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[last updated 1 Jan 2007]

Chomsky's (mis)understanding of human thinking

1. introduction

Chomsky founded and leads the psycholinguistics field, and is the most important figure in this field. Not only that, he also has a strong status outside psycholinguistics, and many people, including many scientists, believe he made a large contribution to our understanding of human thinking.

In the other related texts I discuss why psycholinguistics is nonsense, but Chomsky's nonsense goes even deeper than this, and here I give examples of Chomsky's ideas outside linguistics.

If I have read the quotations below as quotations, my respond would be: "Something is wrong here. You cannot reach the status Chomsky achieved if you think such a nonsense. These are probably misquotations, distorted and out of context." Well, they are not. However, I would expect some of the readers not to believe it. If you are one of these readers, I highly recommend that you read the original.

All the quotation in this text, except one, are from

Noam Chomsky (1988). Language and the problems of knowledge. MIT Press. ISBN 0-262-03133-7.

I put in bold face the important parts of the quotation, but otherwise did not edit them at all.

2. Science

Here is what Chomsky has to say about science (P. 157-158): "This partial congruence between the truth about the world and what the human science-forming capacity produces at a given moment yields science. Notice that it is just blind luck if the human science-forming capacity, a particular component of the human biological endowment, happens to yield a result that conforms more or less to the truth about the world."

You probably have to read this more than once to actually understand it. Chomsky claims that the achievements of science are "blind luck". To make clear that isn't a 'slip of the pen', Chomsky repeats this claim in the next page (P.158): "The experience that shaped the course of evolution offers no hint of the problems to be faced in the sciences, and ability to solve these problems could hardly been a factor in evolution. We cannot appeal to this deux ex machine to explain the convergence of our ideas and the truth about the world. Rather, it is largely a lucky accident that there is such a (partial) convergent, so it seems."

Chomsky opinion is based on the argument in the last quote (at least in this book), which argues against evolution of the science-forming capacity. This 'argument', however, is nonsense, because it is based on the assumption that science is based on 'science-forming capacity, a particular component of the human biological endowment' {1}. Chomsky hasn't realized yet that humans has a general intelligence, which they can use in various areas, including science.

This refusal to admit a general intelligence is a fundamental error in Chomsky's thinking. In this book it is simply taken for granted that general intelligence does not exist, but in other places Chomsky 'argues' against it (e.g. 'Challenging Chomsky', Rudolf Botha (1989) ISBN 0-631-18027-3, P.30-31). The 'argument' is based on stating that supporters of general intelligence cannot say on what principle it is based. This is nonsense, because the existence of general intelligence is not dependent on whether we understand its underlying principles or not.

3. Arithmetical ability

On arithmetical ability, Chomsky says (P. 167):

"Take the human number faculty. Children have the capacity to acquire the number system. They can learn to count and somehow know that it is possible to continue to add one indefinitely. They can also readily acquire the technique of arithmetical calculation. If a child did not already know that it is possible to add one indefinitely, it could never learn this fact. Rather, taught the numerals 1, 2, 3, etc., up to some number n, it would assume that that is the end of the story."

Again, you probably need to read the last two sentences more than once to comprehend what they actually say. Chomsky does not bother to tell us why would the child assume it is the end of the story, and does not base this statement on supporting evidence. He also completely ignores the question of what will happen if the child is told that you can add one indefinitely. We have to guess how Chomsky reached the last two statements, but the guess is easy. This is an extreme case of his disbelief in general intelligence, which leads chomsky to believe that humans cannot learn anything.

If human cannot learn even this simple fact (counting to infinity), then how do they know anything at all? Chomsky's answer is simple: it is built-in in our 'biological endowment', like the 'science-forming capacity'. Chomsky, in agreement with most of the rest of the researchers, realizes that this 'number faculty' could not evolve, because there was no selective pressure for it (P. 168): "How did the number faculty develop? It is impossible to believe that it was specifically selected." The divergent is in the explanations: other researchers simply assume it is learned, but Chomsky cannot accept this.

Instead, he states, without any hint of evidence, that (P. 168)"In fact, the capacity was latent and unused throughout almost all human history." He continues with an amusing maneuver (P.169): "At this point one can only speculate, but it is possible that the number faculty developed as a by-product of the language faculty." The advantage of this tactics is that it brings Chomsky back to linguistics, where he is supposed to be an expert. That this is obvious nonsense, because human language is very non-mathematical in its nature, is not really relevant as far as Chomsky is concerned.

4. General knowledge

The discussion about general knowledge is much more diffused. It is based to a large extent on the 'lack of relevant experience'. Chomsky descends to general knowledge from linguistics discussion, e.g. (P. 28):

"Consider a simple word such libro. Without instruction or relevant experience, each speaker of Spanish knows that this word can receive either an abstract or a concrete interpretation."

Chomsky does not tell us what is the 'relevant experience' that the Spanish speaker is missing, so we have to guess. it seems most likely that this experience would be hearing the word libro used with abstract interpretation or with concrete interpretation. That would mean that Chomsky claims that Spanish speakers know how to use the word libro before they have heard it being used. That is such a nonsense that it is hard to believe that even Chomsky thinks it is true, but there does not seems to be any better interpretation.

This kind of argument continues for two pages, with the last example being (P.30): " I gazed at the elephant's trunk, which was packed full of clothes." The comment on this example is that "we understand the phrase elephant's trunk to refer to the elephant's luggage container".

From this, Chomsky continues: "The facts are known without relevant experience, and they need not be taught to a person learning Spanish or English as a second language." Again, what is the 'relevant experience' that the person is missing? Chomsky does not tell us, and there doesn't seems to be any interpretation of this term which does not make the quotation a straightforward nonsense.

Chomsky continues in the same paragraph (P. 28): "Evidently, the facts come to be known on the basis of biological endowment that is prior to any experience and that enters into determining the meaning of words with remarkable precision and surely not in any way that is logically necessary."

Hence, Chomsky believes that the fact that libro can be abstract or concrete, or that the elephant's trunk in the quote above is his luggage container, is based on biological endowment. Chomsky does not tell us here what is the biological endowment that can tell us these facts.

Up to here, the biological knowledge is of linguistic nature, but now Chomsky starts to expand. on the bottom of P.30 he adds the concept of namable things: ".. for example, the concept of namable thing, which turns out to have remarkable intricacies, even involving the sophisticated idea of human agency, when one investigates it closely". This is quite amusing, because normally people regard everything that can be discriminated as 'namable thing', i.e. they don't have the concept of 'namable thing' as such. Thus this concept is an invention, and hence can have any intricacies its inventor would like to give it.

On the top of P.31 Chomsky adds the concept of person. Studies of children show clearly that they learn this concept gradually, which is compatible both with learning from scratch and with acquisition based on innate guidance. Then Chomsky present his argument for the innateness of these concepts: "Surely none of this is learned through experience." (this is all the argument).

On the next page Chomsky makes clear how broad his assumption about 'biological endowment' is (P.32): "The child approaches language with an intuitive understanding of such concept as physical object, human intention, volition, causation, goal and so on." Apart from the word 'intuitive', this statement may be quite widely agreed. The question, however, is where this understanding comes from. The text on the previous pages, and the using the word intuitive, makes it clear that Chomsky means that this understanding is coming from 'biological endowment', rather than learned.

The problem with this assumption is that physical objects vary a lot in their attributes, and in the environment of a child in modern society, most of them have not existed long enough to affect evolution. Hence, the understanding of physical objects cannot be based on evolution. For most of people that necessarily means that this understanding is learned, but not for Chomsky. As we saw above, he believes that scientific understanding is 'blind luck', so presumably a child understanding of his fire-engine toy can also be a 'blind luck'.

This point is clarified later in the same paragraph (P.32): "The extent to which this framework can be modified by experience and varying cultural contexts is a matter of debate, but it is beyond question that acquisition of vocabulary is guided by a rich and invariant conceptual system, which is prior to any experience. The same is true even for the technical concepts of natural sciences, which the scientist acquires on the basis of only partial information and evidence, a good deal simply being taken for granted, without explicit or precise expression, except at the higher reaches of the sophisticated mathematical sciences."

Since it is 'beyond question', Chomsky does not give any argument for an 'invariant conceptual system, which is prior to any experience', but from the previous discussion the answer is clear. Chomsky does not believe in general intelligence, or in other words in the ability to learn novel concepts, and therefore must believe that concepts are never really novel.

In the second sentence of the last quote Chomsky displays again his contempt for science, and in a way that is clearly nonsense. The 'good deal' that is 'simply being taken for granted' is presumably based on the 'invariant conceptual system' of the previous sentence. However, what scientists take for granted is variant, and is, in general, based on evidence. It is true that in many cases scientists take for granted things they should not (see in Reasoning errors for examples in cognitive psychology), but these are mistakes, not the way science works in principle.

5. On neurophysiology

Even Chomsky realizes that it is the brain that does the thinking, and that the brain is made of neurons and neuroglia. Thus sciences of neurons, neuroglia and brain anatomy, collectively called neurophysiology, are important in understanding human thinking.

Not according to Chomsky. Here is what he has to say in a newer book

(Chomsky (1993). Language and Thought. Moyer Bell, 1-55921-074-5)
(P. 85):

"In fact, the belief that neurophysiology is even relevant to the functioning of the mind is just a hypothesis. Who knows if we're looking at the right aspect of the brain at all. Maybe there are other aspects of the brain that nobody has even dreamt of looking at yet.".

Thus Chomsky can dismiss complete fields of science as 'just a hypothesis'. Note that what Chomsky is dismissing is not specific theories inside neurophysiology, but the whole field, and that it is not based on any evidence to contradict the fundamental tenets of neurophysiology. It is based on the possibility of 'other aspects of the brain', but Chomsky does not tell us how these 'other aspects' could have escaped years of scrutiny by invasive methods in both animals and humans patients.

Dismissing whole sciences without evidence may seem outrageous, but it follows directly from Chomsky ideas about science. If science is 'blind luck', then neurophysiology can be simply a bad draw.

There is special significance for dismissing neurophysiology, because while Chomsky's ideas can be easily shown to be nonsense, they can be totally refuted (or confirmed) only by neurophysiological evidence. Thus by dismissing neurophysiology as 'a hypothesis', Chomsky protects his ideas from refutation.

6. Conclusion

Chomsky believes that learning of novel concepts is impossible, and hence that everything must be built in, as part of human 'biological endowment'. This applies not only to language, but to everything, including general knowledge about the world, numerical ability and science inquiry ('blind luck').

The amazing thing about these statements is not that Chomsky states them, as many people state all kinds of nonsense. The amazing thing is that after stating these, he is still regarded seriously by any intelligent person. In particular, considering his contempt to science, it seems surprising that serious scientists regard him as an authority.


[24Nov2002] The latest from Chomsky is an article in the last Science ( (Science, Volume 298, Number 5598, Issue of 22 Nov 2002, pp. 1569-1579). It is obvious that the point of this article is to establish the existence of "Faculty of Language", as opposed to language ability being based on general intelligence. It achieves its target by simply completely ignoring the other possibility. It is interesting how does such blunt demagoguery find its way into Science.



{1} Amusingly, when Chomsky argues against the evolution of the biological science-forming capacity (P.158), he mentions Peirce as the developer of the idea. Peirce did talk about evolution, but a non-biological one, in which inheritance, mutation and selection of ideas are a result of people transferring, modifying and judging ideas. Chomsky misinterprets Peirce, presumably because he cannot perceive the concept of non-biological evolution of ideas.


Yehouda Harpaz