Category: science in the media

How much damage can a couple of molecules do?

Just how dangerous is Novichok?

Keith S. Taber

"We are only talking about molecules here…

There might be a couple of molecules left in the Salisbury area. . ."

Expert interviewed on national news

The subject of chemical weapons is not to be taken lightly, and is currently in the news in relation to the Russian invasion of Ukraine, and the concern that the limited progress made by the Russian invaders may lead to the use of chemical or biological weapons to supplement the deadly enough effects of projectiles and explosives.

Organophosphorus nerve agents (OPNA) were used in Syria in 2013 (Pita, & Domingo, 2014), and the Russians have used such nerve agents in illicit activities – as in the case of the poisoning of Sergey Skripal and his daughter Yulia in Salisbury. Skripal had been a Russian military intelligence officer who had acted for the British (i.e., as a double agent), and was convicted of treason – but later came to the UK in a prisoner swap and settled in Salisbury (renown among Russian secret agents for its cathedral). 1

Salisbury, England – a town that featured in the news when it was the site of a Russian 'hit' on a former spy (Image by falco from Pixabay )

These substances are very nasty,

OPNAs are odorless and colorless [and] act by blocking the binding site of acetylcholinesterase, inhibiting the breakdown of acetylcholine… The resulting buildup of acetylcholine leads to the inhibition of neural communication to muscles and glands and can lead to increased saliva and tear production, diarrhea, vomiting, muscle tremors, confusion, paralysis and even death

Kammer, et al., 2019, p.119

So, a substance that occurs normally in cells, but is kept in check by an enzyme that breaks it down, starts to accumulate because the enzyme is inactivated when molecules of the toxin bind with the enzyme molecules stopping them binding with acetylcholine molecules. Enzymes are protein based molecules which rely for their activity on complex shapes (as discussed in 'How is a well-planned curriculum like a protein?' .)

Acetylcholine is a neurotransmitter. It allows signals to pass across synapses. It is important then that acetylcholine concentrations are controlled for nerves to function (Image source: Wikipedia).

Acetylcholinesterase is a protein based enzyme that has an active site (red) that can bind and break up acetylcholine molecules (which takes about 80 microseconds per molecule). The neurotransmitter molecule is broken down into two precursors that are then available to be synthesised back into acetylcholine when appropriate. 2

Toxins (e.g., green, blue) that bind to the enzyme's active site block it from breaking down acetylcholine.

(Image source: RCSB Protein Data Bank)

A need to clear up after the release of chemical agents

The effects of these agents can be horrific – but, so of course, can the effects of 'conventional' weapons on those subjected to aggression. One reason that chemical and biological weapons are banned from use in war is their uncontrollable nature – once an agent is released in an environment it may remain active for some time – and so hurt or kill civilians or even personnel from the side using those weapons if they move into the attacked areas. The gases used in the 1912-1918 'world' war, were sometimes blown back towards those using them when the wind changed direction.

Image by Eugen Visan from Pixabay 

This is why, when small amounts of nerve agents were used in the U.K. by covert Russian agents to attack their targets, there was so much care put into tracing and decontaminating any residues in the environment. This is a specialised task, and it is right that the public are warned to keep clear of areas of suspected contamination. Very small quantities of some agents can be very harmful – depending upon what we mean by such relative terms as 'small'. Indeed, two police officers sent to the scene of the crime became ill. But what does 'very small quantities' mean in terms of molecules?

A recent posting discussed the plot of a Blakes7 television show episode where a weapon capable of destroying whole planets incorporated eight neutrons as a core component. This seemed ridiculous: how much damage can eight neutrons do?

But, I also pointed out that, sadly, not all those who watched this programme would find such a claim as comical as I did. Presumably, the train of thought suggested by the plot was that a weapon based on eight neutrons is a lot more scary than a single neutron design, and neutrons are found in super-dense neutron stars (which would instantly crush anyone getting too near), so they are clearly very dangerous entities!

A common enough misconception

This type of thinking reflects a common learning difficulty. Quanticles such as atoms, atomic nuclei, neutrons and the like are tiny. Not tiny like specs of dust or grains of salt, but tiny on a scale where specs of dust and grains of salt themselves seem gigantic. The scales involves in considering electronic charge (i.e., 10-19C) or neutron mass (10-27 kg) can reasonably be said to be unimaginatively small – no one can readily visualise the shift in scale going from the familiar scale of objects we normally experience as small (e.g., salt grains), to the scale of individual molecules or subatomic particles.

People therefore commonly form alternative conceptions of these types of entities (atoms, electrons, etc.) being too small to see, but yet not being so far beyond reach. It perhaps does not help that it is sometimes said that atoms can now be 'seen' with the most powerful microscopes. The instruments concerned are microscopes only by analogy with familiar optical microscopes, and they produce images, but these are more like computer simulations than magnified images seen through the light microscope. 3

It is this type of difficulty which allows scriptwriters to refer to eight neutrons as being of some significance without expecting the audience to simply laugh at the suggestion (even if some of us do).

An expert opinion

Although television viewers might have trouble grasping the insignificance of a handful of neutrons (or atoms or molecules), one would expect experts to be very clear about the vast difference in scale between us (people for example) and them (nanoscopic entities of the molecular realm). Yet experts may sometimes be stretched beyond their expertise without themselves apparently being aware of this – as when a highly qualified and experienced medical expert agreed with an attorney that the brain sends out signals to the body faster than the speed of light. If a scientific expert in a high profile murder trial can confidently make statements that are scientifically ridiculous then this underlines just how challenging some key scientific ideas are.

For any of us, knowing what we do not know, recognising when we are moving outside out of areas where we have a good understanding, is challenging. Part of the reason that student alternative conceptions are so relevant to science learning is that a person's misunderstanding can seem subjectively to be just as well supported, sensible, coherent and reasonable as a correct understanding. Where a teacher themself has an alternative conception (which sometimes happens, of course) they can teach this with as much enthusiasm and confidence as anything they understand canonically. Expertise always has limitations.

A chemical weapons expert

I therefore should not have been as surprised as I was when I heard a news broadcast featuring an expert who was considered to know about chemical weapons refer to the potential danger of "a couple of molecules". This was in relation to the poisoning by Russian agents of the Salisbury residents,

"During an interview on a BBC Radio 4 news programme (July 5th, 2018), Hamish de Bretton-Gordon, who brands himself as one of the world's leading chemical weapons experts, warned listeners that there may be risks to the public due to residue from the original incident in the area. Whilst that may have been the case, his suggestion that "we are only talking about molecules here. . .There might be a couple of molecules left in the Salisbury area. . ." seemed to suggest that even someone presented to the public as a chemistry expert might completely fail to appreciate the submicroscopic scale of individual molecules in relation to the macroscopic scale of a human being."

Taber, 2019, p.130
Chemical weapons expert ≠ chemistry expert

Now Colonel de Bretton-Gordon is a visiting fellow at  Magdalene College Cambridge, and the College website describes him as "a world-leading expert in Chemical and Biological weapons". I am sure he is, and I would not seek to underplay the importance of decontamination after the use of such agents; but if someone who has such expertise would assume that a couple of molecules of any substance posed a realistic threat to a human being with its something like 30 000 000 000 000 cells, each containing something like 40 000 000 molecules of protein (to just refer to one class of cellular components), then it just underlines how difficult it is to appreciate the gulf in scale between molecules and men.

Regarding samples of nerve agents, they may be deadly even in small quantities, but that still means a lot of molecules.

Novichok cocktails

The attacks in Salisbury (from which the intended victims recovered, but another person died in nearby Amesbury apparently having come into contact with material assumed to have been discarded by the criminals), were reported to have used 'Novichok', a label given to group of compounds.

"Based on analyses carried out by the British "Defence Science and Technology Laboratory" in Porton Down it was concluded that the Skripals were poisoned by a nerve agent of the so-called Novichok group. Novichok … is the name of a group of nerve agents developed and produced by Russia in the last stage of the Cold War."

Carlsen, 2019, p.1

Testing of toxins is often based on the LD50 – which means finding the dose that has an even chance of being lethal. This is not an actual amount, as clearly the amount of material that is needed to kill a large adult will be more than that to kill a small child, but the amount of the toxin needed per unit mass of victim. Although no doubt these chemicals have been directly tested on some poor test specimens of non-consenting small mammals, such information is not in the public domain.

Indeed, being based on state secrets, there is limited public data on Novichok and related agents. Carlsen (2019) estimates the LD50 for oral administration of 9 compounds in the Novichok group and some closely related agents to vary between 0.1 to 96.16 mg/kg.

Carlsen suggest the most toxic of these compounds is one known as VX. VX was actually first developed by British Scientists, although almost equivalent nerve agents were later developed elsewhere, including Russia.

'Chemical structures of V-agents.'
(Figure 2 from Nepovimova & Kuca, 2018 – subject to http://creativecommons.org/licenses/BY-NC-ND/4.0/)
n.b. This figure shows more than a couple of molecules of nerve agent – so might this be a lethal dose?

Carlsen then argues that the actual compounds in Novachok are probably less toxic than XV, which might explain…

"…why did the Skripals not die following expose to such high potent agents; just compare to the killing of Kim Jong-nam on February 13, 2017 in Kuala Lumpur International Airport, where he was attacked by the highly toxic VX, and died shortly after."

Carlsen, 2019, p1

So, for the most sensitive agent, known as XV (LD50 c. 0.1 mg/kg), a person of 50 kg mass would it is estimated have a 50% chance of being killed by an oral dose of 0.1 x 50 mg. That is 5 mg or 0.005 g by mouth. A single drop of water is said to have a volume of about 0.05 ml, and so a mass of about 0.05 g. So, a tenth of a drop of this toxin can kill. That is a very small amount. So, if as little as 0.005 g of a nerve agent will potentially kill you then that is clearly a very toxic substance.

The molecular structure of XV is given in the figure above taken from Nepovimova and Kuca (2018). These three structures shown appear to be isomeric – that is the three molecules are structural isomers. They would have the same empirical formula (and the same molecular mass).

Chemical shorthand

This type of structural formula is often used for complex organic molecules as it is easy for experts to read. It is one of many special types of representation used in chemistry. It is based on the assumption that most organic compounds can be understood as if substituted hydrocarbons. (They may or may not be derived that way – this is jut a formalism used as a thinking tool.) Hydrocarbons comprise chains of carbon atomic cores bonded to each other, and with their other valencies 'satisfied' by being bonded to hydrogen atomic cores. These compounds can easily be represented by lines where each line shows the bond between two carbon atomic cores. The hydrogen centres are not shown at all, but are implicit in the figure (they must be there to 'satisfy' the rules of valency – i.e., carbon centres in a stable structures nearly always have four bonds ).

Anything other than carbon and hydrogen is shown with elemental symbols, and in most organic compounds these other atomic centres take up on a minority of positions in the structure. So, for compounds, such as the 'VX' compounds, these kinds of structural representations are a kind of hybrid, with some atomic centres shown by their elemental symbols – but others having to be inferred.

From the point of view of the novice learner, this form of abstract representation is challenging as carbon and hydrogen centres need to be actively read into the structure (whereas an expert has learnt to do this automatically). But for the expert this type of representation is useful as complex organic molecules can contain hundreds or thousands of atomic centres (e.g., the acetylcholinesterase molecule, as represented above) and structural formulae that show all the atomic centres with elemental symbols would get very crowded.

So, below I have annotated the first version of XV:

The VX compound seems to have a molecular mass of 267

This makes the figure much more busy, but helps me count up the numbers of different types of atomic centres present and therefore work out the molecular mass – which, if I had not made a mistake, is 267. I am working here with the nearest whole numbers, so not being very precise, but this is good enough for my present purposes. That means that the molecule has a mass of 267 atomic mass units, and so (by one of the most powerful 'tricks' in chemistry) a mole of this compound, the actual substance, would have a mass of 267g.

The trick is that chemists have chosen their conversion factor between molecules and moles, the Avogadro constant of c. 6.02 x 1023, such that adding up atomic masses in a molecule gives a number that directly scales to grammes for the macroscopic quantity of choice: the mole. 5

So, if one had 267 g of this nerve agent, that would mean approximately 6.02 x 1023 molecules. Of course here we are talking about a much smaller amount – just 0.005 g (0.005/267, about 0.000 02 moles) – and so many fewer molecules. Indeed we can easily work out 0.005 g contains something like

(0.005 / 267) x 6.02 x 1o23 = 11 273 408 239 700 374 000 = 1×1019 (1 s.f.)

That is about

10 000 000 000 000 000 000 molecules

So, because of the vast gulf in scale between the amount of material we can readily see and manipulate, and the individual quanticle such as a molecule, even when we are talking about a tiny amount of material, a tenth of a drop, this still represent a very, very large number of molecules. This is something chemistry experts are very aware of, but most people (even experts in related fields) may not fully appreciate.

The calculation here is approximate, and based on various estimates and assumptions. It may typically take about 10 000 000 000 000 000 000 molecules of the most toxic Novichok-like agent to be likely to kill someone – or this estimate could be seriously wrong. Perhaps it takes a lot more, or perhaps many fewer, molecules than this.

But even if this estimate is out by several orders of magnitude and it 'only' takes a few thousand million million molecules of XV for a potential lethal dose, that can in no way be reasonably described as "a couple of molecules".

It takes very special equipment to detect individual quanticles. The human retina is in its own way very sophisticated, and comes quite close to being able to detect individual photons – but that is pretty exceptional. As a rule of thumb, when anyone tells us that a few molecules or a few atoms or a few ions or a few electrons or a few neutrons or a few gamma rays or… can produce any macroscopic effect (that we can see, feel, or notice) we should be VERY skeptical.

Work cited:
Notes:

1 Two men claiming to be the suspects whose photographs had been circulated by the British Police, and claimed by the authorities here to be Russian military intelligence officers, appeared on Russian television to explain they were tourists who had visited Salisbury sightseeing because of the Cathedral.

2 According to the RCSB Protein Data Bank website

"Acetylcholinesterase is found in the synapse between nerve cells and muscle cells. It waits patiently and springs into action soon after a signal is passed, breaking down the acetylcholine into its two component parts, acetic acid and choline."

Molecule of the month: Acetylcholinesterase

Of course, it does not 'wait patiently': that is anthropomorphism.

3 We might think it is easy to decide if we are directly observing something, or not. But perhaps not:

"If a chemist heats some white powder, and sees it turns yellow, then this seems a pretty clear example of direct observation. But what if the chemist was rightly conscious of the importance of safe working, and undertook the manipulation in a fume cupboard, observing the phenomenon through the glass screen. That would not seem to undermine our idea of direct observation – as we believe that the glass will not make any difference to what we see. Well, at least, assuming that suitable plane glass of the kind normally used in fume cupboards has been used, and not, say a decorative multicoloured glass screen more like the windows found in many churches. Assuming, also, that there is not bright sunlight passing through a window and reflecting off the glass door of the fume cupboard to obscure the chemist's view of the powder being heated. So, assuming some basic things we could reasonably expect about fume cupboards, in conjunction with favourable viewing conditions, and taking into account our knowledge of the effect of plane glass, we would likely not consider the glass screen as an impediment to something akin to direct observation.

Might we start to question an instance of direct observation if instead of looking at the phenomenon through plane glass, there was clear, colourless convex glass between the chemist and the powder being heated? This might distort the image, but should not change the colours observed. If the glass in question was in the form of spectacle lenses, without which the chemist could not readily focus on the powder, then even if – technically – the observations were mediated by an instrument, this instrument corrects for a defect of vision such that our chemist would feel that direct observation is not compromised by, but rather requires, the glasses.

If we are happy to consider the bespectacled chemist is still observing the phenomenon rather than some instrumental indication of it, then we would presumably feel much the same about an observation being made with a magnifying glass, which is basically the same technical fix as the spectacles. So, might we consider observation down a microscope as direct observation? Early microscopes were little more than magnifying glasses mounted in stands. Modern compound microscopes use more than one lens. A system of lenses (and some additional illumination, usually) reveals details not possible to the naked eye – just as the use of convex spectacles allow the longsighted chemist to focus on objects that are too close to see clearly when unaided.

If the chemist is looking down the microscope at crystal structures in a polished slice of mineral, then, it may become easier to distinguish the different grains present by using a Polaroid filter to selectively filter some of the light reaching the eye from the observed sample. This seems a little further from what we might normally think of as direct observation. Yet, this is surely analogous to someone putting on Polaroid sunglasses to help obtain clear vision when driving towards the setting sun, or donning Polaroid glasses to help when observing the living things at the bottom of a seaside rock pool on a sunny day when strong reflections from the surface prevent clear vision of what is beneath.

A further step might be the use of an electron microscope, where the visual image observed has been produced by processing the data from sensors collecting reflections from an electron beam impacting on the sample. Here, conceptually, we have a more obvious discontinuity although the perceptual process (certainly if the image is of some salt crystal surface) may make this seem no different to looking down a powerful optical microscope. An analogy here might be using night-vision goggles that allow someone to see objects in conditions where it would be too dark to see them directly. I have a camera my late wife bought me that is designed for catching images of wildlife and that switches in low light conditions to detecting infrared. I have a picture of a local cat that triggered an image when the camera was left set up in the garden overnight. The cat looks different from how it would appear in day-light, but I still see a cat in the image (where if the camera had taken a normal image I would not have been able to detect the cat as the image would have appeared like the proverbial picture of a 'black cat in a coal cellar'). Someone using night-vision goggles considers that they see the fox, or the escaped convict, not that they see an image produced by electronic circuits.

If we accept that we can see the cat in the photograph, and the surface details of crystal grains in the electron microscope image, then can we actually see atoms in the STM [scanning tunneling microscope] image? There is no cat in or on my image, it is just a pattern of pixels that my brain determines to represent a cat. I never saw the cat directly (I was presumably asleep) so I have no direct evidence there really was a cat if I do not accept the photograph taken using infrared sensors. I believe there are cats in the world, and have seen uninvited cats in my garden in daylight, and think the camera imaged one of them at night. So it seems reasonable I am seeing a cat in the image, and therefore I might wonder if it is reasonable to doubt that I can also see atoms in an STM image.

One could shift further from simple sensory experience. News media might give the impression that physicists have seen the Higgs boson in data collected at CERN. This might lead us to ask: did they see it with their eyes? Or through spectacles? Or using a microscope? Or with night-vision goggles? Of course, they actually used particle detectors.

Feyerabend suggests that if we look at cloud chamber photographs, we do not doubt that we have a 'direct' method of detecting elementary particles …. Perhaps, but CERN were not using something like a very large cloud chamber where they could see the trails of condensation left in the 'wake' of a passing alpha particle, and that could be photographed for posterity. The detection of the Higgs involved very sophisticated detectors, complex theory about the particle cascades a Higgs particle interaction might cause, and very complex simulations to allow for all kinds of issues relating to how the performance of the detectors might vary (for example as they age) and how a signal that might be close to random noise could be identified…. No one was looking at a detector hoping to see the telltale pattern that would clearly be left by a Higgs, and only a Higgs. In one sense, to borrow a phrase, 'there's nothing to see'. Interpreting the data considered to provide evidence of the Higgs was less like using a sophisticated microscope, and more like taking a mixture of many highly complex organic substances, and – without any attempt to separate them – running a mass spectrum, and hoping to make sense of the pattern of peaks obtained.

Taber, 2019, pp.158-160

4 That is not to suggest that one should automatically assume that one molecule of a toxin can only ever damage one protein molecule somewhere in one body cell. After all, one of the reasons that CFCs (chlorofluorocarbons, which used to be used as propellants in all kinds of spray cans for example) were so damaging to the ozone 'layer' was because they could initiate a chain reaction.

In reactions that involve free radicals, each propagation step can produce another free radical to continue the reaction. Eventually two free radicals are likely to interact to terminate the process – but that might only be after a great many cycles, and the removal of a great many ozone molecules from the stratosphere. However, even if one free radical initiated the destruction of many molecules of ozone, that would still be a very small quantity of ozone, as molecules are so tiny. The problem was of course that a vast number of CFC molecules were being released.

5 So one mole of hydrogen gas, H2, is 2g, and so forth.

The baby monitor in your brain

Are our neural systems designed?

Keith S. Taber

Taking advantage of good design? (Image by Ben Kerckx from Pixabay )

"A lot of researchers talk about this [neural system] called the care-giving system which is designed to help us care for our crying babies".

Assoc. Prof. Sara Konrath

The reference to the 'design' of a human neural system caught my attention. The reference was made by Dr Sara Konrath, Associate Professor of Philanthropic Studies at the Lilly Family School of Philanthropy at Indiana University, who was interviewed for the BBC radio programme 'The Anatomy of Kindness'.

As a scientist, I found the reference to 'design' out of place, as it is a term that would often be avoided in a scientific account.

A BBC radio programme and podcast

Design in nature

Mention of 'design' in the context of natural phenomena is of note because of the history of the idea, and its role in key philosophical questions (such as the nature of the world, the purpose of our lives, the origins of good and evil, and other such trifling matters).

The notion of design was very important in natural theology, which looked at 'the book of nature' as God's works, and as offering insight into God as creator. A key argument was that the intricacy of nature, and the way life seemed to encompass such complex interlinked systems that perfectly fitted together into an overarching ecology, could only be explained in terms of a designer who was the careful architect of the whole creation.

Perhaps the most famous example of this argument was that of William Paley who wrote an entire book (1802) making the case with a vast range of examples. He started with the now famous analogy of someone who found a pocket watch on crossing a heath. Had he kicked a stone on his trip, he would have thought little of how the stone came to be there – but a watch was a complex mechanism requiring a large number of intricate parts that had to be just the right size, made of the right kind of materials, and put together in just the right way to function. No reasonable person could imagine the watch had just happened to come about by chance events, and so, by a similar argument, how could anything as subtle and complex as a human body have just emerged by accident and not have been designed by some great intelligence?

If you came across this object lying on the ground, what might you infer? (Image by anncapictures from Pixabay)

Paley's book does a wonderful job of arguing the case, and, even if some of the examples look naive from two centuries on, it was the work of someone who knew a great deal about anatomy, and the natural history of his time, and knew how to build up 'one long argument'. 1 It must have seemed very convincing to many readers at the time (especially as most would have read it from a position of already assuming there was an omniscient and all-powerful creator, and that the types of animals and plants on earth had not substantially changed their forms since their creation).

Indeed, a fair proportion of the world's population would still consider the argument sound and convincing today. That is despite Charles Darwin having suggested, about half a century later, in his own long argument 1 that there was another alternative (than an intelligent designer or simply chance formation of complex organisms and ecosystems). The title of one of Richard Dawkin's most famous books, The Blind Watchmaker (1988), championing the scientific position first developed by Darwin (and Alfred Russel Wallace) is a direct reference to Paley's watch on the heath.

The modern scientific view, supported by a vast amount of evidence from anatomy, genetics, paleontology, geology and other areas is that life evolved on earth over a vast amount of time from common ancestral unicellular organisms (which it is thought themselves evolved from less complex systems over a very long period).

Has science ruled out design?

This does not mean that science has completely ruled out the possibility that modern life-forms could have been designed. Science does rule out the possibility that modern organisms were created 'as is' (i.e., 'as are'), so if they were designed then the designer not only designed their forms, but also the highly complex processes by which they might evolve and the contingencies which made this possible. (That can be seen as an even greater miracle, and even stronger evidence of God's capabilities, of course.) What science does not do is to speculate on first causes which are not open to scientific investigation. 2

Many of the early modern scientists had strong religious convictions – including faith in an intelligent creator – and saw science as work that was totally in keeping with their faith, indeed often as a form of observance: a way of exploring and wondering at God's work. Science, philosophy and theology were often seen as strongly interlinked.

However, the usual expectation today is that science, being the study of nature, has no place for supernatural explanations. Scientists are expected to adopt 'methodological naturalism', which means looking for purely natural mechanisms and causes. 3

Read about science and religion

Arguments from design invoke teleology, the idea that nature has purpose. This makes for lazy science – as we do not need to seek natural mechanisms and explanations if we simply argue that

  • the water molecule was designed to be a shape to form hydrogen bonds, or that
  • copper is a good conductor because its molecular structure was designed for that purpose, or that
  • uranium is subject to radioactive decay because the nucleus of a uranium atom was designed to be unstable

Science has (and so a scientist, when doing her science, should have) nothing to say about the existence of a creator God, and has no view on whether aspects of the natural world might reflect such a creator's design; so arguments from design have no place in scientific accounts and explanations. This is why I honed in on the reference to design.

The evolution of empathy?

The reference was in relation to empathy. The presenter, Dr Claudia Hammond, asked rhetorically "empathy … how did it evolve?", and then introduced an interview clip: "Here's Sara Konrath, Associate Professor at the Lilly Family School of Philanthropy at Indiana University in the U.S." This was followed by Dr Konrath stating:

"A lot of researchers talk about this thing called the care-giving system which is designed to help us care for our crying babies. So, think about a crying baby for a minute that is not your own. You are on an airplane, think about that. [She laughs] And probably what you are hoping for is that baby will stop crying, [Hammond: 'absolutely'], I guess.

We need to have a biological system that will make us feel compassion for that little crying baby and figure out what's wrong so we can make the baby feel better. So, there's a whole neural system that's called the care-giving system, that activates oxytocin which is a hormone that helps us to basically reduce stress and feel close and connected, and as you can imagine that would help us want to change that little nappy or whatever the baby needs. * And that same brain system doesn't seem to distinguish too much, well, you know, we can use that, that same system to care for other people in our lives that we know or even strangers, and even people who are different than us."

Assoc. Prof. Sara Konrath

Now, as pointed out above, accepting evolution (as the vast majority of natural scientists do) does not logically exclude design – but to be consistent it requires the design not only of the intended structure, but also of the entire natural system which will give rise to it. And evolution, a natural process, is open to scientific investigation, whereas claims of design rely on extra-scientific considerations. Moreover, as evolution is an ongoing process, one might suggest that references to 'this stage in the design-realisation process' might be more appropriate.

One way of explaining the apparent inconsistency here ("how did it evolve?"…"designed to help us") is to simply assume that I am being much too literal, as surely Dr Konrath was speaking metaphorically. We can talk about 'the design' of the kidney, or a flower, or of a cow's digestive system, meaning the structure, the layout, the assemblage – without meaning to suggest 'the design' had been designed. Although Dr Konrath referred to the neural system being designed, it is quite possible she was speaking metaphorically.

But can we beleive what we (think we) hear?

A listener can reasonably assume, from the editing of the programme, that Dr Konrath was asked, and was answering, the question 'how did empathy evolve?' Yet this is only implied ("…how did it evolve? Here's Sara Konrath…") – the clip of Dr Konrath does not include any interview questions.

A journalist has to edit a programme together, to offer a narrative a listener can easily follow, so it is likely an interview would be edited down to select the most useful material. Indeed, when transcribing, I suspected that there was an edit at the point I have marked * above. I could not hear any evidence of an edit, BUT to my ears the speech was not natural in moving between "…whatever the baby needs" and "And that same brain system…". Perhaps I am wrong. But, perhaps there was a pause, or a 'false start', edited out to tidy the clip; or perhaps some material deemed less pertinent or too technical for present purposes was removed. Or, possibly, the order of the material has been changed if the speaker had responded to a number of questions, and it was felt a re-ordering of segments of different responses offered a better narrative.

All of that would be totally acceptable, as long as it was done without any intention to distort what the speaker had said. Indeed, in analysing and presenting research material from interviews or written texts, one approach is known as editing. 4 I have used this myself, to select text from different points in an interview to build up a narrative that can summarise an informant's ideas succinctly (e.g., Taber, 2008 5). This needs to be done carefully, but as long as an effort is made to be true to the person's own ideas (as the researcher understands them from the data) and this methodological technique is explicitly reported to readers, it is a valid approach and can be very effective.

Read about approaches to qualitative data analysis

A convincing argument?

Perhaps, if Dr Konrath was indeed asked 'how did empathy evolve?' this was a rather unfair question. Unlike some anatomical structures, empathy does not leave direct evidence in the fossil record. This might explain a not entirely convincing response.

The gist of the clip, as I assume a listener was meant to understand it, was along the lines.

How did empathy evolve?

  • babies cannot look after themselves and need support
  • they cry to get attention when they need help
  • a system evolved to ensure that others around the baby would pay attention to its cries, and feel compassionate, and so help it
  • the system either has the side effect of, or has evolved over time, allowing us to be empathetic more generally so we support people who need help

Perhaps that narrative is correct, and perhaps there is even scientific evidence for it. But, in terms of what I actually hear Dr Konrath say, I do not find a strong evolutionary account, but rather something along the lines:

  • We have a biological system known as the care-giving system, that activates a hormone that reduces stress and helps us feel close and connected to others
  • this allows us to feel compassion for people in need
  • encouraging us to care for other people, largely indiscriminately
  • even strangers, such as a crying baby

When I reframe ('edit') the interview that way, I do not see any strong case for why this system is designed specifically to help us care for our crying babies – but nor is there any obvious evolutionary argument. 6

If one approaches this description with a prior assumption that such things have evolved through natural selection then Dr Konrath's words can certainly be readily interpreted to be consistent with an evolutionary narrative. 6 However, someone who did not accept evolution and had a metaphysical commitment to seeing the natural world as evidence for a designer would surely be able to understand the interview just as well within that frame. I suspect both Paley and Darwin would have been able to work this material into their arguments.

Works cited:
  • Darwin, C. (1859/2006). The Origin of Species. In E. O. Wilson (Ed.), From so Simple a Beginning: The four great books of Charles Darwin. New York: W. W. Norton.
  • Dawkins, R. (1988). The Blind Watchmaker. Harmondsworth, Middlesex: Penguin Books.
  • Paley, W. (1802/2006). Natural Theology: Or Evidence of the Existence and Attributes of the Deity, Collected from the Appearances of Nature (M. D. Eddy & D. Knight Eds.). Oxford: Oxford University Press.
  • Taber, K. S. (2008). Exploring Conceptual Integration in Student Thinking: Evidence from a case study. International Journal of Science Education, 30 (14), 1915-1943. (DOI: 10.1080/09500690701589404.)
  • Taber, K. S. (2013). Conceptual frameworks, metaphysical commitments and worldviews: the challenge of reflecting the relationships between science and religion in science education. In N. Mansour & R. Wegerif (Eds.), Science Education for Diversity: Theory and practice (pp. 151-177). Dordrecht: Springer. [Download manuscript version]

Note:

1 The term 'one long argument' was used by Darwin to describe his thesis in the Origin of Species.

2 I write loosely here: science does not do anything; rather, it is scientists that act. Yet it would not be true to claim scientists do not speculate on first causes which are not open to scientific investigation. Many of them do. (Dawkins, for example, seems very certain there is no creator God.) However, that is because scientists are people and so have multiple identities. Just as nothing stops a scientist also being a mother or a daughter; nothing stops them being ice skaters, break dancers or poets. So, scientists do speculate outside of the natural realm – but then they are doing something other than science, as when they write limericks. (And perhaps something where their scientific credentials suggest no special expertise.)

3 Unfortunately, this can mislead learners into thinking science is atheistic and scientists necessarily atheists:

"The tradition in Western science (with its tendencies towards an analytical and reductionist approach) to precede as though the existence and potential role of God in nature is irrelevant to answering scientific questions, if not explicitly explained to
students, may well give the impression that because science (as a socio-cultural activity) does not need to adopt the hypothesis of the divine, scientists themselves (as individuals sharing membership of various social groups with their identities as scientists) eschew such an idea."

Taber, 2013: 153

4 This process would need to be made explicit in research, where it is normally just accepted as standard practice in journalism. These two activities can be seen as quite similar, especially when research is largely based on reports from various informants. A major difference however is that whereas researchers often have months to collect, analyse and report data, journalists are often expected to move on to the next story or episode within days, so may be working under considerable time pressures.

5 For example,

"Firstly the interview transcript was reworked into a narrative account of the interview based around Alice's verbatim responses, but following the chronology of the interview schedule in the order of the questions….The next stage of the analysis involved reorganising the case material into themes in terms of the main concepts used in Alice's explanations…This process produced a case account that was reduced (in this case to about 1,000 words), and which summarises the ways Alice used ideas in her interview."

Taber, 2008: 1926

6 One can imagine researchers asking themselves how this indiscriminate system for helping others in need arose, and someone suggesting that perhaps it was originally to make sure mothers attended to their own babies, but as a 'false negative' would be so costly (if you do not notice your baby is unfed, or has fallen in the lake, or is playing with the tiger cubs…) the system was over-sensitive and tolerated 'false positives' (leading to people attending to unrelated babes in need), and even got triggered by injured or starving adults – which it transpired increased fitness for the community, so was selected for…

It can be much easier to invent feasible-sounding evolutionary 'just-so stories' than rigorously testing them!

The earth's one long-term objective

Scientist reveals what the earth has been trying to do

Keith S. Taber

Seismology – the study of the earth letting off steam? (Image by ELG21 from Pixabay)

"the earth has one objective, it has had one objective for four and half billion years, and that's…"

In our time

'In Our Time' is an often fascinating radio programme (and podcast) where Melvyn Bragg gets three scholars from a field to explain some topic to a general audience.

Imagine young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.

The programme covers various aspects of culture.

BBC 'In our time'

I am not sure if the reason that I sometimes find the science episodes seem a little less erudite than those in the the other categories is:

  • a) Melvyn is more of an arts person, so operates at a different level in different topics;
  • b) I am more of a science person, so more likely to be impressed by learning new things in non-science topics; and to spot simplifications, over-generalisations, and so forth, in science topics.
  • c) A focus in recent years on the importance of the public understanding of science and science communication means that scientists may (often, not always) be better prepared and skilled at pitching difficult topics for a general audience.
  • d) Topics from subjects like history and literature are easier to talk about to a general audience than many science topics which are often highly conceptual and technical.

Anyway, today I did learn something from the episode on seismology ("Melvyn Bragg and guests discuss how the study of earthquakes helps reveal Earth's secrets [sic]"). I was told what the earth had been up to for the last four and half billion years…

Seismology: Where does this energy come from?

Quite early in the discussion Melvyn (sorry, The Lord Bragg CH – but he is so familiar from his broadcasts over the years that he seems like an old friend) interjected when Dr James Hammond (Reader in Geophysics at Birkbeck, University of London) was talking about forces involved in plate tectonics to ask "Where does this energy come from?". To this, Dr Hammond replied,

"The whole thing that drives the whole caboose?

It comes from plate tectonics. So, essentially the earth has one objective, it has had one objective for four and half billion years, and that's to cool down. We're [on] a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from the the material coming together, and it's trying to cool down."

Dr James Hammond talking on 'In Our Time' 1

My immediate response, was that this was teleology – seeing purpose in nature. But actually, this might be better described as anthropomorphism. This explanation presents the earth as being the kind of agent that has an objective, and which can act in the world to work towards goals. That is, like a human:

  • The earth has an objective.
  • The earth tries to achieve its objective.

Read about teleology

Read about anthropomorphism

A flawed scientific account?

Of course, in scientific terms, the earth has no such objective, and it is not trying to do anything as it is inanimate. Basic thermodynamics suggests that an object (e.g., the earth) that is hotter than its surroundings will cool down as it will radiate heat faster than it absorbs it. 2 (Of course, the sun is hotter than the earth – but that's a rather minority component of the earth's surroundings, even if in some ways a very significant one.) Hot objects tend to cool down, unless they have an active mechanism to maintain their temperature above their ambient backgrounds (such as 'warm-blooded' creatures). 3

So, in scientific terms, this explanation might be seen as flawed – indeed as reflecting an alternative conception of similar kind as when students explain evolutionary adaptations in terms of organisms trying to meet some need (e.g., The brain thinks: grow more fur), or explain chemical processes in terms of atoms seeking to meet a need by filling their electron shells (e.g., Chlorine atoms share electrons to fill in their shells).

Does Dr Hammond really believe this account?

Does Dr Hammond really think the earth has an objective that it actively seeks to meet? I very much doubt it. This was clearly rhetorical language adopting tropes seen as appropriate to meet the needs of the context (a general audience, a radio programme with no visuals to support explanations). In particular, he was in full flow when he was suddenly interrupted by Melvin, a bit like the annoying child who interrupts the teacher's carefully prepared presentation by asking 'but why's that?' about something it had been assumed all present would take for granted.

Imagine the biology teacher trying to discuss cellular metabolism when young Melvin asks 'but where did the sugar come from?'; or the chemistry teacher discussing the mechanism of a substitution reaction when young Melvin asks why we are assuming tetrahedral geometry around the carbon centre of interest; or young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.

Of course, part of Melvin's job in chairing the programme IS to act as the child who does not understand something being taken for granted and not explained, so vicariously supporting the listener without specialist background in that week's topic.

Effective communication versus accurate communication?

Science teachers and communicators have to sometimes use ploys to 'make the unfamiliar familiar'. One common ploy is to employ an anthropomorphic narrative as people readily relate to the human experience of having goals and acting to meet needs and desires. Locating difficult ideas within such a 'story' framework is known to often make such ideas more accessible. Does this gain balance the potential to mislead people into thinking they have been given a scientific account? In general, such ploys are perhaps best used only as introductions to a difficult topic, introductions which are then quickly followed up by more technical accounts that better match the scientific narrative (Taber & Watts, 2000).

Clearly, that is more feasible when the teacher or communicator has the opportunity for a more extensive engagement with an audience, so that understanding can be built up and developed over time. I imagine Dr Hammond was briefed that he had just a few minutes to get across his specific points in this phase of the programme, only to then find he was interrupted and asked to address additional background material.

As a scientist, the notion of the earth spending billions of years trying to cool down grates as it reflects pre-scientific thinking about nature and acts as a pseudo-explanation (something which has the form of an explanation, but little substance).

Read about pseudo-explanations

As cooling is a very familiar everyday phenomena, I wondered if a basic response that would avoid anthropomorphism might have served, e.g.,

When the earth formed, it was very much hotter than today, and, as it was hotter than its surroundings, it has been slowly cooling ever since by radiating energy into space. Material inside the earth may be hot enough to be liquid, or – where solid – be plastic enough to be deformed. The surface is now much cooler than it was, but inside the earth it is still very hot, and radioactive processes continue to heat materials inside the earth. We can understand seismic events as driven by the ways heat is being transferred from deep inside the earth.

However, just because I am a scientist, I am also less well-placed to know how effective this might have been for listeners without a strong science background – who may well have warmed [sic] to the earth striving to cool.

Dr Hammond had to react instantly (like a school teacher often has to) and make a quick call based on his best understanding of the likely audience. That is one of the difference between teaching (or being interviewed by Melvin) and simply giving a prepared lecture.

Work cited:

Taber, K. S. and Watts, M. (1996) The secret life of the chemical bond: students' anthropomorphic and animistic references to bonding, International Journal of Science Education, 18 (5), pp.557-568.

Note

1 Speech often naturally has repetitions, and markers of emphasis, and hesitations that seem perfectly natural when heard, but which do not match written language conventions. I have slightly tidied what I transcribed from:

"The whole thing that drives the whole caboose? It comes from plate tectonics, right. So, essentially the earth, right, has one objective, it has had one objective for four and half billion years, and that's to cool down. Right, we're a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from, from the the material coming together,4 and it's trying to cool down."

2 In simple terms, the hotter an object is, the greater the rate at which it radiates.

The hotter the environment is, the more intense the radiation incident on the object and the more energy it will absorb.

Ultimately, in an undisturbed, closed system everything will reach thermal equilibrium (the same temperature). Our object still radiates energy, but at the same rate as it absorbs it from the environment so there is no net heat flow.

3 Historically, the earth's cooling was an issue of some scientific controversy, after Lord Kelvin (William Thomson) calculated that if the earth was cooling at the rate his models suggested for a body of its mass, then this was cooling much too rapid for the kind of timescales that were thought to be needed for life to have evolved on earth.

4 This is referring to the idea that the earth was formed by the coming together of material (e.g., space debris from a supernova) by its mutual gravitational attraction. Before this happens the material can be considered to be in a state of high gravitational potential energy. As the material is accelerated together it acquires kinetic energy (as the potential energy reduces), and then when the material collides inelastically it forms a large mass of material with high internal energy (relating to the kinetic and potential energy of the molecules and ions at the submicroscopic level) reflected in a high temperature.

Viruses may try to hide, but

other microbes are not accepting defeat

Keith S. Taber

viruses might actually try to…hide…
the microbes did not just accept defeat, they have been mounting their resistance

qutoes from an 'Inside Science' episode
A recent episode of the BBC radio programme/podcast inside science

I was catching up on the BBC Radio 4 science programme/podcast 'Inside Science' episode 'Predicting Long Covid, and the Global Toll of Antimicrobial Resistance' (first broadcast 27 January 2022) and spotted anthropomorphic references to microbes in two different items.

What is 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.

Read about anthropomorphism

Viruses may try to hide from the immune system

The first example was from the lead story about 'long COVID'.

Prof. Onur Boyman, Director of the Department of Immunology at the University Hospital, Zurich, was interviewed after his group published a paper suggesting that blood tests may help identify people especially susceptible to developing post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) – which has become colloquially known as 'long COVID'.

"We found distinct patterns of total immunoglobulin (Ig) levels in patients with COVID-19 and integrated these in a clinical prediction score, which allowed early identification of both outpatients and hospitalized individuals with COVID-19 that were at high risk for PACS ['long COVID']."

Cervia, Zurbuchen, Taeschler, et al., 2022, p.2

The study reported average patterns of immunoglobulins found in those diagnosed with COVID-19 (due to SARS-CoV-2 infection), and those later diagnosed with PACS. The levels of different types of immunoglobulins (designated as IgM, etc.) were measured,

Differentiating mild versus severe COVID-19, IgM was lower in severe compared to mild COVID-19 patients and healthy controls, both at primary infection and 6-month follow-up… IgG3 was higher in both mild and severe COVID-19 cases, compared to healthy controls …In individuals developing PACS, we detected decreased IgM, both at primary infection and 6-month follow-up… IgG3 tended to be lower in patients with PACS…which was contrary to the increased IgG3 concentrations in both mild and severe COVID-19 cases…

Cervia, Zurbuchen, Taeschler, et al., 2022, p.3

Viruses in a defensive mode

In the interview, Professor Boyman discussed how features of the immune system, and in particular immunoglobulins, were involved in responses to infection, and made the comment:

"IgG3…is smaller than IgM and therefore it is able to go into many more tissues. It is able to cross certain tissue barriers and go into those sites where viruses might actually try to go to and hide"

Prof. Onur Boyman interviewed on 'BBC Inside Science'
Micro-organisms trying to hide? (Image by WikiImages from Pixabay )

This is anthropomorphic as it refers to viruses trying to hide from the immune components. Of course, viruses are not sentient, so they do not try to do anything: they have no intentions. Although viruses might well pass across tissue barriers and move into tissues where they are less likely to come into contact with immunoglobulins, 'hiding' suggests a deliberate behaviour – which is not the case.

Professor Boyman is clearly aware of that, and either deliberately or otherwise was speaking metaphorically. Scientifically literate people would not be misled by this as they would know viruses are not conscious agents. However, learners are not always clear about this.

The bacteria, however, are going on the offensive

The other point I spotted was later in the same programme when the presenter, Gaia Vince, introduced an item about antibiotic resistance:

"Back in my grandparent's time, the world was a much more dangerous place with killer microbes lurking everywhere. People regularly died from toothache, in childbirth, or just a simple scratch that got infected. But at the end of the second world war, doctors had a new miracle [sic] drug called penicillin. Antibiotics have proved a game changer, taking the deadly fear away from common infections. But the microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback."

Gaia Vince presenting 'Inside Science'

Antibiotics are generally ineffective against viruses, but have proved very effective treatments for many bacterial infections, including those that can be fatal when untreated. The functioning of antibiotics can be explained by science in purely natural terms, so the label of 'miracle drugs' is a rhetorical flourish: their effect must have seemed like a miracle when they first came into use, so this can also be seen as metaphoric language.

Read about metaphors in science

Bacteria regrouping for a renewed offensive? (Image by WikiImages from Pixabay )

However, again the framing is anthropomorphic. The suggestion that microbes could 'accept defeat' implies they are the kind of entities able to reflect on and come to terms with a situation – which of course they are not. The phrase 'mounting resistance' also has overtones of deliberate action – but again is clearly meant metaphorically.

Again, there is nothing wrong with these kinds of poetic flourishes in presenting science. Most listeners would have heard "microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback" and would have spontaneously understood the metaphoric use of language without suspecting any intention to suggest microbes actually behave deliberately. Such language supports the non-specialist listener in accessing a technical science story.

Some younger listeners, however, may not have a well-established framework for thinking about the nature of an organism that is able to reflect on its situation and actively plan deliberate behaviours. After all, a good deal of children's literature relies on accepting that various organisms, indeed non-living entities such as trains, do have human feelings, motives and behavioural repertoires. (Learners may for example think that evolutionary adaptations, such as having more fur in a cold climate, are mediated by conscious deliberation.) Popular science media does a good job of engaging and enthusing a broad audience in science, but with the caveat that accessible accounts may be open to misinterpretation.

Work cited:

NASA puts its hand in the oven

A tenuous analogy

Keith S. Taber

The Parker Solar Probe

I recently listened to NASA's Nicky Fox being interviewed about the Parker Solar Probe which (as the name suggests) is being used to investigate the Sun.

Screenshot from http://parkersolarprobe.jhuapl.edu (© 2019 The Johns Hopkins University Applied Physics Laboratory LLC. All rights reserved. Permission for use requested.)

There is a website for the project which, when I accessed it (28th December 2021), suggested the spacecraft was 109 279 068 km from the Sun's surface (which I must admit would have got a marginal comment on one of my own student's work along the lines "is the Sun's surface so distinctly positioned that this level of precision can be justified?") and travelling at 57 292 kph (kilometers per hour). This unrealistic precision derives from the details being based on "mission performance modeling [sic] and simulation and not real-time data…" Real-time data is not necessarily available to the project team itself – the kind of shielding needed to protect the spacecraft from such extreme conditions also creates a challenge in transmitting data back to earth.

But the serious point is that returning to the website at another time it is possible to see how the probe's speed and position have changed (as shown on 'the Mission' webpage – indeed by the time I took the 'screenshot' it had moved about 7000 km), as the spacecraft moves through a sequence of loops in space orbiting the Sun on a shifting elliptical path that takes it periodically very close (very close, in solar system terms, that is) to the sun. Like any orbiting body, the probe will be moving faster when closest to the sun and slowest when furthest from the sun. (The balance shifts between its kinetic and potential energy – as it works to move away against the sun's gravity when receding from it 1.)

Touching the Sun

Publicity still from the Danny Boyle film 'Sunshine'

Getting too close the Sun – with its high temperature, the 'solar wind' of charged particles emitted into space, occasional solar flares, and the high flux of radiation from across the electromagnetic spectrum – is very dangerous, making the design and engineering of any craft intended to investigate our local star up close very challenging. A key feature is a protective heat shield facing the Sun . This was the premise of the sci-fi film 'Sunshine' 2.

For the Parker probe

"the spacecraft and instruments will be protected from the Sun's heat by a …11.43 cm carbon-composite shield, which will need to withstand temperatures outside the spacecraft that reach nearly …1,377 degrees Celsius"

"At closest approach to the Sun, while the front of Parker Solar Probe' solar shield faces temperatures approaching … 1,400° Celsius, the spacecraft's payload will be near room temperature, at about [29˚C.]."

http://parkersolarprobe.jhuapl.edu

Note: Dr Fox is NOT reporting from the Parker Solar Probe – just pictured in front of an image of the sun (Dr Fox's profile on NASA website)

Dr Fox, who is Director of NASA's Heliophysics [physics of the Sun] Division, was being interviewed about data released from an earlier close approach on a BBC Science in Action podcast.

Science in Action episode broadcast 2021-12-19

"The Parker Solar probe continues its mission of flying closer and closer to the sun. Results just published show what the data the probe picked up when it dipped into the surrounding plasma. NASA's Nicky Fox is our guide."

Item on BBC Science in Action

The project is framing that event as when, "For the first time in history, a spacecraft has touched the Sun". Although the visible surface of the sun has a temperature of about 6000K (incredibly hot by human standards), the temperature of the 'atmosphere' or corona around it is believed to reach several million Kelvins. On the programme, Dr Fox was asked about how the spacecraft could survive in the sun's corona, given its extremely high temperatures.

A teaching analogy?

In response she used an analogy from everyday experience:

"We talk about the plasma being at a couple of million degrees, it's like putting your hand inside an oven, and you don't touch anything. You won't burn your hand, you'll feel some heat but you won't actually burn your hand, and so the solar wind itself, or the corona, is a very tenuous plasma, there are just not that many particles there. So, even though the whole atmosphere is at about two million degrees, the number of particles that are coming into contact with the spacecraft are [sic] very small.

The temperatures that we have to deal with are about fourteen, fifteen hundred degrees Celsius, at the maximum, which is still hot, don't…let me kid you, that's still hot, but it is not two million degrees."

Dr Fox interviewed on Science in Action

Analogies are commonly used in science, science communication and science education as one means of 'making the unfamiliar familiar' by showing how something novel or surprising is actually like something the audience is already aware of and comfortable with.

Read about science analogies

Read about making the unfamiliar familiar

If the probe had been dipped in a molten vat of some hypothetical refractory liquid at two million degrees it would have quickly been destroyed. But because the Corona is not only a plasma (an 'ionised gas')3, but a very tenuous one, this does not happen. NASA sending the probe into the corona is similar to putting one's hand in the oven when cooking. If you touch the metal around the outside you will burn yourself, but you are able to reach inside without damage as long as you do not touch the sides – as although the air in the oven can get as hot as the metal structure, it has a very low particle density compared with a solid metal. So, your hand is in a hot place, but is not in contact with much of the hot material.

Do not try this at home – at least not unless you are quick

Of course, this is not the whole story. You can reach in the oven to put something in or (with suitable protection) take something out, but you cannot safely leave your hand in there for any length of time.

When two objects at different temperature are placed in contact, heating will occur with 'heat' passing from the hotter to colder object until they are in thermal equilibrium (i.e., at the same temperature). But this is not instantaneous – it takes time.4 If the Parker Solar Probe had been flown into the Sun's atmosphere and left there it would have been heated till it eventually matched the ambient temperature (not 'just' 1400˚C) regardless of how effective a heat shield it had been given. Or rather, it would have been heated till its substance reached the ambient temperature, as it would have lost structural integrity long before this point.

Of course, the probe has been designed to spend some time in the coronal atmosphere collecting data, but to only dip in for short visits, as NASA is well aware that it would not be wise to leave one's hand in the oven for too long.

Note:

1 This at least is the description based on Newtonian physics. There is an attractive, gravitational force between the Sun and the probe. As the spacecraft moves towards the sun it accelerates, and then its momentum takes it away, being decelerated by gravity.In this model gravity is a force between two bodies. (The path is actually more complex than this, as it has been designed to fly past Venus several times to adjust its trajectory round the Sun.)

In the model offered by general relativity the probe simply moves in a straight line through space which has a complex geometry due to the presence of matter/energy: a straight line which seems to us to be a shifting series of ellipses. Gravity here is best understood as a distortion from a 'flat' space. Perhaps it is clear why for most purposes scientists stick with the Newtonian description even though it is no longer the account considered to best describe nature.

2 The movie poster gives a slight clue to the hazards involved in taking a manned mission to the Sun!

3 Plasma is considered a fourth state of matter: solid, liquid, gas, plasma. The expression that 'a plasma is an ionised gas' may suggest plasma is a kind of gas, but then we might also say that a gas is a boiled liquid or that a liquid is melted solid! So, perhaps what we should say is that a plasma [gas/liquid] is what you get when you ionise [boil/melt] a gas [liquid/solid].

4 In theory, modelling of such a process suggests it takes an infinite time for this to occur. 5 In practice, the temperatures become close enough that for practical purposes we consider thermal equilibration to have occurred.

5 This is an example of a process that can be understood as having a negative feedback cycle: temperature difference drives the heat flow, which reduces temperature difference, which therefore also reduces the driver for heat flow; so the rate of heat flow is reduced, so therefore the rate of temperature change is reduced… This is a similar pattern to radioactive decay – both follow an 'exponential decay' law.

Of opportunistic viruses and meat-eating bees

The birds viruses and the bees do it: Let's do it, let's…evolve

Keith S. Taber

bees that once were vegetarian actually decided to change their ways…

this group of bees realised that there's always animals that are dying and maybe there's enough competition on the flowers [so] they decided to switch

How the vulture bee got its taste for meat

I was struck by two different examples of anthropomorphism that I noticed in the same episode of the BBC's Science in Action radio programme/podcast.

Science in Action episode broadcast 5th December 2021

Anthropomorphism in science?

Anthropomorphism is the name given treating non-human entities as if they were human actors. An example of anthropomorphic language would be "the atom wants to donate an electron so that it can get a full outer shell" (see for example: 'A sodium atom wants to donate its electron to another atom'). In an example such as that, an event that would be explained in terms of concepts such as force and energy in a scientific account (the ionisation of an atom) is instead described as if the atom is a conscious agent that is aware of its status, has preferences, and acts to bring about desired ends.

Read about Anthropomorphism

Of course, an atom is not a complex enough entity to have mental experience that allows it to act deliberately in the world, so why might someone use such language?

  • Perhaps, if the speaker was a young learner, because they have not been taught the science.
  • Perhaps a non-scientist might use such language because they can only make sense of the abstract event in more familiar terms.

But what if the speaker was a scientist – a science teacher or a research scientist?

When fellow professionals (e.g., scientists) talk to each other they may often use a kind of shorthand that is not meant to be taken literally (e.g., 'the molecule wants to be in this configuration') simply because it can shorten and simplify more technical explanations that both parties understand. But when a teacher is talking to learners or a scientist is trying to explain their ideas to the general public, something else may be going on.

Read about Anthropomorphism in public science discourse

Anthropomorphism in science communication and education

In science teaching or science communication (scientists communicating science to the public) there is often a need to present abstract or complex ideas in ways that are accessible to the audience. At one level, teaching is about shifting what is to be taught from being unfamiliar to learners to being familiar, and one way to 'make the unfamiliar familiar' is to show it is in some sense like something already familiar.

Therefore there is much use of simile and analogy, and of telling stories that locate the focal material to be learned within a familiar narrative. Anthropomorphism is often used in this way. Inanimate objects may be said to want or need or try (etc.) as the human audience can relate to what it is to want or need or try.

Such techniques can be very useful to introduce novel ideas or phenomena in ways that are accessible and/or memorable ('weak anthropomorphism'). However, sometimes the person receiving these accounts may not appreciate their figurative nature as pedagogic / communicative aids, and may mistake what is meant to be no more than a starting point, a way into a new topic or idea, as being the scientific account itself. That is, these familiarisation techniques can work so well that the listener (or reader) may feel satisfied with them as explanatory accounts ('strong anthropomorphism').

Evolution – it's just natural (selection)

A particular issue arises with evolution, when often science only has hypothetical or incomplete accounts of how and why specific features or traits have been selected for in evolution. It is common for evolution to be misunderstood teleologically – that is, as if evolution was purposeful and nature has specific end-points in mind.

Read about teleology

The scientific account of evolution is natural selection, where none of genes, individual specimens, populations or species are considered to be deliberately driving evolution in particular directions (present company excepted perhaps – as humans are aware of evolutionary processes, and may be making some decisions with a view to the long-term future). 1

Yet describing evolutionary change in accord with the scientific account tends to need complex and convoluted language (Taber, 2017). Teleological and anthropomorphic shorthand is easier to comprehend – even if it puts a burden on the communicatee to translate the narrative into a more technical account.

What the virus tries to do

The first example from the recent Science in Action episode related to the COVID pandemic, and the omicron variant of the SARS-CoV-2 virus. This was the lead story on the broadcast/podcast, in particular how the travel ban imposed on Southern Africa (a case of putting the lid on the Petri dish after the variant had bolted?) was disrupting supplies of materials needed to address the pandemic in the countries concerned.

This was followed by a related item:

"Omicron contains many more mutations than previous variants. However scientists have produced models in the past which can help us understand what these mutations do. Rockefeller University virologist Theodora Hatziioannou produced one very similar to Omicron and she tells us why the similarities are cause for concern."

https://www.bbc.co.uk/programmes/w3ct1l4p

During this item, Dr Theodora Hatziioannou noted:

"When you give the virus the opportunity to infect so many people, then of course it is going to try not only every possible mutation, but every possible combination of mutations, until it finds one that really helps it overcome our defences."

Dr Theodora Hatziioannou interviewed on Science in Action

Dr Theodora Hatziioannou
Research Associate Professor
Laboratory of Retrovirology
The Rockefeller University

I am pretty sure that Dr Hatziioannou does not actually think that 'the virus' (which of course is composed of myriad discrete virus particles) is trying out different mutations intending to stop once it finds one which will overcome human defences. I would also be fairly confident that in making this claim she was not intending her listeners to understand that the virus had a deliberate strategy and was systematically working its way through a plan of action. A scientifically literature person should readily interpret the comments in a natural selection framework (e.g., 'random' variation, fitness, differential reproduction). In a sense, Dr Hatziioannou's comments may be seen as an anthropomorphic analogy – presenting the 'behaviour' of the virus (collectively) by analogy with human behavior.

Yet, as a science educator, such comments attract my attention as I am well aware that school age learners and some adult non-scientists may well understand evolution to work this way. Alternative conceptions of natural selection are very common. Even when students have been taught about natural selection they may misunderstand the process as Lamarckian (the inheritance of acquired characteristics – see for example 'The brain thinks: grow more fur'). So, I wonder how different members of the public hearing this interview will understand Dr Hatziioannou's analogy.

Even before COVID-19 came along, there was a tendency for scientists to describe viruses in such terms as as 'smart', 'clever' and 'sneaky' (e.g., 'So who's not a clever little virus then?'). The COVID pandemic seems to have unleashed a (metaphorical) pandemic of public comments about what the virus wants, and what it tries to achieve, and so forth. When a research scientist talks this way, I am fairly sure it is intended as figurative language. I am much less sure when, for example, I hear a politician telling the public that the virus likes cold weather ('What COVID really likes').

Vulture bees have the guts for it

The other item that struck me concerned vulture bees.

"Laura Figueroa from University of Massachusetts in Amhert [sic] in the US, has been investigating bees' digestive systems. Though these are not conventional honey bees, they are Costa Rican vulture bees. They feed on rotting meat, but still produce honey."

https://www.bbc.co.uk/programmes/w3ct1l4p
Bees do not actually make reasoned choices about their diets
(Original image by Oldiefan from Pixabay)

The background is that although bees are considered (so I learned) to have evolved from wasps, and to all have become vegetarians, there are a few groups of bees that have reverted to the more primitive habits of eating meat. To be fair to them, these bees are not cutting down the forests to set up pasture and manage livestock, but rather take advantage of the availability of dead animals in their environment as a source of protein.

These vulture bees (or carrion bees) are able to do this because their gut microbiomes consist of a mix of microbes that can support them in digesting meat, allowing them to be omnivores. This raises the usual kind of 'chicken and egg' question 1 thrown up by evolutionary developments: how did vegetarian bees manage to shift their diet: the more recently acquired microbes would not have been useful or well-resourced whilst the bees were still limiting themselves to a plant-based diet, but the vegetarian bees would not have been able to digest carrion before their microbiomes changed.

As part of the interview, Dr Figueroa explaied:

"These are more specialised bees that once they were vegetarian for a really long time and they actually decided to change their ways, there's all of this meat in the forest, why not take advantage? I find that super-fascinating as well, because how do these shifts happen?

Because the bees, really when we are thinking about them, they've got access to this incredible resource of all of the flowering plants that are all over the world, so then why switch? Why make this change?

Over evolutionary time there are these mutations, and, you know, maybe they'd have got an inkling for meat, it's hard to know how exactly that happened, but really because it is a constant resource in the forest, there's always, you know, this might sound a little morbid but there's always animals that are dying and there's always this turn over of nutrients that can happen, and so potentially this specialised group of bees realised that, and maybe there's enough competition on the flowers that they decided to switch. Or, they didn't decide, but it happened over evolutionary time.

Dr Laura Figueroa interviewed on Science in Action

Dr Figueroa does not know exactly how this happened – more research is needed. I am sure Dr Figueroa does not think the bees decided to change their ways in the way that a person might decide to change their ways – perhaps deciding to get more exercise and go to bed earlier for the sake of their health. I am also sure Dr Figueroa does not think the bees realised that there was so much competition feeding on the flowers that it might be in their interests to consider a change of diet, in the way that a person might decide to change strategy based on an evaluation of the competition. These are anthropomorphic figures of speech.

Dr Laura Figueroa, NSF Postdoctoral Research Fellow in Biology
Department of Entomology, Cornell University / University of Massachusetts in Amherst

As she said "they didn't decide, but it happened over evolutionary time". Yet it seems so natural to use that kind of language, that is to frame the account in a narrative that makes sense in terms of how people experience their lives.

Again, the scientifically literate should appreciate the figurative use of language for what it is, and it is difficult to offer an accessible account without presenting evolutionary change as purposive and the result of deliberation and strategy. Yet, I cannot help wondering if this kind of language may reinforce some listeners' alternative conceptions about how natural selection works.

Work cited:
Notes

1 The 'selfish' gene made famous by Dawkins (1976/1989) is not really selfish in the sense a person might be – rather this was an analogy which helped shift attention from changes at the individual or species level when trying to understand how evolution occurs, to changes in the level of distinct genes. If a mutation in a specific gene leads to a change in the carrying organism that (in turn) leads to that specimen having greater fitness then the gene itself has an increased chance of being replicated. So, from the perspective of focusing on the genes, the change at the species level can be seen as a side effect of the 'evolution' of the gene. The gene may be said to be (metaphorically) selfish because it does not change for the benefit of the organism, but to increase its own chances of being replicated. Of course, that is also an anthropomorphic narrative – actually the gene does not deliberately mutate, has no purpose, has no notion of replication, indeed, does not even 'know' it is a gene, and so forth.

2 Such either/or questions can be understood as posing false dichotomies (here, either the bees completely changed their diets before their microbiomes or their microbiomes changed dramatically before their diets shifted) when what often seems most likely is that change has been slow and gradual.

When being almost certain is no better than a guess

Scientific discourse and the media

Keith S. Taber

"I picked up that phrase 'almost certainly due to lack of vaccine', I mean that sounds like a bit of guesswork."

Presenter on the BBC Radio 4 Today programme

Yesterday, I was drafting a post about how a scientist had referred to a scientific theory being 'absolutely certain'. I suggested that this seemed at odds with the nature of science as producing conjectural knowledge always open to revisiting – yet might be considered necessary when seeking to communicate in public media.

Today, I sadly heard an excellent example to support that thesis.

BBC Radio 4's Today programme included an interview with Dr Raghib Ali

That example concerned Nick Robinson (BBC journalist, and former Political Editor) introducing an interview with Dr Raghib Ali on the radio news programme, 'Today'. Dr Ali is a Senior Clinical Research Associate at the MRC Epidemiology Unit at the University of Cambridge.

Robinson: "Now one of the first things we learned when the pandemic began, was that a greater proportion of Black and South Asian people were dying from corona virus. That remains the case many months on, but a new government report out today argues that the mortality gap now is mainly due, is not due, I'm sorry, to any genetic or social factor, it is, and I quote almost certainly down to vaccine take-up, or more accurately a lack of vaccine take-up. We're joined now by the government's independent expert advisor on COVID-19 and ethnicity, Dr. Raghib Ali, who is a consultant in acute medicine at Oxford University Hospitals. Morning to you"

Dr Ali: "Good morning Nick."

Robinson:"I picked up that phrase 'almost certainly due to lack of vaccine', I mean that sounds like a bit of guesswork. Do we actually know that?"

Nick Robinson interviewing Dr Raghib Ali on Today, 3rd December 2021, c.08.46

This seems to show a worrying level of ignorance (or else an odd provocation) from a senior and experienced journalist expecting scientific studies to be able to offer certain knowledge about causes in complex multivariate social situations.

How a scientific claim was understood on a prestigious news magazine programme

Yesterday, I was asking whether Dr Friederike Otto should have referred to scientists knowing something with 'absolute certainty' when speaking in the broadcast media. Today I heard an example of how the media can treat any scientific claim that is not framed as being absolutely certain.

Sadly, if the news media are only interested in absolute certainty, then they should stop talking to scientists about their work as absolute certainty has no place in scientific discourse. Nor should it, I might suggest, have a place in serious journalism.

Climate change – either it is certain OR it is science

Is there a place for absolute certainty in science communication?

Keith S. Taber

I just got around to listening to the podcast of the 10th October episode of Science in Action. This was an episode entitled 'Youngest rock samples from the moon' which led with a story about rock samples collected on the moon and brought to earth by a Chinese mission (Chang'e-5). However, what caused me to, metaphorically at least, prick up my ears was a reference to "absolute certainty".

BBC Science in Action episode, 10th October, 2021

Now the tag line for Science in Action is "The BBC brings you all the week's science news". I think that phrase reveals something important about science journalism – it may be about science, but it is journalism, not science.

That is not meant as some kind of insult. But science in the media is not intended as science communication between scientists (they have journals and conferences and so forth), but science communicated to the public – which means it has to be represented in a form suitable for a general, non-specialist audience.

Read about science in public discourse and the media

Scientific and journalistic language games

For, surely, "all the week's science news" cannot be covered in one half-hour broadcast/podcast. 1

My point is that "The BBC brings you all the week's science news" is not intended to be understood and treated as a scientific claim, but as something rathere different. As Wittgenstein (1953/2009) famously pointed out, language has to be understood in specific contexts, and there are different 'language games'. So, in the genre of the scientific report there are particular standards and norms that apply to the claims made. Occasionally these norms are deliberately broken – perhaps a claim is made that is supported by fabricated evidence, or for which there is no supporting evidence – but this would be judged as malpractice, academic misconduct or at least incompetence. It is not within the rules of that game

However, the BBC's claim is part of a different 'language game' – no one is going to be accused of professional misconduct because, objectively, Science in Action does not brings a listener all the week's science news. The statement is not intended to be understood as an objective knowledge claim, but more a kind of motto or slogan; it is not to be considered 'false' because it not objectively correct. Rather, it is to be understood in a fuzzy, vague, impressionistic way.

To ask whether "The BBC brings you all the week's science news" through Science in Action is a true or false claim would be a kind of category error. The same kind of category error that occurs if we ask whether or not a scientist believes in the ideal gas law, the periodic table or models of climate change.

Who invented gravity?

This then raises the question of how we understand what professional academic scientists say on a science news programme that is part of the broadcast media in conversation with professional journalists. Are they, as scientists, engaged in 'science speak', or are they as guests on a news show engaged in 'media speak'?

What provoked this thought with was comments by Dr Fredi Otto who appeared on the programme "to discuss the 2021 Nobel Prizes for Science". In particular, I was struck by two specific comments. The second was:

"…you can't believe in climate change or not, that would just be, you believe in gravity, or not…"

Dr Friederike Otto speaking on Science in Action

Which I took to mean that gravity is so much part of our everyday experience that it is taken-for-granted, and it would be bizarre to have a debate on whether it exists. There are phenomena we all experience all the time that we explain in terms of gravity, and although there may be scope for debate about gravity's nature or its mode of action or even its universality, there is little sense in denying gravity. 2

Newton's notion of gravity predominated for a couple of centuries, but when Einstein proposed a completely different understanding, this did not in any sense undermine the common ('life-world' 2) experience labelled as gravity – what happens when we trip over, or drop something, or the tiring experience of climbing too many steps. And, of course, the common misconception that Newton somehow 'discovered' gravity is completely ahistorical as people had been dropping things and tripping over and noticing that fruit falls from trees for a very long time before Newton posited that the moon was in freefall around the earth in a way analogous to a falling apple!

Believing in gravity

Even if, in scientific terms, believing in a Newtonian conceptualisation of gravity as a force acting at a distance would be to believe something that was no longer considered the best scientific account (in a sense the 'force' of gravity becomes a kind of epiphenomenon in a relativistic account of gravity); in everyday day terms, believing in the phenomenon of gravity (as a way of describing a common pattern in experience of being in the world) is just plain common sense.

Dr Otto seemed to be suggesting that just as gravity is a phenomenon that we all take for granted (regardless of how it is operationalised or explained scientifically), so should climate change be. That might be something of a stretch as the phenomena we associate with gravity (e.g., dense objects falling when dropped, ending up on the floor when we fall) are more uniform than those associated with climate change – which is of course why one tends to come across more climate change deniers than gravity deniers. To the best of my knowledge, not even Donald Trump has claimed there is no gravity.

But the first comment that gave me pause for thought was:

"…we now can attribute, with absolute certainty, the increase in global mean temperature to the increase in greenhouse gases because our burning of fossil fuels…"

Dr Friederike Otto speaking on Science in Action
Dr Fredi Otto has a profile page at the The Environmental Change Unit,
University of Oxford

Absolute certainty?

That did not seem to me like a scientific statement – more like the kind of commitment associated with belief in a religious doctrine. Science produces conjectural, theoretical knowledge, but not absolute knowledge?

Surely, absolute certainty is limited to deductive logic, where proofs are possible (as in mathematics, where conclusions can be shown to inevitably follow from statements taken as axioms – as long as one accepts the axioms, then the conclusions must follow). Science deals with evidence, but not proof, and is always open to being revisited in the light of new evidence or new ways of thinking about things.

Read about the nature of scientific knowledge

Science is not about belief

For example, at one time many scientists would have said that the presence of an ether 3 was beyond question (as for example waves of light travelled from the sun to earth, and waves motion requires a medium). Its scientific characterisation -e.g., the precise nature of the ether, its motion relative to the earth – were open to investigation, but its existence seemed pretty secure.

It seemed inconceivable to many that the ether might not exist. We might say it was beyond reasonable doubt. 4 But now the ether has gone the way of caloric and phlogiston and N-rays and cold fusion and the four humours… It may have once been beyond reasonable doubt to some (given the state of the evidence and the available theoretical perspectives), but it can never have been 'absolutely certain'.

To suggest something is certain may open us to look foolish later: as when Wittgenstein himself suggested that we could be certain that "our whole system of physics forbids us to believe" that people could go to the moon.

Science is the best!

Science is the most reliable and trustworthy approach to understanding the natural world, but a large part of that strength comes from it never completely closing a case for good – from never suggesting to have provided absolute certainty. Science can be self-correcting because no scientific idea is 'beyond question'. That is not to say that we abandon, say, conversation of energy at the suggestion of the first eccentric thinker with designs for a perpetual motion machine – but in principle even the principle of conservation of energy should not be considered as absolutely certain. That would be religious faith, not scientific judgement.

So, we should not believe. It should not be considered absolutely certain that "the increase in global mean temperature [is due to] the increase in greenhouse gases because [of] our burning of fossil fuels", as that suggests we should believe it as a doctrine or dogma, rather than believe that the case is strong enough to make acting accordingly sensible. That is, if science is always provisional, technically open to review, then we can never wait for absolute certainty before we act, especially when something seems beyond reasonable doubt.

You should not believe scientific ideas

The point is that certainty and belief are not really the right concepts in science, and we should avoid them in teaching science:

"In brief, the argument to be made is that science education should aim for understanding of scientific ideas, but not for belief in those ideas. To be clear, the argument is not just that science education should not intend to bring about belief in scientific ideas, but rather that good science teaching discourages belief in the scientific ideas being taught."

Taber, 2017: 82

To be clear – to say that we do not want learners to believe in scientific ideas is NOT to say we want them to disbelieve them! Rather, belief/disbelief should be orthogonal to the focus on understanding ideas and their evidence base.

I suggested above that to ask whether "The BBC brings you all the week's science news" through Science in Action is a true or false claim would be a kind of category error. I would suggest it is a category error in the same sense as asking whether or not people should believe in the ideal gas law, the periodic table, or models of climate change.

"If science is not about belief, then having learners come out of science lessons believing in evolution, or for that matter believing that magnetic field lines are more concentrated near the poles of a magnet, or believing that energy is always conserved, or believing that acidic solutions contain solvated hydrogen ions,[5] misses the point. Science education should help students understand scientific ideas, and appreciate why these ideas are found useful, and something of their status (for example when they have a limited range of application). Once students can understand the scientific ideas then they become available as possible ways of thinking about the world, and perhaps as notions under current consideration as useful (but not final) accounts of how the world is."

Taber, 2017: 90

But how do scientists cross the borders from science to science communication?

Of course many scientists who have studied the topic are very convinced that climate change is occurring and that anthropogenic inputs into the atmosphere are a major or the major cause. In an everyday sense, they believe this (and as they have persuaded me, so do I). But in a strictly logical sense they cannot be absolutely certain. And they can never be absolutely certain. And therefore we need to act now, and not wait for certainty.

I do not know if Dr Otto would refer to 'absolute certainty' in a scientific context such as a research paper of a conference presentation. But a radio programme for a general audience – all ages, all levels of technical background, all degrees of sophistication in appreciating the nature of science – is not a professional scientific context, so perhaps a different language game applies. Perhaps scientists have to translate their message into a different kind of discourse to get their ideas across to the wider public?

The double bind

My reaction to Dr Otto's comments derived from a concern with public understanding of the nature of science. Too often learners think scientific models and theories are meant to be realistic absolute descriptions of nature. Too often they think science readily refutes false ideas and proves the true ones. Scientists talking in public about belief and absolute certainty can reinforce these misconceptions.

On the other hand, there is probably nothing more important that science can achieve today than persuade people to act to limit climate change before we might bring about shifts that are (for humanity if not for the planet) devastating. If most people think that science is about producing absolute certain knowledge, then any suggestion that there is uncertainty over whether human activity is causing climate change is likely to offer the deniers grist, and encourage a dangerous 'well let's wait till we know for sure' posture. Even when it is too late and the damage has been done, if there are any scientists left alive, they still will not know absolutely certainly what caused the changes.

"…Lord, here comes the flood
We'll say goodbye to flesh and blood
If again the seas are silent
In any still alive
It'll be those who gave their island to survive…"

(Peter Gabriel performing on the Kate Bush TV special, 1979: BBC Birmingham)

So, perhaps climate scientists are in a double bind – they can represent the nature of science authentically, and have their scientific claims misunderstood; or they can do what they can to get across the critical significance of their science, but in doing so reinforce misconceptions of the nature of scientific knowledge.

Coda

I started drafting this yesterday: Thursday. By coincidence, this morning, I heard an excellent example of how a heavyweight broadcast journalist tried to downplay a scientific claim because it was couched as not being absolutely certain!

Works cited:

Notes

1 An alternative almost tautological interpretation might be that the BBC decides what is 'science news', and it is what is included in Science in Action, might fit some critics complaints that the BBC can be a very arrogant and self-important organisation – if only because there are stories not covered in Science in Action that do get covered in the BBC's other programmes such as BBC Inside Science.

2 This might be seen as equivalent to saying that the life-world claim that gravity (as is commonly understood and experienced) exists is taken-for-granted Schutz & Luckmann, 1973). A scientific claim would be different as gravity would need to be operationally defined in terms that were considered objective, rather that just assuming that everyone in the same language community shares a meaning for 'gravity'.

3 The 'luminiferous' aether or ether. The ether was the name given to the fifth element in the classical system where sublunary matter was composed of four elements (earth, water, air, fire) and the perfect heavens from a fifth.

(Film  director Luc Besson's sci-fi/fantasy movie 'The Fifth Element' {1997, Gaumont Film Company} borrows from this idea very loosely: Milla Jovovich was cast in the title role as a perfect being who is brought to earth to be reunited with the other four elements in order to save the world.)

4 Arguably the difference between forming an opinion on which to base everyday action (everyday as in whether to wear a rain coat, or to have marmalade on breakfast toast, not as in whether to close down the global fossil fuel industry), and proposing formal research conclusions can be compared to the difference between civil legal proceedings (decided on the balance of probabilities – what seems most likely given the available evidence) and criminal proceedings – where a conviction is supposed to depend upon guilt being judged beyond reasonable doubt given the available evidence (Taber, 2013).

Read about writing-up research

5 Whether acids do contain hydrated hydrogen ions may seem something that can reasonably be determined, at least beyond reasonable doubt, by empirical investigation. But actually not, as what counts as an acid has changed over time as chemists have redefined the concept according to what seemed most useful. (Taber, 2019, Chapter 6: Conceptualising acids: Reimagining a class of substances).

We didn't start the fire (it was the virus)

A simile for viral infection

Keith S. Taber

Could an oral Covid-19 treatment be available soon?

There was an item on the BBC radio programme/podcast 'Science in Action' (23rd September 2021) about anti-viral agents being used in response to the COVID-19 pandemic: 'Could an oral Covid-19 treatment be available soon?'

Science in Action – 23/09/2021

In discussing early trials of a new potential treatment, Molnupiravir 1, Daria Hazuda (Vice President of Infectious Disease and Vaccines at Merck Research Labs and Chief Scientific Officer of MRL Cambridge) made the point that in viral infections the virus may trigger an immune response which is responsible for aspects of the illness, and which may continue even when there is no longer active virus present. As part of her interview comments she said:

"But even after someone is infected, the host actually mounts, for all these [respiratory] viruses, a really dramatic immune and inflammatory response. So it sort of lights a fire. And even when the virus stops replicating, you know that fire continues to burn, and in a lot of cases that's what lands people in the hospital. And so you want to prevent the virus from igniting that fire, that is what really ends up causing a huge amount of damage to the patient. …

the greatest benefit [of the antiviral drug being tested] is in the outpatient setting before that fire gets ignited."

Daria Hazuda being interviewed on 'Science in Action'

A scientific simile

Science communicators, such as teachers, but also scientists and journalists presenting science in the public media, often use techniques to 'make the unfamiliar familiar', to get across abstract or difficult ideas in ways that their audience can relate to.

These techniques can include analogies, metaphors and similes. Here Dr Hazuda used an analogy between the damage to tissue that can occur in disease, and the damage a fire can do. In particular, she was suggesting that the virus may be seen as like something which ignites a fire (such as a match or a spark) but which is not needed to keep the fire going once it had taken hold.

She introduced this idea by suggesting that the virus "sort of lights a fire". This can be considered a simile, which is a figure of speech which is a kind of explicit comparison where one thing is said to be like or similar to another.2 Dr Hazuda did not suggest that the virus actually lights a fire, but rather it has an effect which can be considered somewhat like ('sort of') igniting a fire.

"We didn't start the fire
It was always burning, since the world's been turning
We didn't start the fire
No, we didn't light it, but we tried to fight it"

Billy Joel

Viruses triggering long term disease

The symptoms we experience when ill can be the results of our immune system reacting to illness, rather than the direct effect of the disease causing agent. That does not mean the disease itself would not harm us (infectious agents may be destroying cells which would not be obvious until extensive damage was done), but that in some conditions what we notice – perhaps sneezing, coughing, a raised temperature – is due to the immune response.

The immediate context of the Science in Action interview was the current COVID-19 pandemic caused by infection with the SARS-CoV-2 virus. However, the idea that a viral infection may trigger ('ignite') a longer term immune response (the 'fire') is not new with COVID. The syndrome sometimes known as chronic fatigue syndrome has unknown cause(s), but viruses are among the suspects. Viruses have been suspected as being a possible trigger (if perhaps in combination with other factors) in a range of autoimmune conditions. In autoimmune conditions the mechanisms that usually protect a person from infectious agents such as (some) bacteria and viruses attack and destroy the person's own cells leading to inflammation and potentially serious tissue damage.

People might commonly say that the immune system is 'meant' or 'intended' to protect us from diseases and that it sometimes 'goes wrong' leading to autoimmune disease – but strictly this is not a scientific way of thinking. The immune system has no purpose as such (this would be 'teleological' thinking), but has just evolved in ways such that it has on balance increased fitness.

From that perspective, it might not seem so strange that our immune systems are sometimes insufficient to protect us from harm, and yet can also sometimes be over-sensitive and start doing damage – as that surely is what we might expect if evolution has (through natural selection) led to a system which has tended on the whole to be protective.

The admirable HLA-B27?

"HLA B27 plays an admirable, perhaps outstanding role in the immune response to viruses, however, it is also directly involved in the pathogenesis of the spondyloarthropathies"

Bowness, 2002: 866

My late wife Philippa was diagnosed with a complex autoimmune condition – she was told that she had atypical Wegener's granulomatosis (a disease now usually called Granulomatosis with polyangiitis 2), a form of vasculitis (a disease leading to inflammation in the blood vessels), and that she might have been genetically susceptible to autoimmune diseases because she produced a particular type of human leukocyte antigen, HLA-B27. HLA is an important component of human immune systems, but the precise antigens a person produces varies, depending on their genes (just as we all have blood but people can be assigned into different blood groups). It was also suggested to her that an otherwise minor infection may have acted as a trigger in setting off the autoimmune problems.

Medicine today has some effective agents such as steroids that help 'dampen down' the 'fires' that damage tissues in autoimmune diseases. But these conditions can be very serious. Fifty years ago, most people found to have Wegener's granulomatosis were dead from that damage within a year of their diagnosis.

HLA-B27 is only found in a minority of people in most populations and is associated with a higher prevalence of certain immune conditions such as ankylosing spondylitis (an inflammatory condition especially affecting the spine), inflammatory bowel disease, and some forms of arthritis. It might seem odd that evolution has not led to the elimination of HGLA-B27 if it is associated with serious medical conditions. Yet, again, it may be that something which can make people prone to some conditions may also be better at protecting them from others.

People with HLA-B27 may be better at mounting an effective immune response to some viral infections (the fire is more readily ignited, we might say) and this might be enough of an advantage to balance its unfortunate role in autoimmune conditions. Over human history, HLA-B27 might have protected a great many people from dangerous infections, if also being responsible for a smaller number becoming very ill.

"HLA-B27 appears to excel at its natural function of binding and presenting viral peptide epitopes to cytotoxic T cells. We have suggested that HLA-B27 may, however, act as a 'double-edged sword'. Thus, certain features of its peptide binding ability or cell biology (perhaps those favouring excellent antiviral responses) might also lead to autoimmunity."

McMichael & Bowness, 2002: S157

That is, what makes this immune component so good at attacking certain viruses (as if the immune system had been doused in petrol so that the slightest spark might initiate a response) may also be responsible for its association with autoimmune diseases. HLA-B27 may (metaphorically) be the can of petrol that means that a viral spark starts not just a fire, but a conflagration.

Read about science in public discourse and the media

Read about making the unfamiliar familiar

Read about science similes

Read about teleological explanations


Work cited:

Bowness, P. (2002). HLA B27 in health and disease: a double‐edged sword? Rheumatology, 41(8), 857-868. doi:10.1093/rheumatology/41.8.857

McMichael, A., & Bowness, P. (2002). HLA-B27: natural function and pathogenic role in spondyloarthritis. Arthritis research, 4 Suppl 3(Suppl 3), S153-S158. doi:10.1186/ar571

Footnotes:

1: "the first oral, direct-acting antiviral shown to be highly effective at reducing nasopharyngeal SARS-CoV-2 infectious virus" according to a preprint reported at medRχiv). A preprint is a paper written to report scientific research but NOT yet tested through peer review and formally published, and so treated as reporting more provisional and uncertain findings than a peer-reviewed paper.

2 By comparison, a metaphor may be considered an implicit comparison presented as if an identity: e.g., the nucleus is the brain of the cell.

2. The disease was named after the German physician Friedrich Wegener who described the condition. After Wegener was identified as a Nazi and likely war criminal (suspected, but not convicted) it was decided to rename the disease.

What COVID really likes

Researching viral preferences

Keith S. Taber

When I was listening to the radio news I heard a clip of the Rt. Hon. Sajid Javid MP, the U.K. Secretary of State for Health and Social Care, talking about the ongoing response to the COVID pandemic:

Health Secretary Sajid Javid talking on 12th September

"Now that we are entering Autumn and Winter, something that COVID and other viruses, you know, usually like, the prime minister this week will be getting out our plans to manage COVID over the coming few months."

Sajid Javid

So, COVID and other viruses usually like Autumn and Winter (by implication, presumably, in comparison with Spring and Summer).

This got me wondering how we (or Sajid, at least) could know what the COVID virus (i.e., SARS-CoV-2 – severe acute respiratory syndrome coronavirus 2) prefers – what the virus 'likes'. I noticed that Mr Javid offered a modal qualification to his claim: usually. It seemed 'COVID and other viruses' did not always like Autumn and Winter, but usually did.

Yet there was a potential ambiguity here depending how one parsed the claim. Was he suggesting that

[COVID and other viruses]

usually

like Autumn and Winter		orCOVID

[and other viruses usually]

like Autumn and Winter

This might have been clearer in a written text as either

COVID and other viruses usually like Autumn and WinterorCOVID, and other viruses usually, like Autumn and Winter

The second option may seem a little awkward in its phrasing, 1 but then not all viral diseases are more common in the Winter months, and some are considered to be due to 'Summer viruses':

"Adenovirus, human bocavirus (HBoV), parainfluenza virus (PIV), human metapneumovirus (hMPV), and rhinovirus can be detected throughout the year (all-year viruses). Seasonal patterns of PIV are type specific. Epidemics of PIV type 1 (PIV1) and PIV type 3 (PIV3) peak in the fall [Autumn] and spring-summer, respectively. The prevalence of some non-rhinovirus enteroviruses increases in summer (summer viruses)"


Moriyama, Hugentobler & Iwasaki, 2020: 86

Just a couple of days later Mr Javid was being interviewed on the radio, and he made a more limited claim:

Health Secretary Sajid Javid talking on BBC Radio 4's 'Today' programme, 15th September

"…because we know Autumn and Winter, your COVID is going to like that time of year"

Sajid Javid

So, this claim was just about the COVID virus, not viruses more generally, and that we know that COVID is going to like Autumn and Winter. No ambiguity there. But how do we know?

Coming to knowledge

Historically there have been various ways of obtaining knowledge.

  • Divine revelation: where God reveals the knowledge to someone, perhaps through appearing to the chosen one in a dream.
  • Consulting an oracle, or a prophet or some other kind of seer.
  • Intuiting the truth by reflecting on the nature of things using the rational power of the human intellect.
  • Empirical investigation of natural phenomena.

My focus in this blog is related to science, and given that we are talking about public health policy in modern Britain, I would like to think Mr Javid was basing his claim on the latter option. Of course, even empirical methods depend upon some metaphysical assumptions. For example, if one assumes the cosmos has inbuilt connections one might look for evidence in terms of sympathies or correspondences. Perhaps, if the COVID virus was observed closely and looked like a snowflake, that could (in this mindset) be taken as a sign that it liked Winter.

A snowflake – or is it a virus particle?
(Image by Gerd Altmann from Pixabay)

Sympathetic magic

This kind of correspondence, a connection indicated by appearance, was once widely accepted, so that a plant which was thought to resemble some part of the anatomy might be assumed to be an appropriate medicine for diseases or disorders associated with that part of the body.

This is a kind of magic, and might seem a 'primitive' belief to many people today, but such an idea was sensible enough in the context of a common set of underlying beliefs about the nature and purposes of the world, and the place and role of people in that world. One might expect that specific beliefs would soon die out if, for example, the plant shaped like an ear turned out to do nothing for ear ache. Yet, at a time when medical practitioners could offer little effective treatment, and being sent to a hospital was likely to reduce life expectancy, herbal remedies at least often (if not always) did no harm.

Moreover, many herbs do have medicinal properties, and something with a general systemic effect might work as topical medicine (i.e., when applied to a specific site of disease). Add to that, the human susceptibility to confirmation bias (taking more notice of, and giving more weight to, instances that meet our expectations than those which do not) and the placebo effect (where believing we are taking effective medication can sometimes in itself have beneficial effects) and the psychological support offered by spending time with an attentive practitioner with a good 'bedside' manner – and we can easily see how beliefs about treatments may survive limited definitive evidence of effectiveness.

The gold standard of experimental method

Of course, today, we have the means to test such medicines by taking a large representative sample of a population (of ear ache sufferers, or whatever), randomly dividing them into two groups, and using a double-blind (or should that be double-deaf) approach, treat them with the possible medicine or a placebo, without either the patient or the practitioner knowing who was getting which treatment. (The researchers have a way to know of course – or it would difficult to deduce anything from the results.) That is, the randomised control trial (RCT).

Now, I have been very critical of the notion that these kinds of randomised experimental designs should be automatically be seen as the preferred way of testing educational innovations (Taber, 2019) – but in situations where control of variables and 'blinding' is possible, and where randomisation can be applied to samples of well-defined populations, this does deserve to be considered the gold standard. (It is when the assumptions behind a research methodology do not apply that we should have reservations about using it as a strategy for enquiry.)

So can the RCT approach be used to find out if COVID has a preference for certain times of year? I guess this depends on our conceptual framework for the research (e.g., how do we understand what a 'like' actually is) and the theoretical perspective we adopt.

So, for example, behaviourists would suggest that it is not useful to investigate what is going on in someone's mind (perhaps some behaviorists do not even think the mind concept corresponds to anything real) so we should observe behaviours that allow us to make inferences. This has to be done with care. Someone who buys and eats lots of chocolate presumably likes chocolate, and someone who buys and listens to a lot of reggae probably likes reggae, but a person who cries regularly, or someone that stumbles around and has frequent falls, does not necessary like crying, or falling over, respectively.

A viral choice chamber

So, we might think that woodlice prefer damp conditions because we have put a large number of woodlice in choice chambers with different conditions (dry and light, dry and dark, damp and light, damp and dark) and found that there was a statistically significant excess of woodlice settling down in the damp sections of the chamber.

Of course, to infer preferences from behaviour – or even to use the term 'behaviour' – for some kinds of entity is questionable. (To think that woodlice make a choice based on what they 'like' might seem to assume a level of awareness that they perhaps lack?) In a cathode ray tube electrons subject to a magnetic field may be observed (indirectly!) to move to one side of the tube, just as woodlice might congregate in one chamber, but I am not sure I would describe this as electrons liking that part of the tube. I think it can be better explained with concepts such as electrical charge, fields, forces, and momentum.

It is difficult to see how we can do double blind trials to see which season a virus might like, as if the COVID virus really does like Winter, it must surely have a way of knowing when it is Winter (making blinding impossible). In any case, a choice chamber with different sections at different times of the year would require some kind of time portal installed between its sections.

Like electrons, but unlike woodlice, COVID viral particles do not have an active form of transport available to them. Rather, they tend to be sneezed and coughed around and then subject to the breeze, or deposited by contact with surfaces. So I am not sure that observing virus 'behaviour' helps here.

So perhaps a different methodology might be more sensible.

A viral opinion poll

A common approach to find out what people like would be a survey. Surveys can sometimes attract responses from large numbers of respondents, which may seem to give us confidence that they offer authentic accounts of widespread views. However, sample size is perhaps less important than sample representativeness. Imagine carrying out a survey of people's favourite football teams at a game at Stamford Bridge; or undertaking a survey of people's favourite bands as people queued to enter a King Crimson concert! The responses may [sic, almost certainly would] not fully reflect the wider population due to the likely bias in such samples. Would these surveys give reliable results which could be replicated if repeated at the Santiago Bernabeu or at a Marillion concert?

How do we know what 'COVID 'really likes?
(Original Images by OpenClipart-Vectors and Gordon Johnson from Pixabay)

A representative sample of vairants?

This might cause problems with the COVID-19 virus (SARS-CoV-2). What counts as a member of the population – perhaps a viable virus particle? Can we even know how big the population actually is at the time of our survey? The virus is infecting new cells, leading to new virus particles being produced all the time, just as shed particles become non-viable all the time. So we have no reliable knowledge of population numbers.

Moreover, a survey needs a representative sample: do the numbers of people in a sample of a human population reflect the wider population in relevant terms (be that age, gender, level of educational qualifications, earnings, etc.)? There are viral variants leading to COVID-19 infection – and quite a few of them. That is, SARS-CoV-2 is a class with various subgroups. The variants replicate to different extents under particular conditions, and new variants appear from time to time.

So, the population profile is changing rapidly. In recent months in the UK nearly all infections where the variant has been determined are due to the variant VOC-21APR-02 (or B.1.617.2 or Delta) but many people will be infected asymptotically or with mild symptoms and not be tested, and so this likely does not mean that VOC-21APR-02 dominates the SARS-CoV-2 population as a whole to the extent it currently dominates in investigated cases. Assuming otherwise would be like gauging public opinion from the views of those particular people who make themselves salient by attending a protest, e.g.:

"Shock finding – 98% of the population would like to abolish the nuclear arsenal,

according to a [hypothetical] survey taken at the recent Campaign for Nuclear Disarmament march"

In any case, surveys are often fairly blunt instruments as they need to present objectively the same questions to all respondents, and elicit responses in a format that can be readily classified into a discrete number of categories. This is why many questionnaires use Likert type items:

Would you say you like Autumn and Winter:

12345
AlwaysNearly alwaysUsuallySometimesNever

Such 'objective' measures are often considered to avoid the subjective nature of some other types of research. It may seem that responses do not need to be interpreted – but of course this assumes that the researchers and all the respondents understand language the same way (what exactly counts as Autumn and Winter? What does 'like' mean? How is 'usually' understood – 60-80% of the time, or 51-90% of the time or…). We can usually (sic) safely assume that those with strong language competence will have somewhat similar understandings of terms, but we cannot know precisely what survey participants meant by their responses or to what extent they share a meaning for 'usually'.

There are so-called 'qualitative surveys' which eschew this kind of objectivity to get more in-depth engagement with participants. They will usually use interviews where the researcher can establish rapport with respondents and ask them about their thoughts and feelings, observe non-verbal signals such as facial expressions and gestures, and use follow-up questions… However, the greater insight into individuals comes at a cost of smaller samples as these kinds of methods are more resource-intensive.

But perhaps Mr Javid does not actually mean that COVID likes Autumn and Winter?

So, how did the Department of Health & Social Care, or the Health Secretary's scientific advisors, find out that COVID (or the COVID virus) likes Autumn and Winter? The virus does not think, or feel, and it does not have preferences in the way we do. It does not perceive hot or cold, and it does not have a sense of time passing, or of the seasons.2 COVID does not like or dislike anything.

Mr Javid needs to make himself clear to a broad public audience, so he has to avoid too much technical jargon. It is not easy to pitch a presentation for such an audience and be pithy, accurate, and engaging, but it is easy for someone (such as me) to be critical when not having to face this challenge. Cabinet ministers, unlike science teachers, cannot be expected to have skills in communicating complex and abstract scientific ideas in simplified and accessible forms that remain authentic to the science.

It is easy and perhaps convenient to use anthropomorphic language to talk about the virus, and this will likely make the topic seem accessible to listeners, but it is less clear what is actually meant by a virus liking a certain time of year. In teaching the use of anthropomorphic language can be engaging, but it can also come to stand in place of scientific understanding when anthropomorphic statements are simply accepted uncritically at face value. For example, if the science teacher suggests "the atom wants a full shell of electrons" then we should not be surprised that students may think this is a scientific explanation, and that atoms do want to fill their shells. (They do not of course. 3)

Image by Gordon Johnson from Pixabay

Of course Mr Javid's statements cannot be taken as a literal claim about what the virus likes – my point in this posting is to provoke the question of what this might be intended to mean? This is surely intended metaphorically (at least if Mr Javid had thought about his claim critically): perhaps that there is higher incidence of infection or serious illness caused by the COVID virus in the Winter. But by that logic, I guess turkeys really would vote for Christmas (or Thanksgiving) after all.

Typically, some viruses cause more infection in the Winter when people are more likely to mix indoors and when buildings and transport are not well ventilated (both factors being addressed in public health measures and advice in regard to COVID-19). Perhaps 'likes' here simply means that the conditions associated with a higher frequency/population of virus particles occur in Autumn and Winter?

A snowflake.
The conditions suitable for a higher frequency of snowflakes are more common in Winter.
So do snowflakes also 'like' Winter?
(Image by Gerd Altmann from Pixabay)

However, this is some way from assigning 'likes' to the virus. After all, in evolutionary terms, a virus might 'prefer', so to speak, to only be transmitted asymptomatically, as it cannot be in the virus's 'interests', so to speak, to encourage a public health response that will lead to vaccines or measures to limit the mixing of people.

If COVID could like anything (and of course it cannot), I would suggest it would like to go 'under the radar' (another metaphor) and be endemic in a population that was not concerned about it (perhaps doing so little harm it is not even noticed, such that people do not change their behaviours). It would then only 'prefer' a Season to the extent that that time of year brings conditions which allow it to go about its life cycle without attracting attention – from Mr Javid or anyone else.

Keith S. Taber, September 2021

Addendum: 1st December 2021

Déjà vu?

The health secretary was interviewed on 1st December

"…we have always known that when it gets darker, it gets colder, the virus likes that, the flu virus likes that and we should not forget that's still lurking around as well…"

Rt. Hon. Sajid Javid MP, the U.K. Secretary of State for Health and Social Care, interviewed on BBC Radio 4 Today programme, 1st December, 2021
Works cited:
Footnotes:

1. It would also seem to be a generalisation based on the only two Winters that the COVID-19 virus had 'experienced'

2. Strictly I cannot know what it is like to be a virus particle. But a lot of well-established and strongly evidenced scientific principles would be challenged if a virus particle is sentient.

3. Yet this is a VERY common alternative conceptions among school children studying chemistry: The full outer shells explanatory principle

Related reading:

So who's not a clever little virus then?

COVID is like a fire because…

Anthropomorphism in public science discourse

Shortlisting for disease

False positives on screening tests can be understood in relation to job applications

Keith S. Taber

I rather liked an analogy used by Dr Kit Yates of Bath University comparing medical screening to being shortlisted for a job. The context was a Royal Institution podcast entitled: Can We Trust Maths? 1

Ri Podcast available at https://soundcloud.com/royal-institution/maths-trust

This was a very informative discussion of aspects of statistics, and one of the questions addressed was:

How often do false positive and false negative test results occur in medical screenings?

Screening for disease

Screening programmes test apparently healthy members of the population for serious medical issues in order to catch problems at an early stage when treatment offers the best prognosis.

Screening programmes can quickly test many people…
(Image by Ahmad Ardity from Pixabay)

No tests are perfect, so tests will sometimes give misleading results – called false positives and false negatives.

a test result that is:when an ideal perfect test would have shown positivewhen an ideal perfect test would have shown negative
positiveis called a true positiveis called a false positive
negativeis called a false negativeis called a true negative
…but definitive diagnoses may require more sophisticated follow-up investigation
(Image by Michal Jarmoluk from Pixabay)

Sometimes tests can be tuned to avoid many false negatives by tolerating a higher rate of false positive (or vice versa). This is similar to what happens in statistical hypothesis testing when the choice of 'confidence level' (the p {for probability} value used as a cut-off criterion for 'statistical significance') can be chosen according to whether it is more important to avoid false positives or to avoid false negatives.

Choice of confidence level reflects a balance between admitting false positives (due to chance events) and false negatives (where real effects are not distinguished from chance events).
After, Taber, 2019, Fig. 7.

The notion of 'beyond reasonable doubt' used in criminal trials can be understood as based on the principle that it is better that some guilty perpetrators are not convicted at trial than to risk miscarriages of justice where innocent people may lose their liberty (or indeed in some jurisdictions, perhaps their lives). That is, it is better to have false negatives than false positives in criminal convictions.

In medical screening programmes, it is common to have an initial test which might give quite a few positive results (but hopefully not produce many false negatives, where a person with a disease appears to be clear according to the test), even though most of the positive results will prove to be false alarms (false positives) when followed up by a more sophisticated test that it is impractical or too expensive to use for mass screening.

The bias towards false positives built into some medical screening trials means that a person should not be too despondent at getting a positive result in the initial screen. Dr Yates worked through one example to show that based on the rates of false positives on certain screening tests, a person called for regular screenings over a number of years was actually more likely than not to get at least one positive screening result – but still unlikely to be unlucky enough to have the disease.

A teaching analogy

What I most liked was the use of an analogy to compare the logic of the screening process with a familiar everyday situation. Teaching can be seen as a process of making the unfamiliar familiar, and teachers often do this by comparing the unfamiliar they are charged with teaching about with something already familiar to the their students. That is only a starting point for supporting a developing understanding of the new concept or phenomenon, but it often is very useful in making abstract new ideas seem less threatening or inaccessible.

Read about making the unfamiliar familiar

One common way of making the unfamiliar familiar is through analogy: showing that what is new has a familiar conceptual structure – mapping onto a set of ideas already understood.

Read about teaching analogies

An 'outreaching' analogy?

Scientists charged with giving talks to a public audience as part of 'public communication' of science ('outreach') or attempts to improve 'public understanding' of science also have the job of making the unfamiliar familiar and may also use teaching analogies – as Dr Yates did here:

"I would make the analogy to screenings with a job interview. So, when a company wants to hire someone for a job, they send out an advert, and people send in their c.v.s. And the company can read those c.v.s quickly and make a shortlist. And that's a really cheap way, just as the first screen is a really cheap way of identifying people, who might be suitable for the job, people who might have breast cancer. And then for the job interview you call people in and you interview them and you throw 'assessment centres' at them, you do tests which are too expensive to do to the whole population at large to identify someone good for the job, but you can do it to this smaller population. And in the same way, with the screen we invite people in and we throw more expensive, more accurate tests at them to give them a diagnosis. And the point is, just because you would get invited to an interview for a job you had applied for, you wouldn't assume that you had got the job, right? So, in the same way, just because you get invited for further tests after a screen, you shouldn't assume you have the disease that is being screened for. You should wait and go to the follow-up test and see what that follow-up test says."

Dr Kit Yates explaining the logic of screening programmes
Based on an analogy used by Dr Kit Yates

This seemed a well-considered analogue, one that would be very accessible to most people in the audience. It is a common experience to have applied for jobs: perhaps sometimes not being shortlisted; sometimes called in for interview but not appointed; and sometimes being offered the job. 2

The explanations flowed nicely between the target concept (screening) and the analogue (shortlisting) – as can be seen in the tabulated version below.

"I would make the analogy to screeningswith a job interview.
So, when a company wants to hire someone for a job, they send out an advert, and people send in their c.v.s.
And the company can read those c.v.s quickly and make a shortlist.
And that's a really cheap way,
just as the first screen is a really cheap way of identifying people,
who might be suitable for the job,
people who might have breast cancer.
And then for the job interview you call people in and you interview them and you throw 'assessment centres' at them, you do tests which are too expensive to do to the whole population at large to identify someone good for the job, but you can do it to this smaller population.
And in the same way, with the screen we invite people in and we throw more expensive, more accurate tests at them to give them a diagnosis.
And the point is, just because you would get invited to an interview for a job you had applied for, you wouldn't assume that you had got the job, right?
So, in the same way, just because you get invited for further tests after a screen, you shouldn't assume you have the disease that is being screened for.
You should wait and go to the follow-up test and see what that follow-up test says."

An effective teaching analogy needs to have an analogue that is sufficiently familiar for an audience to appreciate its conceptual structure – and that structure must fit well when mapped across to the target concept. 'Medical screening is like job shortlisting' seems to work well on both these criteria.

Work cited:

Footnotes:

1: "If you see a newspaper headline with a big, bold statistic, how do you know that you can trust it? How often do false positive and false negative test results occur in medical screenings? And how do you safely bet whether or not 2 people in any room will share a birthday?
This month we hear from Kit Yates about the maths of medicine, crime and the media, exploring real-world data from his book, 'The Maths of Life and Death'.
This talk was recorded from our theatre at the Royal Institution, on 21 January 2020." https://soundcloud.com/royal-institution/maths-trust

2. It might be suggested that this process reflects a middle class /professional/white collar employment experiences, whereas for many jobs, such as much shop or factory work, an employer is likely to employ the first apparently suitable candidate that applies, rather than using a slower and more expensive two stage process. This is so, but the situation of short-listing is still generally familiar through story lines in fiction, such as in television dramas.

Of mostly natural origin

Is your shampoo of natural, unnatural, or supernatural origin?

Keith S. Taber

It seems that some of the ingredients of a well-known brand of hair care products are not of natural origin (Image by Stefan Keller from Pixabay)

A well know brand of hair products is being advertised on television with an explicit claim that the shampoo is 94% of natural origin. Clearly there is also an implicit claim here about the other 6%! This dubious claim does not seem to be a slip of the tongue, as similar references can be found in product details on line (including the examples below). The science teacher in me knew that it was this kind of nonsense which supports common misconceptions about 'natural' being inherently good, and there being a clear distinction between materials that are 'natural', and those that are not.

Shampoos from brands other than Herbal Essences are 100% of natural origin.

The other evening I was watching television, and there was a shampoo being advertised, and although I was not paying attention I thought I heard the claim that the shampoo contained products of 94% natural origin. Had I misheard – a quick 'rewind' suggested not.

My next assumption was that this was sloppy language being used by some advertising copywriter, and that the manufacturer who commissioned the commercial simply had not noticed the slip. So I had a look on line.1 It seems that the brand concerned, Herbal Essences, has a habit or topping up its products with material that is not of natural origin. The company claims it is using at least 90% materials of natural original in its latest products (see the examples below), and this is apparently seen as a positive point to stress in its marketing.

But this is just nonsense. If the shampoo was fabricated using 94% products of natural original, then 6% was not of natural origin. This leaves me to wonder where the rest originates. A shampoo, any shampoo, is 100% of natural origin.

Natural products chemistry

In chemistry there is a common term natural products which tends to be used for materials extracted from living organisms – one can extract vitamin C from oranges, and insulin for diabetics used to be extracted from pancreases from farm animals (although now it is produced by the activities of bacteria or yeast). In that sense salt (produced by evaporating sea water) and chalk (deriving from the shells debris from long dead sea organisms) are not natural products. But like everything else in the material world, salt and chalk are still of natural origin.

So what is a hair product which is not of natural origin, or which is only partially of natural origin? It seems there are two obvious contrasts to natural, which are 'unnatural' and 'supernatural'. Presumably the company was not suggesting it used ingredients of supernatural origin?

Do Herbal Essences employ a specialist formulation technologist to prepare the shampoo ingredients that are not of natural origin? (Image by pendleburyannette from Pixabay)

What makes something unnatural?

Assuming Herbal Essences products do not include material of supernatural origin, the other option would seem to be material of unnatural origin. But what makes a material unnatural.

At various times, in various cultural contexts, the divine right of kings, feudalism and slavery will have been seen as perfectly natural, as well the subservience of women to men. Certain sexual acts that are now widely (if not universally) considered part of the normal range of human behaviours have at various times in different societies been considered unnatural – indeed so unnatural that those found to have 'committed' them might be put to death.

Given that the question of 'what is human nature?' is not settled (didn't Immanuel Kant think this was the core task for philosophy?) the approach that is sometimes taken is to look instead to 'nature' herself (for nature is a 'she' as has long been established – in part justifying her domination and mistreatment by 'man'). If it happens in nature, then that's natural.

"The sun rises everyday but animals occasionally give birth to monsters. 'Natural is what occurs always or almost always', says Aristotle, generalizing from this experience."

Paul Feyerabend

So, by this criterion, saving lives with blood transfusions is not natural, and nor is hip replacement surgery, nor using an incubator to stop premature babies dying. However, cancer is natural. Pushing your siblings out of the nest, or pecking them to death, to get a greater share of the food your parents bring home is perfectly natural. Depositing your eggs in another creature, and paralysing it so that it acts as a defenseless (but alive, and so fresh) source of food when your offspring hatch out inside it, is natural.

"We can save you if you wish, but only by unnatural acts" (Image by Mohamed Hassan from Pixabay)

The man-made is not 'natural'

This depends upon demarcating humans as somehow outside of nature. This is difficult for a natural scientist to accept as 'ever since Darwin' (to borrow a phrase) it has been difficult to see how humans can be considered inherently distinct from the rest of the natural world, even if contingency has led to some obvious differences in terms of the development of culture. This argument then distinguishes the natural from the synthetic, the man-made.

A space rocket is not natural (in this sense) as it only exists because humans built it. Whether this is qualitatively different from technology elsewhere in nature – a badger's dam, a termite's nest, a honeycomb – rather than just a matter of a (admittedly impressive) difference of degree is an interesting question.

There are no doubt times where it is useful to distinguish between materials and objects that can be collected or extracted form 'natural' sources, and those that only exist because they have been synthesised by people – even if we do need to be wary of reading too much into the distinction. The Saturn V rocket did not exist 'in nature', and nor does a lemon coated in a wax so that it will stay 'fresh' longer – but one is the product of considerably less processing than the other. 2

Fluorine compounds (fluorides) are added to drinking water in many places to help protect teeth, but in other places the water supply already (i.e., 'naturally') contains fluoride at much higher levels – indeed, sometimes high enough to be considered a medical risk. This both reminds us that what is natural is somewhat arbitrary, and that what is considered natural is not necessarily desirable.

Natural and natural origin

The Saturn V rocket was synthetic – it was not found 'as is', growing in a swamp or being ejected from a volcano ('You Only Live Twice' style). But the materials it was made from were all of natural origin, even if some of them may have been the result of considerable processing of naturally occurring materials.

Everything you see here is of natural origin (From 'You Only Live Twice', Eon Productions)

Any material thing in our world is of natural origin. Some materials are used much as found 'in nature', sometimes some cleaning or tidying is needed (think of natural diamonds being 'cut' to best reflect light), some purifying (separating compounds from crude oil fractions), some extracting (metal from ore), some synthesising (ammonia from hydrogen and nitrogen)… The amount of processing may vary considerably, but everything material that goes into a manufactured product is ultimately of natural origin.

So Herbal Essences products are 100% of natural origin, just as are the products of all their competitors.

A vague distinction

Webpages advertising specific Herbal Essences product lines often simply report that they are of 9n% natural origin, as in the examples below (95%, 96%, 97%). However, I found a page where it was clarified that the 90+% of natural origin included "purified water and ingredient materials derived from a natural source and subjected to limited processing".

So Herbal Essences do not use natural ditch water, or natural swamp water, or even natural sea water in their products, but rather purified water. I am pleased – as I have used Herbal Essences products, and will likely do so again, and I would rather not use dirty water when I am seeking to clean my hair.

Water – easily sourced from nature, and used in hair products (Image by mac231 from Pixabay)

So, it seems that for Herbal Essences, being of natural origin actually means, natural materials found in a suitable form to be used directly, or ("natural derived") only needing a "limited" amount of processing. Limited processing is a good thing in 'green chemistry' terms (less waste, less energy needed) but it is both a vague notion (who is to decide what makes the processing 'limited', and how does a consumer know what Herbal Essences count as limited?), and of course it is simply a quite different concept to being of natural origin.

I guess the company wanted a way of saying they were basing their products on natural products (such as plant extracts) without being misleading by implying that they could simply go and collect all the component materials and use them without needing any further processing. These materials may be pressed, steamed, or separated and purified in other ways, but are not generally the outcomes of complex synthetic processes. I can see both why that would be attractive to consumers, and why it is not easy to get across in a simple catchy term.

Yet the claim that 94% of your hair product is of natural origin, when a moment's thought should lead to the consumer realising that actually all products are of 100% natural origin, is a claim that (unlike the missing 6% of your Herbal Essences brand shampoo), does not have any substance.

a "limited" amount of processing

is both a vague notion and simply a quite different concept to

being of natural origin.

Appendix: Some examples of products that are not completely of natural origin

95% natural origin

The Herbal Essences Coconut Milk conditioner is, according to their website,

95% natural origin
73% purified water and 22% natural derived ingredients other 5% for a good usage experience & product stability.

https://herbalessences.co.uk/en-gb/products/coconut-milk/coconut-milk-shampoo/
96% natural origin

The Herbal Essences Coconut Milk conditioner is, according to their website

96% natural origin
88% purified water and 8% natural derived ingredients other 4% for a good usage experience & product stability.

https://herbalessences.co.uk/en-gb/products/coconut-milk/coconut-milk-conditioner/
96% natural origin

The Herbal Essences Bourbon & Manuka Honey shampoo, is,

96% natural origin
73% purified water and 23% natural derived ingredients other 4% for a good usage experience & product stability.

https://herbalessences.co.uk/en-gb/products/bourbon-manuka-honey/bourbon-manuka-honey-shampoo/
97% natural origin

Their Volumising White Strawberry & Sweet Mint shampoo, is

97% natural origin
84% purified water and 13% natural derived ingredients other 3% for a good usage experience & product stability.

https://herbalessences.co.uk/en-gb/products/white-strawberry-sweet-mint/white-strawberry-sweet-mint-shampoo/

At least 9/10ths natural origin

I learn from the company's website that

"All of our Herbal Essences bio:renew hair products have a 90% natural origin *"

https://herbalessences.co.uk/en-gb/whats-up-with-paraben-free-shampoo/

And they kindly explain that by natural origin they mean

"* includes purified water and ingredient materials derived from a natural source and subjected to limited processing"

Source cited:
  • Feyerabend, P. (2011) The Tyranny of Science. Cambridge: Polity Press

Footnote

1: All quotes are from the website pages cited as accessed on 22nd August 2021.

2. I note that Wikipedia suggests that

"Fruit waxing is the process of covering fruits (and, in some cases, vegetables) with artificial [sic] waxing material. Natural [sic] wax is removed first, usually by washing, followed by a coating of a biological or petroleum derived wax. Potentially allergenic proteins (peanut, soy, dairy, wheat) may be combined with shellac."