module on academic performance either, but the author seems to think it does.)
If this is a case study, there should be the selection ofa case, not a sample. Sometimes we do sample within a case in case study, but only from those identified as part of the case. (For example, if the case was a year group in a school, we may not have resources to interact in depth with several hundred different students). Perhaps this is pedantry as the reader likely knows what Awang meant by 'sample' in the paper – but semantics is important in research writing: a sample is chosen to represent a population, whereas the choice of case study is an acknowledgement that generalisation back to a population is not being claimed).
However, if "among the important steps in a research study is the identification of populations" then it is odd that nowhere in the paper is the population of interest actually specified!
Things slip our minds. Perhaps Awang intended to define the population, forgot, and then missed this when checking the text – buy, hey, that is just the kind of thing the reviewers and editor are meant to notice! Otherwise this looks very like including material from standard research texts to play lip-service to the idea that research-design needs to be principled, but without really appreciating what the phrases used actually mean. This impression is also given by the descriptions of how data (for example, from interviews) were analysed – but which are not reflected at all in the results section of the paper. (I am not accusing Awang of this, but because of the poor standard of peer review not raising the question, the author is left vulnerable to such an evaluation.)
The only one research participant?
So, what do we know about the "case or sample of n = 1 ", the "only one research participant" in this study?
The actual respondents in this case study related to hallucinatory disorders were five high school students. The supportive respondents in the case study related to hallucination disorders were five counseling teachers and five parents or guardians of students who were the actual respondents."
Awang, 2022, p.42
It is certainly not impossible that a case could comprise a group of five people – as long as those five make up a naturally bounded group – that is a group that a reasonable person would recognise as existing as a coherent entiy as they clearly had something in common (they were in the same school class, for example; they were attending the same group therapy session, perhaps; they were a friendship group; they were members of the same extended family diagnosed with hallucinatory disorders…something!) There is no indication here of how these five make up a case.
The identification of the participants as a case might have made sense had the participants collectively undertaken the module as a group, but the reader is told: "This study is in the form of a case study. Each practice and activity in the module are done individually" (p.50). Another justification could have been if the module had been offered in one school, and these five participants were the students enrolled in the programme at that time but as "analysis of the respondents' academic performance was conducted after the academic data of all respondents were obtained from the respective respondent's school" (p.45) it seems they did not attend a single school.
The results tables and reports in the text refer to "respondent 1" to "respondent 4". In case study, an approach which recognises the individuality and inherent value of the particular case, we would usually assign assumed names to research participants, not numbers. But if we are going to use numbers, should there not be a respondent 5?
The other one research participant?
It seems that these is something odd here.
Both the passage above, and the abstract refer to five respondents. The results report on four. So what is going on? No explanation of the discrepancy is provided. Perhaps:
There only ever were four participants, and the author made a mistake in counting.
There only ever were four participants, and the author made a typographical mistake (well, strictly, six typographical mistakes) in drafting the paper, and then missed this in checking the manuscript.
There were five respondents and the author forgot to include data on respondent 5 purely by accident.
There were five respondents, but the author decided not to report on the fifth deliberately for a reason that is not revealed (perhaps the results did not fit with the desired outcome?)
The significant point is not that there is an inconsistency but that this error was missed by peer reviewers and the editor – if there ever was any genuine peer review. This is the kind of mistake that a school child could spot – so, how is it possible that 'expert reviewers' and 'editorial staff' either did not notice it, or did not think it important enough to query?
Research instruments
Another section of the paper reports the instrumentation used in the paper.
"The research instruments for this study were Takziyatun Nafs modules, interview questions, and academic document analysis. All these instruments were prepared by the researcher and tested for validity and reliability before being administered to the selected study sample [sic, case?]."
Awang, 2022, p.42
Of course, it is important to test instruments for validity and reliability (or perhaps authenticity and trustworthiness when collecting qualitative data). But it is also important
to tell the reader how you did this
to report the outcomes
which seems to be missing (apart from in regard to part of the implemented module – see below). That is, the reader of a research study wants evidence not simply promises. Simply telling readers you did this is a bit like meeting a stranger who tells you that you can trust them because they (i.e., say that they) are honest.
Later the reader is told that
"Semi- structured interview questions will be [sic, not 'were'?] developed and validated for the purpose of identifying the causes and effects of hallucinations among these secondary school students…
…this interview process will be [sic, not 'was'] conducted continuously [sic!] with respondents to get a clear and specific picture of the problem of hallucinations and to find the best solution to overcome this disorder using Islamic medical approaches that have been planned in this study
Awang, 2022, pp.43-44
At the very least, this seems to confuse the plan for the research with a report of what was done. (But again, apparently, the reviewers and editorial staff did not think this needed addressing.) This is also confusing as it is not clear how this aspect of the study relates to the intervention. Were the interviews carried out before the intervention to help inform the design of the modules (presumably not as they had already been "tested for validity and reliability before being administered to the selected study sample"). Perhaps there are clear and simple answers to such questions – but the reader will not know because the reviewers and editor did not seem to feel they needed to be posed.
If "Interviews are the main research instrument in this study" (p.43), then one would expect to see examples of the interview schedules – but these are not presented. The paper reports a complex process for analysing interview data, but this is not reflected in the findings reported. The readers is told that the six stage process leads to the identifications and refinement of main and sub-categories. Yet, these categories are not reported in the paper. (But, again, peer reviewers and the editor did not apparently raise this as something to be corrected.) More generally "data analysis used thematic analysis methods" (p.44), so why is there no analysis presented in terms of themes? The results of this analysis are simply not reported.
The reader is told that
"This interview method…aims to determine the respondents' perspectives, as well as look at the respondents' thoughts on their views on the issues studied in this study."
Awang, 2022, p.44
But there is no discussion of participants perspectives and views in the findings of the study. 2Did the peer reviewers and editor not think this needed addressing before publication?
Even more significantly, in a qualitative study where interviews are supposedly the main research instrument, one would expect to see extracts from the interviews presented as part of the findings to support and exemplify claims being made: yet, there are none. (Did this not strike the peer reviewers and editor as odd: presumably they are familiar with the norms of qualitative research?)
The only quotation from the qualitative data (in this 'qualitative' study) I can find appears in the implications section of the paper:
"Are you aware of the importance of education to you? Realize. Is that lesson really important? Important. The success of the student depends on the lessons in school right or not? That's right"
Respondent 3: Awang, 2022, p.49
This seems a little bizarre, if we accept this is, as reported, an utterance from one of the students, Respondent 3. It becomes more sensible if this is actually condensed dialogue:
"Are you aware of the importance of education to you?"
"Realize."
"Is that lesson really important?"
"Important."
"The success of the student depends on the lessons in school right or not?"
"That's right"
It seems the peer review process did not lead to suggesting that the material should be formatted according to the norms for presenting dialogue in scholarly texts by indicating turns. In any case, if that is typical of the 'interview' technique used in the study then it is highly inadequate, as clearly the interviewer is leading the respondent, and this is more an example of indoctrination than open-ended enquiry.
Random sampling of data
Completely incongruous with the description of the purposeful selection of the participants for a case study is the account of how the assessment data was selected for analysis:
"The process of analysis of student achievement documents is carried out randomly by taking the results of current examinations that have passed such as the initial examination of the current year or the year before which is closest to the time of the study."
Awang, 2022, p.44
Did the peer reviewers or editor not question the use of the term random here? It is unclear what is meant to by 'random' here, but clearly if the analysis was based on randomly selected data that would undermine the results.
Validating the soul purification module
There is also a conceptual problem here. The Takziyatun Nafs modules are the intervention materials (part of what is being studied) – so they cannot also be research instruments (used to study them). Surely, if the Takziyatun Nafs modules had been shown to be valid and reliable before carrying out the reported study, as suggested here, then the study would not be needed to evaluate their effectiveness. But, presumably, expert peer reviewers (if there really were any) did not see an issue here.
The reliability of the intervention module
The Takziyatun Nafs modules had three components, and the author reports the second of the three was subjected to tests of validity and reliability. It seems that Awang thinks that this demonstrates the validity and reliability of the complete intervention,
"The second part of this module will go through [sic] the process of obtaining the validity and reliability of the module. Proses [sic] to obtain this validity, a questionnaire was constructed to test the validity of this module. The appointed specialists are psychologists, modern physicians (psychiatrists), religious specialists, and alternative medicine specialists. The validity of the module is identified from the aspects of content, sessions, and activities of the Tazkiyatun Nafs module. While to obtain the value of the reliability coefficient, Cronbach's alpha coefficient method was used. To obtain this Cronbach's alpha coefficient, a pilot test was conducted on 50 students who were randomly selected to test the reliability of this module to be conducted."
Awang, 2022, pp.43-44
Now to unpack this, it may be helpful to briefly outline what the intervention involved (as as the paper is open access anyone can access and read the full details in the report).
From the MGM film 'A Night at the Opera' (1935): "The introduction of the module will elaborate on the introduction, rationale, and objectives of this module introduced"
The description does not start off very helpfully ("The introduction of the module will elaborate on the introduction, rationale, and objectives of this module introduced" (p.43) put me in mind of the Marx brothers: "The party of the first part shall be known in this contract as the party of the first part"), but some key points are,
"the Tazkiyatun Nafs module was constructed to purify the heart of each respondent leading to the healing of hallucinatory disorders. This liver purification process is done in stages…
"the process of cleansing the patient's soul will be done …all the subtle beings in the patient will be expelled and cleaned and the remnants of the subtle beings in the patient will be removed and washed…
The second process is the process of strengthening and the process of purification of the soul or heart of the patient …All the mazmumah (evil qualities) that are in the heart must be discarded…
The third process is the process of enrichment and the process of distillation of the heart and the practices performed. In this process, there will be an evaluation of the practices performed by the patient as well as the process to ensure that the patient is always clean from all the disturbances and disturbances [sic] of subtle beings to ensure that students will always be healthy and clean from such disturbances…
Awang, 2022, p.45, p.43
Quite how this process of exorcising and distilling and cleansing will occur is not entirely clear (and if the soul is equated with the heart, how is the liver involved?), but it seems to involve reflection and prayer and contemplation of scripture – certainly a very personal and therapeutic process.
And yet its validity and reliability was tested by giving a questionnaire to 50 students randomly selected (from the unspecified population, presumably)? No information is given on how a random section was made (Taber, 2013) – which allows a reader to be very sceptical that this actually was a random sample from the (un?)identified population, and not just an arbitrary sample of 50 students. (So, that is twice the word 'random' is used in the paper when it seems inappropriate.)
It hardly matters here, as clearly neither the validity nor the reliability of a spiritual therapy can be judged from a questionnaire (especially when administered to people who have never undertaken the therapy). In any case, the "reliability coefficient" obtained from an administration of a questionnaire ONLY applies to that sample on that occasion. So, the statistic could not apply to the four participants in the study. And, in any case, the result is not reported, so the reader has no idea what the value of Cronbach's alpha was (but then, this was described as a qualitative study!)
Moreover, Cronbach's alpha only indicates the internal coherence of the items on a scale (Taber, 2019): so, it only indicates whether the set of questions included in the questionnaire seem to be accessing the same underlying construct in motivating the responses of those surveyed across the set of items. It gives no information about the reliability of the instrument (i.e., whether it would give the same results on another occasion).
This approach to testing validity and reliability is then completely inappropriate and unhelpful. So, even if the outcomes of the testing had been reported (and they are not) they would not offer any relevant evidence. Yet it seems that peer reviewers and editor did not think to question why this section was included in the paper.
Ethical issues
A study of this kind raises ethical issues. It may well be that the research was carried out in an entirely proper and ethical manner, but it is usual in studies with human participants ('human subjects') to make this clear in the published report (Taber, 2014b). A standard issue is whether the participants gave voluntary, informed, consent. This would mean that they were given sufficient information about the study at the outset to be able to decide if they wished to participate, and were under no undue pressure to do so. The 'respondents' were school students: if they were considered minors in the research context (and oddly for a 'case study' such basic details as age and gender are not reported) then parental permission would also be needed, again subject to sufficient briefing and no duress.
However, in this specific research there are also further issues due to the nature of the study. The participants were subject to medical disorders, so how did the researcher obtain information about, and access to, the students without medical confidentiality being broken? Who were the 'gatekeepers' who provided access to the children and their personal data? The researcher also obtained assessment data "from the class teacher or from the Student Affairs section of the student's school" (p.44), so it is important to know that students (and parents/guardians) consented to this. Again, peer review does not seem to have identified this as an issue to address before publication.
There is also the major underlying question about the ethics of a study when recognising that these students were (or could be, as details are not provided) suffering from serious medical conditions, but employing religious education as a treatment ("This method of treatment is to help respondents who suffer from hallucinations caused by demons or subtle beings", p.44). Part of the theoretical framework underpinning the study is the assumption that what is being addressed is"the problem of hallucinations caused by the presence of ethereal beings…" (p.43) yet it is also acknowledged that,
"Hallucinatory disorders in learning that will be emphasized in this study are due to several problems that have been identified in several schools in Malaysia. Such disorders are psychological, environmental, cultural, and sociological disorders. Psychological disorders such as hallucinatory disorders can lead to a more critical effect of bringing a person prone to Schizophrenia. Psychological disorders such as emotional disorders and psychiatric disorders. …Among the causes of emotional disorders among students are the school environment, events in the family, family influence, peer influence, teacher actions, and others."
Awang, 2022, p.41
There seem to be three ways of understanding this apparent discrepancy, which I might gloss:
there are many causes of conditions that involve hallucinations, including, but not only, possession by evil or mischievousness spirits;
the conditions that lead to young people having hallucinations may be understood at two complementary levels, at a spiritual level in terms of a need for inner cleansing and exorcising of subtle beings, and in terms of organic disease or conditions triggered by, for example, social and psychological factors;
in the introduction the author has relied on various academic sources to discuss the nature of the phenomenon of students having hallucinations, but he actually has a working assumption that is completely different: hallucinations are due to the presence of jinn or other spirits.
I do not think it is clear which of these positions is being taken by the study's author.
In the first case it would be necessary to identify which causes are present in potential respondents and only recruit those suffering possession for this study (which does not seem to have been done);
In the second case, spiritual treatment would need to complement medical intervention (which would completely undermine the validity of the study as medical treatments for the underlying causes of hallucinations are likely to be the cause of hallucinations ceasing, not the tested intervention);
The third position is clearly problematic in terms of academic scholarship as it is either completely incompetent or deliberately disregards academic norms that require the design of a study to reflect the conceptual framework set out to motivate it.
So, was this tested intervention implemented instead of or alongside formal medical intervention?
If it was alongside medical treatment, then that raises a major confound for the study.
Yet it would clearly be unacceptable to deny sufferers indicated medical treatment in order to test an educational intervention that is in effect a form of exorcism.
Again, it may be there are simple and adequate responses to these questions (although here I really cannot see what they might be), but unfortunately it seems the journal referees and editor did not think to ask for them.
Findings
Results tables presented in Awang, 2022 (p.45) [Published with a creative commons licence allowing reproduction]: "Based on the findings stated in Table I show that serial respondents experienced a decline in academic achievement while they face the problem of hallucinations. In contrast to Table II which shows an improvement in students' academic achievement after hallucinatory disorders can be resolved." If we assume that columns in the second table have been mislabelled, then it seems the school performance of these four students suffered while they were suffering hallucinations, but improved once they recovered. From this, we can infer…?
The key findings presented concern academic performance at school. Core results are presented in tables I and II. Unfortunately these tables are not consistent as they report contradictory results for the academic performance of students before and during periods when they had hallucinations.
They can be made consistent if the reader assumes that two of the columns in table II are mislabelled. If the reader assumes that the column labelled 'before disruption' actually reports the performance 'during disruption' and that the column actually labelled 'during disruption' is something else, then they become consistent. For the results to tell a coherent story and agree with the author's interpretation this 'something else' presumably should be 'after disruption'.
This is a very unfortunate error – and moreover one that is obvious to any careful reader. (So, why was it not obvious to the referees and editor?)
As well as looking at these overall scores, other assessment data is presented separately for each of respondent 1 – respondent 4. Theses sections comprise presentations of information about grades and class positions, mixed with claims about the effects of the intervention. These claims are not based on any evidence and in many cases are conclusions about 'respondents' in general although they are placed in sections considering the academic assessment data of individual respondents. So,there are a number of problems with these claims:
they are of the nature of conclusions, but appear in the section presenting the findings;
they are about the specific effects of the intervention that the author assumes has influenced academic performance, not the data analysed in these sections;
they are completely unsubstantiated as no data or analysis is offered to support them;
often they make claims about 'respondents' in general, although as part of the consideration of data from individual learners.
Despite this, the paper passed peer-review and editorial scrutiny.
Rhetorical research?
This paper seems to be an example of a kind of 'rhetorical research' where a researcher is so convinced about their pre-existant theoretical commitments that they simply assume they have demonstrated them. Here the assumption seem to be:
Recovering from suffering hallucinations will increase student performance
Hallucinations are caused by jinn and devils
A spiritual intervention will expel jinn and devils
So, a spiritual intervention will cure hallucinations
So, a spiritual intervention will increase student performance
The researcher provided a spiritual intervention, and the student performance increased, so it is assumed that the scheme is demonstrated. The data presented is certainly consistent with the assumption, but does not in itself support this scheme without evidence. Awang provides evidence that student performance improved in four individuals after they had received the intervention – but there is no evidence offered to demonstrate the assumed mechanism.
A gardener might think that complimenting seedlings will cause them to grow. Perhaps she praises her seedlings every day, and they do indeed grow. Are we persuaded about the efficacy of her method, or might we suspect another cause at work? Would the peer-reveiewers and editor of the European Journal of Education and Pedagogy be persuaded this demonstrated that compliments cause plant growth? On the evidence of this paper, perhaps they would.
This is what Awang tells readers about the analysis undertaken:
Each student respondent involved in this study [sic, presumably not, rather the researcher] will use the analysis of the respondent's performance to determine the effect of hallucination disorders on student achievement in secondary school is accurate.
The elements compared in this analysis are as follows: a) difference in mean percentage of achievement by subject, b) difference in grade achievement by subject and c) difference in the grade of overall student achievement. All academic results of the respondents will be analyzed as well as get the mean of the difference between the performance before, during, and after the respondents experience hallucinations.
These results will be used as research material to determine the accuracy of the use of the Tazkiyatun Nafs Module in solving the problem of hallucinations in school and can improve student achievement in academic school."
Awang, 2022, p.45
There is clearly a large jump between the analysis outlined in the second paragraph here, and testing the study hypotheses as set out in the final paragraph. But the author does not seem to notice this (and more worryingly, nor do the journal's reviewers and editor).
So interleaved into the account of findings discussing "mean percentage of achievement by subject…difference in grade achievement by subject…difference in the grade of overall student achievement" are totally unsupported claims. Here is an example for Respondent 1:
"Based on the findings of the respondent's achievement in the grade for Respondent 1 while facing the problem of hallucinations shows that there is not much decrease or deterioration of the respondent's grade. There were only 4 subjects who experienced a decline in grade between before and during hallucination disorder. The subjects that experienced decline were English, Geography, CBC, and Civics. Yet there is one subject that shows a very critical grade change the Civics subject. The decline occurred from grade A to grade E. This shows that Civics education needs to be given serious attention in overcoming this problem of decline. Subjects experiencing this grade drop were subjects involving emotion, language, as well as psychomotor fitness. In the context of psychology, unstable emotional development leads to a decline in the psychomotor and emotional development of respondents.
After the use of the Tazkiyatun Nafs module in overcoming this problem, hallucinatory disorders can be overcome. This situation indicates the development of the respondents during and after experiencing hallucinations after practicing the Tazkiyatun Nafs module. The process that takes place in the Tzkiyatun Nafs module can help the respondent to stabilize his emotions and psyche for the better. From the above findings there were 5 subjects who experienced excellent improvement in grades. The increase occurred in English, Malay, Geography, and Civics subjects. The best improvement is in the subject of Civic education from grade E to grade B. The improvement in this language subject shows that the respondents' emotions have stabilized. This situation is very positive and needs to be continued for other subjects so that respondents continue to excel in academic achievement in school.""
Awang, 2022, p.45 (emphasis added)
The material which I show here as underlined is interjected completely gratuitously. It does not logically fit in the sequence. It is not part of the analysis of school performance. It is not based on any evidence presented in this section. Indeed, nor is it based on any evidence presented anywhere else in the paper!
This pattern is repeated in discussing other aspects of respondents' school performance. Although there is mention of other factors which seem especially pertinent to the dip in school grades ("this was due to the absence of the respondents to school during the day the test was conducted", p.46; "it was an increase from before with no marks due to non-attendance at school", p.46) the discussion of grades is interspersed with (repetitive) claims about the effects of the intervention for which no evidence is offered.
Respondent 1
Respondent 2
Respondent 3
Respondent 4
§: Differences in Respondents' Grade Achievement by Subject
"After the use of the Tazkiyatun Nafs module in overcoming this problem, hallucinatory disorders can be overcome. This situation indicates the development of the respondents during and after experiencing hallucinations after practicing the Tazkiyatun Nafs module. The process that takes place in the Tzkiyatun Nafs module can help the respondent to stabilize his emotions and psyche for the better." (p.45)
"After the use of the Tazkiyatun Nafs module as a soul purification module, showing the development of the respondents during and after experiencing hallucination disorders is very good. The process that takes place in the Tzkiyatun Nafs module can help the respondent to stabilize his emotions and psyche for the better." (p.46)
"The process that takes place in the Tazkiyatun Nafs module can help the respondent to stabilize his emotions and psyche for the better" (p.46)
"The process that takes place in the Tazkiyatun Nafs module can help the respondent to stabilize his emotions and psyche for the better." (p.46)
§:Differences in Respondent Grades according to Overall Academic Achievement
"Based on the findings of the study after the hallucination disorder was overcome showed that the development of the respondents was very positive after going through the treatment process using the Tazkiyatun Nafs module…In general, the use of Tazkiyatun Nafs module successfully changed the learning lifestyle and achievement of the respondents from poor condition to good and excellent achievement." (pp.46-7)
"Based on the findings of the study after the hallucination disorder was overcome showed that the development of the respondents was very positive after going through the treatment process using the Tazkiyatun Nafs module. … This excellence also shows that the respondents have recovered from hallucinations after practicing the methods found in the Tazkiayatun Nafs module that has been introduced. In general, the use of the Tazkiyatun Nafs module successfully changed the learning lifestyle and achievement of the respondents from poor condition to good and excellent achievement." (p.47)
"Based on the findings of the study after the hallucination disorder was overcome showed that the development of the respondents was very positive after going through the treatment process using the Tazkiyatun Nafs module…In general, the use of the Tazkiyatun Nafs module successfully changed the learning lifestyle and achievement of the respondents from poor condition to good and excellent achievement." (p.47)
"Based on the findings of the study after the hallucination disorder was overcome showed that the development of the respondents was very positive after going through the treatment process using the Tazkiyatun Nafs module…In general, the use of the Tazkiyatun Nafs module has successfully changed the learning lifestyle and achievement of the respondents from poor condition to good and excellent achievement." (p.47)
Unsupported claims made within findings sections reporting analyses of individual student academic grades: note (a) how these statements included in the analysis of individual school performance data from four separate participants (in a case study – a methodology that recognises and values diversity and individuality) are very similar across the participants; (b) claims about 'respondents' (plural) are included in the reports of findings from individual students.
Awang summarises what he claims the analysis of 'differences in respondents' grade achievement by subject' shows:
"The use of the Tazkiyatun Nafs module in this study helped the students improve their respective achievement grades. Therefore, this soul purification module should be practiced by every student to help them in stabilizing their soul and emotions and stay away from all the disturbances of the subtle beings that lead to hallucinations"
Awang, 2022, p.46
And, on the next page, Awang summarises what he claims the analysis of 'differences in respondent grades according to overall academic achievement' shows:
"The use of the Tazkiyatun Nafs module in this study helped the students improve their respective overall academic achievement. Therefore, this soul purification module should be practiced by every student to help them in stabilizing the soul and emotions as well as to stay away from all the disturbances of the subtle beings that lead to hallucination disorder."
Awang, 2022, p.47
So, the analysis of grades is said to demonstrate the value of the intervention, and indeed Awang considers this is reason to extend the intervention beyond the four participants, not just to others suffering hallucinations, but to "every student". The peer review process seems not to have raised queries about
the unsupported claims,
the confusion of recommendations with findings (it is normal to keep to results in a findings section), nor
the unwarranted generalisation from four hallucination suffers to all students whether healthy or not.
Interpreting the results
There seem to be two stories that can be told about the results:
When the four students suffered hallucinations, this led to a deterioration in their school performance. Later, once they had recovered from the episodes of hallucinations, their school performance improved.
Narrative 1
Now narrative 1 relies on a very substantial implied assumption – which is that the numbers presented as school performance are comparable over time. So, a control would be useful: such as what happened to the performance scores of other students in the same classes over the same time period. It seems likely they would not have shown the same dip – unless the dip was related to something other than hallucinations – such as the well-recognised dip after long school holidays, or some cultural distraction (a major sports tournament; fasting during Ramadan; political unrest; a pandemic…). Without such a control the evidence is suggestive (after all, being ill, and missing school as a result, is likely to lead to a dip in school performance, so the findings are not surprising), but inconclusive.
Intriguingly, the author tells readers that "student achievement statistics from the beginning of the year to the middle of the current [sic, published in 2022] year in secondary schools in Northern Peninsular Malaysia that have been surveyed by researchers show a decline (Sabri, 2015 [sic])" (p.42), but this is not considered in relation to the findings of the study.
When the four students suffered hallucinations, this led to a deterioration in their school performance. Later, as a result of undergoing the soul purification module, their school performance improved.
Narrative 2
Clearly narrative 2 suffers from the same limitation as narrative 1. However, it also demands an extra step in making an inference. I could re-write this narrative:
When the four students suffered hallucinations, this led to a deterioration in their school performance. Later, once they had recovered from the episodes of hallucinations, their school performance improved. AND the recovery was due to engagement with the soul purification module.
Narrative 2'.
That is, even if we accept narrative 1 as likely, to accept narrative 2 we would also need to be convinced that:
a) sufferers from medical conditions leading to hallucinations do not suffer periodic attacks with periods of remission in between; or
b) episodes of hallucinations cannot be due to one-off events (emotional trauma, T.I.A. {transient ischaemic attack or mini-strokes},…) that resolve naturally in time; or
c) sufferers from medical conditions leading to hallucinations do not find they resolve due to maturation; or
d) the four participants in this study did not undertaken any change in life-style (getting more sleep, ceasing eating strange fungi found in the woods) unrelated to the intervention that might have influenced the onset of hallucinations; or
e) the four participants in this study did not receive any medical treatment independent of the intervention (e.g., prescribed medication to treat migraine episodes) that might have influenced the onset of hallucinations
Despite this study being supposedly a case study (where the expectation is there should be 'thick description' of the case and its context), there is no information to help us exclude such options. We do not know the medical diagnoses of the conditions causing the participants' hallucinations, or anything about their lives or any medical treatment that may have been administered. Without such information, the analysis that is provided is useless for answering the research question.
In effect, regardless of all the other issues raised, the key problem is that the research design is simply inadequate to test the research question. But it seems the referees and editor did not notice this shortcoming.
Alleged implications of the research
After presenting his results Awang draws various implications, and makes a number of claims about what had been found in the study:
"After the students went through the treatment session by using the Tazkiayatun Nafsmodule to treat hallucinations, it showed a positive effect on the student respondents. All this was certified by the expert, the student's parents as well as the counselor's teacher." (p.48)
"Based on these findings, shows that hallucinations are very disturbing to humans and the appropriate method for now to solve this problem is to use the Tazkiyatun Nafs Module." (p.48)
"…the use of the Tazkiyatun Nafs module while the respondent is suffering from hallucination disorder is very appropriate…is very helpful to the respondents in restoring their minds and psyche to be calmer and healthier. These changes allow students to focus on their studies as well as allow them to improve their academic performance better." (p.48)
"The use of the Tazkiyatun Nafs Module in this study has led to very positive changes there are attitudes and traits of students who face hallucinations before. All the negative traits like irritability, loneliness, depression,etc. can be overcome completely." (p.49)
"The personality development of students is getting better and perfect with the implementation of the Tazkiaytun Nafs module in their lives." (p.49)
"Results indicate that students who suffer from this hallucination disorder are in a state of high depression, inactivity, fatigue, weakness and pain,and insufficient sleep." (p.49)
"According to the findings of this study, the history of this hallucination disorder started in primary school and when a person is in adolescence, then this disorder becomes stronger and can cause various diseases and have various effects on a person who is disturbed." (p.50)
Given the range of interview data that Awang claims to have collected and analysed, at least some of the claims here are possibly supported by the data. However, none of this data and analysis is available to the reader. 2 These claims are not supported by any evidence presented in the paper. Yet peer reviewers and the editor who read the manuscript seem to feel it is entirely acceptable to publish such claims in a research paper, and not present any evidence whatsoever.
Summing up
In summary: as far as these four students were concerned (but not perhaps the fifth participant?), there did seem to be a relationship between periods of experiencing hallucinations and lower school performance (perhaps explained by such factors as "absenteeism to school during the day the test was conducted" p.46) ,
"the performance shown by students who face chronic hallucinations is also declining and declining. This is all due to the actions of students leaving the teacher's learning and teaching sessions as well as not attending school when this hallucinatory disorder strikes. This illness or disorder comes to the student suddenly and periodically. Each time this hallucination disease strikes the student causes the student to have to take school holidays for a few days due to pain or depression"
Awang, 2022, p.42
However,
these four students do not represent any wider population;
there is no information about the specific nature, frequency, intensity, etcetera, of the hallucinations or diagnoses in these individuals;
there was no statistical test of significance of changes; and
there was no control condition to see if performance dips were experienced by others not experiencing hallucinations at the same time.
Once they had recovered from the hallucinations (and it is not clear on what basis that judgement was made) their scores improved.
The author would like us to believe that the relief from the hallucinations was due to the intervention, but this seems to be (quite literally) an act of faith 3 as no actual research evidence is offered to show that the soul purification module actually had any effect. It is of course possible the module did have an effect (whether for the conjectured or other reasons – such as simply offering troubled children some extra study time in a calm and safe environment and special attention – or because of an expectancy effect if the students were told by trusted authority figures that the intervention would lead to the purification of their hearts and the healing of their hallucinatory disorder) but the study, as reported, offers no strong grounds to assume it did have such an effect.
An irresponsible journal
As hallucinations are often symptoms of organic disease affecting blood supply to the brain, there is a major question of whether treating the condition by religious instruction is ethically sound. For example, hallucinations may indicate a tumour growing in the brain. Yet, if the module was only a complement to proper medical attention, a reader may prefer to suspect that any improvement in the condition (and consequent increased engagement in academic work) may have been entirely unrelated to the module being evaluated.
Indeed, a published research study that claims that soul purification is a suitable treatment for medical conditions presenting with hallucinations is potentially dangerous as it could lead to serious organic disease going untreated. If Awang's recommendations were widely taken up in Malaysia such that students with serious organic conditions were only treated for their hallucinations by soul purification rather than with medication or by surgery it would likely lead to preventable deaths. For a research journal to publish a paper with such a conclusion, where any qualified reviewer or editor could easily see the conclusion is not warranted, is irresponsible.
As the journal website points out,
"The process of reviewing is considered critical to establishing a reliable body of research and knowledge. The review process aims to make authors meet the standards of their discipline, and of science in general."
https://www.ej-edu.org/index.php/ejedu/about
So, why did the European Journal of Education and Pedagogy not subject this submission to meaningful review to help the author of this study meet the standards of the discipline, and of science in general?
Work cited:
Awang, S. B. (2022). Hallucination Disorders: The Effects of Using the Tazkiyatun Nafs Module on the Academic Achievement of Students with Hallucinations. European Journal of Education and Pedagogy, 3(4), 41-51.
Taber, K. S. (2014b). Ethical considerations of chemistry education research involving "human subjects".Chemistry Education Research and Practice, 15(2), 109-113. [Free access]
1 In mature fields in the natural sciences there are recognised traditions ('paradigms', 'disciplinary matrices') in any active field at any time. In general (and of course, there will be exceptions):
at any historical time, there is a common theoretical perspective underpinning work in a research programme, aligned with specific ontological and epistemological commitments;
at any historical time, there is a strong alignment between the active theories in a research programme and the acceptable instrumentation, methodology and analytical conventions.
Put more succinctly, in a mature research field, there is generally broad agreement on how a phenomenon is to be understood; and how to go about investigating it, and how to interpret data as research evidence.
This is generally not the case in educational research – which is in part at least due to the complexity and, so, multi-layered nature, of the phenomena studied (Taber, 2014a): phenomena such as classroom teaching. So, in reviewing educational papers, it is sometimes necessary to find different experts to look at the theoretical and the methodological aspects of the same submission.
2 The paper is very strange in that the introductory sections and the conclusions and implications sections have a very broad scope, but the actual research results are restricted to a very limited focus: analysis of school test scores and grades.
It is as if as (and could well be that) a dissertation with a number of evidential strands has been reduced to a paper drawing upon only one aspect of the research evidence, but with material from other sections of the dissertation being unchanged from the original broader study.
3 Readers are told that
"All these acts depend on the sincerity of the medical researcher or fortune-teller seeking the help of Allah S.W.T to ensure that these methods and means are successful. All success is obtained by the permission of Allah alone"
Getting that sinking feeling on reading published studies
Keith S. Taber
this is like finding that, after a period of watering plant A, it is taller than plant B – when you did not think to check how tall the two plants were before you started watering plant A
Research on prelabs
I was looking for studies which explored the effectiveness of 'prelabs', activities which students are given before entering the laboratory to make sure they are prepared for practical work, and can therefore use their time effectively in the lab. There is much research suggesting that students often learn little from science practical work, in part because of cognitive overload – that is, learners can be so occupied with dealing with the apparatus and materials they have little capacity left to think about the purpose and significance of the work. 1
Okay, so is THIS the pipette? (Image by PublicDomainPictures from Pixabay)
Approaching a practical work session having already spent time engaging with its purpose and associated theories/models, and already having become familiar with the processes to be followed, should mean students enter the laboratory much better prepared to use their time efficiently, and much better informed to reflect on the wider theoretical context of the work.
I found a Swedish paper (Winberg & Berg, 2007) reporting a pair of studies that tested this idea by using a simulation as a prelab activity for undergraduates about to engage with an acid-base titration. The researchers tested this innovation by comparisons between students who completed the prelab before the titration, and those who did not.
The work used two basic measures:
types (sophistication) of questions asked by students during the lab. session
elicitation of knowledge in interviews after the laboratory activity
The authors found some differences (between those who had completed the prelab and those that had not) in the sophistication of the questions students asked, and in the quality of the knowledge elicited. They used inferential statistics to suggest at least some of the differences found were statistically significant. From my reading of the paper, these claims were not justified.
A peer reviewed journal (no, really, this time)
This is a paper in a well respected journal (not one of the predatory journals I have often discussed on this site). The Journal of Research in Science Teaching is published by Wiley (a major respected publisher of academic material) and is the official journal of NARST (which used to stand for the National Association for Research in Science Teaching – where 'national' referred to the USA 2). This is a journal that does take peer review very seriously.
The paper is well-written and well-structured. Winberg and Berg set out a conceptual framework for the research that includes a discussion of previous relevant studies. They adopt a theoretical framework based on the Perry's model of intellectual development (Taber, 2020). There is considerable detail of how data was collected and analysed. This account is well-argued. (But, you, dear reader, can surely sense a 'but' coming.)
Experimental research into experimental work?
The authors do not seem to explicitly describe their research as an experiment as such (as opposed to adopting some other kind of research strategy such as survey or case study), but the word 'experiment' and variations of it appear in the paper.
For one thing, the authors refer to students' practical work as being experiments,
"Laboratory exercises, especially in higher education contexts, often involve training in several different manipulative skills as well as a high information flow, such as from manuals, instructors, output from the experimental equipment, and so forth. If students do not have prior experiences that help them to sort out significant information or reduce the cognitive effort required to understand what is happening in the experiment, they tend to rely on working strategies that help them simply to cope with the situation; for example, focusing only on issues that are of immediate importance to obtain data for later analysis and reflective thought…"
Winberg & Berg, 2007
Now, some student practical work is experimental, where a student is actively looking to see what happens when they manipulate some variable to test a hypothesis. This type of practical work is sometimes labelled enquiry (or inquiry in US spelling). But a lot of school and university laboratory work, however, is undertaken to learn techniques, or (probably more often) to support the learning of taught theory – where it is usually important the learners know what is meant to happen before they begin the laboratory activity.
Winberg and Berg refer to the 'laboratory exercise' as 'the experiment' as though any laboratory work counts as an experiment. In Winberg and Berg's research, students were asked about their "own [titration] experiment", despite the prelab material involving a simulation of the titration process, in advance of which "the theoretical concepts, ideas, and procedures addressed in the simulation exercise had been treated mainly quantitatively during the preceding 1-week instructional sequence". So, the laboratory titration exercise does not seem to be an experiment in the scientific sense of the term.
School children commonly describe all practical work in the lab as 'doing experiments'. It cannot help students learn what an experiment really is when the word 'experiment' has two quite distinct meanings in the science classroom:
experiment(technical) = an empirical test of a hypothesis involving the careful control of variables and observation of the effect on a specified (hypothetised as) dependent variable of changing the variable specified as the independent variable
experiment(casual) = absolutely any practical activity carried out with laboratory equipment
We might describe this second meaning as an alternative conception of 'experiment', a way of understanding that is inconsistent with the scientific meaning. (Just as there are common alternative conceptions of other 'nature of science' concepts such as 'theory').
I would imagine Winberg and Berg were well aware of what an experiment is, although their casual use of language might suggest a lack of rigour in thinking with the term. They refer to having "both control and experiment groups" in their studies, and refer to "the experimental chronology" of their research design. So, they certainly seem to think of their work as a kind of experiment.
Experimental design
In a true experiment, a sample is randomly drawn from a population of interest (say, first year undergraduate chemistry students; or, perhaps, first year undergraduate chemistry students attending Swedish Universities, or… 3) and assigned randomly to the conditions being compared. Providing a genuine form of random assignment is used, then inferential statistical tests can guide on whether any differences found between groups at the end of an experiment should be considered statistically significant. 4
"Statistics can only indicate how likely a measured result would occur by chance (as randomisation of units of analysis to different treatments can only make uneven group composition unlikely, not impossible)…Randomisation cannot ensure equivalence between groups (even if it makes any imbalance just as likely to advantage either condition)"
Inferential statistics can be used to test for statistical significance in experiments – as long as the 'units of analysis' (e.g., students) are randomly assigned to the experimental and control conditions. (Figure from Taber, 2019)
That is, if the are difference that the stats. tests suggests are very unlikely to happen by chance, then they are very unlikely to be due to an initial difference between the groups in the two conditions as long as the groups were the result of random assignment. But that is a very important proviso.
There are two aspects to this need for randomisation:
to be able to suggest any differences found reflect the effects of the intervention, then there should be random assignment to the two (or more) conditions
to be able to suggest the results reflect what would probably would be found in a wider population, the sample should be randomly selected from the population of interest 3
Studies in education seldom meet the requirements for being true experiments (Figure from Taber, 2019)
In education, it is not always possible to use random assignment, so true experiments are then not possible. However, so-called 'quasi-experiments' may be possible where differences between the outcomes in different conditions may be understood as informative, as long as there is good reason to believe that even without random assignment, the groups assigned to the different conditions are equivalent.
In this specific research, that would mean having good reason to believe that without the intervention (the prelab):
students in both groups would have asked overall equivalent (in terms of the analysis undertaken in this study) questions in the lab.;
students in both groups would have been judged as displaying overall equivalent subject knowledge.
Often in research where a true experiment is not possible some kind of pre-testing is used to make a case for equivalence between groups.
Two control groups that were out of control
In Winberg and Berg's research there were two studies where comparisons were made between 'experimental' and 'control' conditions
Study
Experimental
Control
Study 1
n=78: first-year students, following completion of their first chemistry course in 2001
n=97: students who had been interviewed by the researchers during the same course in the previous year
Study 2
n=21 (of 58 in cohort)
n=37 (of 58 in same cohort)
In the first study, a comparison was made between the cohort where the innovation was introduced and a cohort from the previous year. All other things being equal, it seems likely these two cohorts were fairly similar. But in education all thing are seldom equal, so there is no assurance they were similar enough to be considered equivalent.
In the second study
"Students were divided into treatment (n = 21) and control (n = 37) groups. Distribution of students between the treatment and control groups was not controlled by the researchers".
Winberg & Berg, 2007
So, some factor(s) external to the researchers divided the cohort into two groups – and the reader is told nothing about the basis for this, nor even if the two groups were assigned to the treatments randomly.5 The authors report that the cohort "comprised prospective molecular biologists (31%), biologists (51%), geologists (7%), and students who did not follow any specific program (11%)", and so it is possible the division into two uneven sized groups was based on timetabling constraints with students attending chemistry labs sessions according to their availability based on specialism. But that is just a guess. (It is usually better when the reader of a research report is not left to speculate about procedures and constraints.)
What is important for a reader to note is that in these studies:
the researchers were not able to assign learners to conditions randomly;
nor were the researchers able to offer any evidence of equivalence between groups (such as near identical pre-test scores);
so, the requirements for inferring significance from statistical tests were not met;
so, claims in the paper about finding statistically significant differences between conditions cannot therefore be justified given the research design;
and therefore the conclusions presented in the paper are strictly not valid.
If students are not randomly assigned to conditions, then any statistically unlikely difference found at the end of an experiment cannot be assumed to be likely to be due to intervention, rather than some systematic initial difference between the groups. (Figure adapted from Taber, 2019)
This is a shame, because this is in many ways an interesting paper, and much thought and care seems to have been taken about the collection and analysis of meaningful data. Yet, drawing conclusions from statistical tests comparing groups that might never have been similar in the first case is like finding that careful use of a vernier scale shows that after a period of watering plant A, plant A is taller than plant B – having been very careful to make sure plant A was watered regularly with carefully controlled volumes, while plant B was not watered at all – when you did not think to check how tall the two plants were before you started watering plant A.
In such a scenario we might be tempted to assume plant A has actually become taller because it had been watered; but that is just applying what we had conjectured should be the case, and we would be mistaking our expectations for experimental evidence.
Work cited:
Taber, K. S. (2013). Non-random thoughts about research. Chemistry Education Research and Practice, 14(4), 359-362. doi:10.1039/c3rp90009f
Winberg, T. M., & Berg, C. A. R. (2007). Students' cognitive focus during a chemistry laboratory exercise: Effects of a computer-simulated prelab. Journal of Research in Science Teaching, 44(8), 1108-1133. https://doi.org/https://doi.org/10.1002/tea.20217
Notes:
1 The part of the brain where we can consciously mentipulate ideas is called the working memory (WM). Research suggests that WM has a very limited capacity in the sense that people can only hold in mind a very small number of different things at once. (These 'things' however are somewhat subjective – a complex idea that is treated as a single 'thing' in the WM of an expert can overload a novice.) This limit to ~WM is considered to be one of the most substantial constraints on effective classroom learning. This is also, then, one of the key research findings informing the design of effective teaching.
2 The organisation has seemingly spotted that the USA is only one part of the world, and now describes itself as a global organisation for improving science education through research.
3 There is no reason why an experiment cannot be carried out on a very specific population, such as first year undergraduate chemistry students attending a specific Swedish University such a, say, Umea ̊ University. However, if researchers intend their study to have results generalisable beyond their specific research contexts (say, to first year undergraduate chemistry students attending any Swedish University) then it is important to have a representative sample of that population.
4 It might be assumed that scientists, and researchers know what is meant by random, and how to undertake random assignment. Sadly, the literature suggests that in practice the term 'randomly' is sometimes used in research reports to mean something like 'arbitrarily' (Taber, 2013), which fills short of being random.
5 Arguably, even if the two groups were assigned randomly, there is only one 'unit of analysis' in each condition, as they were assigned as groups. That is, for statistical purposes, the two groups have size n=1 and n=1, which would not allow statistical significance to be found: e.g, see 'Quasi-experiment or crazy experiment?'
One of the most fundamental ideas in physics, surely taught in every secondary school science curriculum around the world, is also the focus of one of the most common alternative conceptions documented in science education. Inertia. Much research in the latter part of the twentieth century has detailed how most people have great trouble with this very simple idea.
But that would likely not have surprised the nineteenth century French physicist (and mathematician and philosopher) Henri Poincaré in the least. Over a century ago he had this to say about the subject of Newton's first law, inertia,
"The principle of inertia. A body acted on by no force can only move uniformly in a straight line.
Is this a truth imposed a priori upon the mind? If it were so, how could the Greeks have failed to recognise it? How could they have believed that motion stops when the cause which gave birth to it ceases? Or again that every body if nothing prevents, will move in a circle, the noblest of motions?
If it is said that the velocity of a body can not change if there is no reason for it to change, could it not be maintained just as well that the position of this body can not change, or that the curvature of its trajectory can not change, if no external cause intervenes to modify them?
Is the principle of inertia, which is not an a priori truth, therefore an experimental fact? But has any one ever experimented on bodies withdrawn from the action of every force? and, if so, how was it known that these bodies were subjected to no force?"
Poincaré, 1902/1913/2015
There is quite a lot going on in that quote, so it is worth breaking it down.
The principle of inertia
"The principle of inertia. A body acted on by no force can only move uniformly in a straight line."
Poincaré, 1902/1913/2015
We might today choose to phrase this differently – at least in teaching. Perhaps along the lines that
a body remains at rest, or moving with uniform motion, unless it is acted upon by a net (overall) force
That's a pretty simple idea.
If you want something that is stationary to start moving, you need to apply a force to it. Otherwise it will remain stationary. And:
If you want something that is moving with constant velocity to slow down (decelerate), speed up (accelerate), or change direction, you need to apply a force to it. Otherwise it will carry on moving in the same direction at the same speed.
A simple idea, but one which most people struggle with!
It is worth noting that Poincaré's formulation seems simpler than the versions more commonly presented in school today. He does not make reference to a body at rest; and we might detect a potential ambiguity in what is meant by "can only move uniformly in a straight line".
Is the emphasis:
can only move uniformly in a straight line:
i.e., 〈 can only 〉 〈 move uniformly in a straight line 〉, or
can only move uniformly in a straight line:
i.e., 〈 can only move 〉 〈 uniformly in a straight line 〉
That is, must such a body "move uniformly in a straight line" or must such a body, if moving, "move uniformly in a straight line"? A body acted on by no force may be stationary.
Perhaps this is less ambiguous in the original French? But I suspect that, as a physicist, Poincairé did not, particularly, see the body at rest as being much of a special case.
To most people the distinction between something stationary and something moving is very salient (evolution has prepared us to notice movement). But to a physicist the more important distinction is between any body at constant velocity, and one accelerating* – and a body not moving has constant velocity (of 0 ms-1!)
*and for a physicist accelerating usually includes decelerating, as that is just acceleration with a negative vale, or indeed positive acceleration in a different direction. These 'simplifications' seem very neat – to the initiated (but perhaps not to novices!)
A historical scientific conception
Poincaré then asks:
Is this a truth imposed a priori upon the mind? If it were so, how could the Greeks have failed to recognise it? How could they have believed that motion stops when the cause which gave birth to it ceases?"
Poincaré, 1902/1913/2015
Poincairé asks a rhetorical question: "Is this a truth imposed a priori upon the mind?" Rhetorical, as he immediately suggests the answer. No, it cannot be.
Science is very much an empirical endeavour. The world is investigated by observation, indeed often observation of the effects of interventions (i.e., experiments).
In this way, it diverges from a rationalist approach to understanding the world based on reflection and reasoning that occurs without seeking empirical evidence.
An aside on simulations and perpetual change
Yet, even empirical science depends on some (a priori) metaphysical commitments that cannot themselves be demonstrated by scientific observation (e.g., Taber, 2013). As one example, the famous 'brain in a vat' scenario (that informed films such as The Matrix) asks how we could know that we really experience an external world rather than a very elaborate virtual reality fed directly into our central nervous system (assuming we have such a thing!) 1
Science only makes sense if we believe that the world we experience is an objective reality originating outside our own minds (Image by Gerd Altmann from Pixabay)
Despite this, scientists operate on the assumption this is a physical world (that we all experience), and one that has a certain degree of stability and consistency. 2 The natural scientist has to assume this is not a capricious universe if science (a search for the underlying order of the world) is to make sense!
It may seem this (that we live in is an objective physical world that has a certain degree of stability and consistency) is obviously the case, as our observations of the world find this stability. But not really: rather, we impose an assumption of an underlying stability, and interpret accordingly. The sun 'rises' every day. (We see stability.) But the amount of daylight changes each day. (We observe change, but assume, and look for, and posit, some underlying stability to explain this.)
Continental drift, new comets, evolution of new species and extinction of others, supernovae, the appearance of HIV and COVID, increasing IQ (disguised by periodically renormalising scoring), climate change, the expanding universe, plant growth, senile dementia, rotting fruit, printers running out of ink, lovers falling out of love, et cetera,…are all assumed to be (and subsequently found to be) explainable in terms of underlying stable and consistent features of the world!
But it would be possible to consider nothing stays the same, and seek to explain away any apparent examples of stability!
Parmenides thought change is impossible
Heraclitus though everything was in flux
An a priori?
So Poincaré was asking if the principle of is inertia was something that would appear to us as a given; is inertia something that seems a necessary and obvious feature of the world (which it probably does to most physicists – but that is after years of indoctrination into that perspective).
But, Poincaré was pointing out, we know that for centuries people did not think that objects not subject any force would continue to move with constant velocity.
There were (considered to be) certain natural motions, and these had a teleological aspect. So, heavy objects, that were considered mainly earth naturally fell down to their natural place on the ground. 3 Once there, mission accomplished (so to speak), they would stop moving. No further explanation was considered necessary.
Violent motions were (considered to be) different as they needed an active cause – such as a javelin moving through the air because someone had thrown it. Yet, clearly (it was believed), the athlete could only impart a finite motion to the javelin, which it would soon exhaust, so the javelin would (naturally) stop soon enough.
Today, such ideas are seen as alternative conceptions (misconceptions), but for hundreds of years these ideas were largely taken as self-evident and secure principles describing aspects of the world. The idea that the javelin might carry on moving for ever if it was 'left to its own devices' seemed absurd. (And to most people today who are not physicists or science teachers, it probably still does!)
An interesting question is if, and if so, to what extent, the people who become physicists and physics teachers start out with intuitions more aligned with the principles of physics than most of their classmates.
"Assuming that there is significant variation in the extent to which our intuitive physics matches what we are taught in school, I would expect that most physics teachers are among those to whom the subject seemed logical and made good sense when they were students. I have no evidence for this, but it just seems natural that these students would have enjoyed and continued with the subject.
If I am right about this intuition, then this may be another reason why physics is so hard for some of our students. Not only do they have to struggle with subject matter that seems counterintuitive, but the very people who are charged with helping them may be those who instinctively think most differently from the way in which they do."
Taber, 2004, p.124
Another historical scientific conception
And Poincaré went on:
"Or again that every body if nothing prevents, will move in a circle, the noblest of motions?"
Poincaré, 1902/1913/2015
It was also long thought that in the heavens bodies naturally moved spontaneously in circles – a circle being a perfect shape, and the heavens being a perfect place.
Orbital motion – once viewed to be natural (i.e., not requiring any further explanation) and circular in 'the heavens'. (Image by WikiImages from Pixabay: Body sizes and separations not to the same scale!)
It is common for people to feel that what seems natural does not need further explanation (Watts & Taber, 1996) – even though most of what we consider natural is likely just familiarity with common phenomena. We start noticing how the floor arrests the motion of falling objects very young in life, so by the time we have language to help reflect on this, we simply explain this as motion stopping because the floor was in the way! Similarly, reaction forces are not obvious when an object rests on another – a desk, a shelf, etc – as the object cannot fall 'because it is supported'.
Again, we (sic, wethe initiated) now think that without an acting centripetal force, an orbiting body would move off at a tangent – but that would have seemed pretty bizarre for much of European history.
The idea that bodies moved in circles (as the fixed stars seemed to do) was maintained despite extensive observational evidence collected over centuries that the planets appeared to do something quite different. Today Kepler's laws are taught in physics, including that the solar system's orbiting bodies move (almost) in ellipses. ('Almost', as they bodies perturb each other a little.)
But when Kepler tried to fit observations to theory by adopting Copernicus's 'heliocentric' model of the Earth and planets orbiting the Sun (Earth and other planets, we would say), he still struggled to make progress for a considerable time because of an unquestioned assumption that the planetary motions had to be circular, or some combination of multiple circles.
Learners' alternative conceptions
These historical ideas are of more than historical interest. Many people, research suggests most people, today share similar intuitions.
Objects will naturally come to a stop when they have used up their imparted motion without the need for any forces to act.
Something that falls to the floor does not need a force to act on it to stop it moving, as the ground is in its way.
Moons and planets continue in orbits because there is no overall force acting on them.
The vast majority of learners some to school science holding versions of such alternative conceptions.
The majority of learners also leave school holding versions of such alternative conceptions – even if some of them have mastered the ability to usually respond to physics test questions as if they accepted a different worldview.
The idea that objects soon stop moving once the applied force ceases to act may be contrary to physics, but it is not, of course, contrary to common experience – at least not contrary to common experience as most people perceive it.
Metaphysical principles
Poincaré recognised this.
"If it is said that the velocity of a body can not change if there is no reason for it to change [i.e. the principle of inertia],
could it not be maintained just as well that
the position of this body can not change, or
that the curvature of its trajectorycan not change,
if no external cause intervenes to modify them?"
Poincaré, 1902/1913/2015 (emphasis added)
After all, as Poincairé pointed out, there seems no reason, a priori, that is intuitively, to assume the world must work according to the principle of inertia (though some physicists and science teachers whom have been indoctrinated over many years may have come to think otherwise – of course after indoctrination is not a priori!), rather than assuming, say, that force must act for movement to occur and/or that force must act to change an orbit.
Science as an empirical enterprise
Science teachers might reply, that our initial intuitions are not the point, because myriad empirical tests have demonstrated the principle of inertia. But Poincairé suggested this was strictly not so,
"Is the principle of inertia, which is not an a priori truth, therefore an experimental fact? But has any one ever experimented on bodies withdrawn from the action of every force? and, if so, how was it known that these bodies were subjected to no force?"
Poincaré, 1902/1913/2015
For example, if we accept the ideas of universal gravitation, than anywhere in the universe a body will be subject to gravitational attractions (that is, forces). A body could only be completely free of this by being in a universe of its own with no other gravitating bodies. Then we might think we could test, in principle at least, whether the body "acted on by no force can only move uniformly in a straight line".
Well, apart from a couple of small difficulties. There would be no observers in this universe to see, as we have excluded all other massive bodies. And if this was the only body there, it would be the only frame of reference available – a frame of reference in which it was always stationary. It would always be at the centre of, and indeed would be the extent of, its universe.
Poincaré and pedagogic awareness
Poincaré was certainly not denying the principle of inertia so fundamental to mechanics. But he was showing that he appreciated that a simple principle which seems (comes to seem?) so basic and obvious to the inducted physics expert:
was hard won in the history of science
in not 'given' in intuition
is not the only possible basic principle on which a mechanics (in some other universe) could be based
is contrary to immediate experience (that is, to those who have not been indoctrinated to 'see' resistive forces sch as friction acting everywhere)
could never be entirely demonstrated in a pure form, but rather must be inferred from experimental tests of more complex situations where we will only deduce the principle of inertia if we assume a range of other principles (about the action of gravitational fields, air resistance, etc.)
Poincaré may have been seen as one of the great physicists of his time, but his own expertise certainly did not him appreciating the challenges facing the learner of physics, or indeed the teacher of physics.
Work cited:
Taber, K. S. (2004) Intuitive physics: but whose intuition are we talking about?, Physics Education, 39 (2), pp.123-124.
Watts, M. and Taber, K. S. (1996) An explanatory gestalt of essence: students' conceptions of the 'natural' in physical phenomena, International Journal of Science Education, 18 (8), pp.939-954.
Notes
1 With current human technology we cannot achieve this – even the best virtual worlds clearly do not yet come close to the real one! But that argument falls away if 'the real' world we experience is such a virtual reality created by very advanced technology, and what we think of as virtual worlds are low definition simulations being created within that! (After all, when people saw the first jumpy black-and-white movies, they then came out from the cinema into a colourful, smooth and high definition world.) If you have ever awaken from a dream, only to later realise you are still asleep, and had been dreaming of being asleep in the dream, then you may appreciate how such nesting of worlds could work.
Probably no one actually believes they are a brain in a vat, but how would we know. There is an argument that
1) the evolution of complex life is a very slow process that requires a complex ecosystem, but
2) once humans (or indeed non-humans) have the technology to create convincing virtual worlds this can be done very much more quickly, and with much less resource [i.e., than the evolution of the physical world which within which the programmers of the simulations themselves live]. So,
3) if we are living in a phase of the universe where such technology has been achieved, then we would expect there to be a great many more such virtual worlds than planets inhabited by life forms with the level of self-consciousness to think about whether they are in a simulation.4 So,
4) [if we are living in a phase of the universe where such technology has been achieved] we would be much more likely to be living in one of these worlds (a character in a very complex simulation) than an actual organic being. 5
2 That is, not a simulation where an adolescent programmer is going to suddenly increase gravity or add a new fundamental force just to make things more interesting.
3 Everything on earth was considered to be made up of different proportions of the four elements, which in terms of increasing rarity were earth, water, air and fire. The rocks of the earth were predominately the element earth – and objects that were mainly earth fell to their natural place. (Rarity in this context means the inverse of density, not scarcity.)
4 When I was a child (perhaps in part because I think I started Sunday School before I could start 'proper' school), I used to muse about God being able to create everything, and being omniscient – although I am pretty sure I did not use that term! It seemed to me (and, sensibly, I do not think I shared this at Sunday School) that if God knew everything and was infallible, then he did not need to actually create the world as a physical universe, but rather just think what would happen. For God, that would work just as well, as a perfect mind could imagine things exactly as they would be in exquisite detail and with absolute precision. So, I thought I might just be an aspect of the mind of God – so part of a simulation in effect. This was a comforting rather than worrying thought – surely there is no safer place to be than in the mind of God?
Sadly, I grew to be much less sure of God (the creation seems just as incredible – in the literal sense – either way), but still think that, for God, thinking it would be as good as (if not the same as) making it. I suspect some theologians would not entirely dismiss this.
If I am just a character in someone's simulation, I'd rather it was that of a supreme being than some alien adolescent likely to abandon my world at the first sign of romantic interest from a passing conspecific.
5 Unless we assume a dystopian Matrix like simulation, the technology has to be able to create characters (sub-routines?) with self-awareness – which goes some way beyond just a convincing simulation, as it also requires components complex enough to be convinced about their own existence, as well as the reality of the wider simulation!
