Tautology


A topic in Learners' conceptions and thinking


Tautology

Tautologies are circular arguments.

"For instance, if we defined 'fact' as 'that which fits a set of laws',
the principle 'Every fact is lawful' would become a tautology."

Mario Bunge

A form of pseudo-explanation?

Explanations constructed by learners sometimes have the superficial form of an explanation, but are deficient as scientific explanations. These constructions have been called 'pseudo-explanations', and are of various forms (Taber & Watts, 2000).

Read about pseudo-explanations


Tautology in everyday thought

The anthroplogist Evans-Pritchard reported how the Zande people explained the ability of their poson oracles to know about the covert action of witches,

"If you press a Zande to explain how the poison oracle can see far-off things he will say that its mbisimo, its soul, sees them. … In saying that the poison oracle has a mbisio Zande mean little more than 'it does something' or, as we would say, 'it is dynamic'. You ask them how it works and they reply , 'it has a soul'. If you were to ask them how they know it has a 'soul', they would reply that they know because it works. They are explaining mystical action by naming it. The word mbisimo describes and explains all action of a mystical order."

Evans-Pritchard, 1976 – emphasis added

We might consider:

  • You ask them how it works and they reply , 'it has a soul'.
  • If you were to ask them how they know it has a 'soul', they would reply that they know because it works.

We might see this as an example of tautology – circular thinking.


Tautology – by definition

Sometimes psuedoexplanations do not offer any deeper insight because of the ay we define terms. Consider this example (due to philosopher David Hume):

"But to convince us of this proposition, that where there is no property, there can be no injustice, it is only necessary to define the terms, and explain injustice to to be a violation of property."

If we define injustice in terms of prorpty rights, then we can explain that there can be no injustice in the absence of property, but this is little more than a rephrasing of the definition. (If we defined injustice in terms of a wider range of rights, then we would find injustce in situations not involving property.)

The biologist Ludwig Fleck posed what mighgt be called a pseudo-question, of why rivers always reach the sea:

"How does it come about that all rivers finally reach the sea, in spite of perhaps initially flowing in a wrong direction, taking roundabout ways, and generally meandering? There is no such thing as the sea as such. The area at the lowest level, the area where the waters actually collect is merely called the sea! Provided enough water flows in the rivers and field of gravity exists, all rivers must finally end up at the sea."

Fleck, 1935/1979

That is, given how we define 'river' and 'sea', rivers must reach the sea, because we call the bodies of water that rivers flow into sea.


Circular thinking

Some proposed explanations are circular as they assume what is to be exlpained. Sometimes this is obvious to anyone examining the explanation, and sometimes it becomes clear with a little analysis.

For example, consider this response when "Umar, an A level chemistry student (i.e. c.17 years old), was asked about the type of bonding in tetrachloromethane."(Umar was a participant in the Understanding Chemical Bonding project.)

"It's like polar, 'cause it's between ionic and covalent, 'cause it's somewhere in between, like the electrons might be pulled more strongly towards the chlorine than the carbon,'cause the chlorine's more electronegative."

Taber & Watts, 2000, p.341

This response has the form of an explanation constructed of a causal chain: "…because…because…because…". These kinds of explanations are common in science, and learning to build such explanatory chains is important for science students.

Read about a resource for constructing explanations in chemistry

However, the link "It's like polar, 'cause it's between ionic and covalent" does not really offer an explanatory connection, as 'between ionic and covalent' can be seen as another way of saying 'polar', so being between 'between ionic and covalent' rephrased, perhaps defines, but does not explain 'polar'.

"In the interview Umar was probed to see how much further his understanding might stretch, and in particular what he understood by 'electronegativity'. Umar reinterpreted his description of the
polar bonds in terms that the electrons would

"spend more time at the chlorine than the carbon",

and so this was followed up:

I: So why do they spend more time at the chlorine than the carbon?

U: 'Cause chlorine's more electronegative.

I: What does that mean?

U: It's got more tendency to attract an electron from another atom.

Taber & Watts, 2000, p.341

Again, if the chlorine being more electronegativeis is understood to mean electrons spending more time at the chlorine than the carbon, then answering the question "why do they spend more time at the chlorine than the carbon?" with "because chlorine is more electronegative" is in effect saying

the electrons spend more time at the chlorine than the carbon

because

[chlorine's more electronegative =] the electrons spend more time at the chlorine than the carbon

So, this is no more than a tautology.

The physicist Hermann von Helmholtz is quoted as saying that

"In nature, transformations always tend to proceed from less probably to more probable states."

Hermann von Helmholtz

One might suggests it is almost a truism that when a system in an unprobable state changes, it is more likely to end up in state more likely than its starting point,than in one even less likely. That is this might be a valuable insight – but could also be considered as necessarily so and therefore a tautology.


Taultology in public science discourse

As another example, an astrophysicist being interviewed on the radio seemed to suggest that scientists had estimated the number of stars in our galaxy as one hundred billion by counting 1% of the stars and scaling up. But this seems to require us to know what 1% of the number of stars is before we start counting. That is,

  • If we assume there are 100 billion, then we need to
  • count one billion, and then
  • multiply by 100 to give…
  • one hundred billion.

Clearly that would not work unless we had already estimated the number we are looking to estimate.

Read 'Counting both the bright and the very dim: What is 1% of a very large, unknown, number?'

Arguably, tautology was built into the ideological language ('newspeak') of the Soveit Union (parodied by George Orwell in 1984). Slava Gerovitch refers to how,

"…Marxism is correct because it is scientific;

Soviet science is correct because it is Marxist."

Gerovitch, 2004

Gerovitch quotes the following example:

"In a socialist society, a crisis of science is impossible…since Marxism – the ideology of socialism – is a scientific ideology and therefore, by its own nature, must be in harmony with the objective content of science."

Aleksandr Aleksandrov quoted in Gerovitch, 2004

Work cited:
  • Bunge, M. (1998). Philosophy of Science. Volume 1: From problem to theory. Routledge. (First published – 1967)
  • Evans-Pritchard, E. E. (1976) Witchcraft, Oracles, and Magic among the Azande. Abridged with an introduction by Eva Gillies. Clarendon Press. Oxford
  • Fleck, Ludwik 1935/1979 Genesis and Development of a Scientific Fact (Entstehung und Entwicklung einer wissenschaftlichen Tatsache: Einführung in die Lehre vom Denkstil und Denkkollekti) (Thaddeus J. Trenn & Robert K. Merton, Eds.) (Tr. Fred Bradley & Thaddeus J. Trenn) Chicago & London: The University of Chicago Press
  • Gerovitch, S. (2004) From Newspeak to Cyberspeak. A history of Soviet cybernetics. MIT Press.
  • Taber, K. S. & Watts, M. (2000) Learners' explanations for chemical phenomena, Chemistry Education: Research and Practice in Europe, 1 (3), pp.329-353. [Free access]