Noam Chomsky Vs David Deutsch

1. Their Fundamental Disagreement About the Reach of Explanatory Power

Chomsky insists that humans, as biological creatures and not angels, must have cognitive limits just as any other biological creature. He illustrates this point by the example of a rat’s inability to solve a prime number maze with however much training. He then concludes that there might be martials somewhere in the universe who are as superior to us as we’re superior to rats. Deutsch would say this is a mistake. He thinks there are only two levels of cognition (computation), namely, non-universal and universal. He says that you are either in the first (like rats) or in the later (like humans and Turing machines) and that if you are in the later then there is, even in principle, no further level of cognition that is beyond your reach. So, he insists there is no concept we can fail to understand or problem we are in principle unable to solve, given the key to solving the problem is only limited by our understanding and not by some law of physics, in which case no other thinking being can solve it either.

The former’s disagreement with the latter’s idea of infinite reach of explanation is I think in odds with his conception of the unbounded nature of language. He’s failing to see that it is this very property of language that also makes limitless understanding possible. But perhaps these two infinities aren’t necessarily in odds, Chomsky seems to think that within the bounds of our capacity, we can create infinitely many ideas, but that this infinity is still a bounded infinity and that there is no guarantee that our infinite creativity enables us to understand everything there is to understand in the universe without bound. This isn’t an unconceivable idea, after all, some infinities are bigger than other infinities (I no longer take this specific line to be true). Deutsch concedes that this realm of unreachable understanding is not unconceivable but thinks that this argument is in the same class of bad explanations as believing in the supernatural. It is, by definition, impossible to disprove the existence of such horizon of intelligibility, but there is a mistake to be corrected in the attempts made to argue for it. The mistake is when Chomsky uses an example of a mice’s inability to understand prime number mazes or similar examples as evidence for possible limits existing for all biological beings. The mistake is in the failure to recognize that non-humans and humans have a qualitative difference in their capacity to understand, namely the fact that one is a universal computer and the others aren’t. One evidence for this that should have been immediately apparent for Chomsky is our capacity for language, which is unique to us in the animal world. And hence these kinds of examples simply say nothing about whether or not we have limits. His other arguments in this regard are even worse. Like his idea that problems we find challenging like chess or our slow progress in certain fields like cognitive science may be hints into where our limits lie. These examples miss the point entirely, let me explain.

Let me start with the chess example and how it isn’t an indication of our limitations at all. There is no concept that isn’t understood in chess, it is a completely understood subject by humans. We know what it takes to win, and better performing humans or robots that will come in the future won’t come because of additional fundamental understanding of chess, they will only come because of improvements in optimization techniques or hardware improvements. New fundamental concepts in chess weren’t what constituted our ability to build programs that perform significantly better than us. This means that the chess problem is only a hardware problem, i.e., memory and speed. If the argument was that we have limits in those areas, then there is no doubt about it. But these hardware constraints never jump over to areas of understanding or grasp. Whatever the program understands, we can understand too. It just does it more efficiently because of its hardware. And any other similar example can’t possibly be an argument for the existence of such a horizon beyond which we don’t even have the concepts for. Because the stuff of understanding (or science-forming-ability as Chomsky puts it) doesn’t come from memory and speed, it comes from creativity and creativity is not bounded. Arguments against this unboundedness can’t possibly come from areas that already lie in our repertoire of explanations (like the chess example). Similarly, our failed or relatively slow progress in areas like cognitive science aren’t any indication into our limits, they just mean we are mistaken in our approach. So, that’s why Deutsch is right in saying that there is no rational argument in support of this idea, because there is no evidence of our limit within concepts we already grasp, and if you invoke stuff beyond our limits to explain or argue for our limits, then that’s just the same as believing in the supernatural, which is irrational (even if you can’t disprove it!).

2. Difference in Theories of the Origin of Creativity

Chomsky thinks that the creation of language and creativity happened around the same time and that this is the difference between us and other species. What Deutsch thinks in this regard is not very clear. But he does not draw this direct line between language and creativity. He gives emphasis to memes (copyable ideas) as a crucial piece in the development of explanatory power. He said explanatory power dates back to pre Homo Sapiens. He said, “I believe species before homo sapiens also had explanatory power, also our cousin species like Neanderthals”. Also said, “my heterodox theory about this is that this ability came about because of the need to pass on cultural knowledge/memes”. His idea is that because memes can evolve much faster than genes, which is the biological default knowledge propagator, this opened the door for rapid progress. But he acknowledges that these memes aren’t enough to explain explanatory knowledge. He explains the further leap needed by saying, “our ancestors used memes and at some point, greatly increased their memory, but then they also evolved creativity”. So, there isn’t any real conflict between their ideas here because they both attribute our distinguishing factor to creativity. Deutsch mentions that other species like chimps also have memes, so this can’t be what sets us apart. The only difference in their ideas maybe that Chomsky attributes our distinguishing ability to the emergence of creativity and/or language alone, while Deutsch muddles this idea with the, in my view unnecessary, invocation of cultural knowledge/memes. Another point where Chomsky might have a problem with is the phrase “they also evolved creativity”, because Chomsky insists that creativity couldn’t have evolved like, for example, organs evolved, i.e., incrementally. He insists that you can’t go from finite to infinite (which is what creativity is) incrementally, and so it most likely was a mutation which then propagated. There was no natural selection process that incrementally developed creativity/language. They might also disagree about the timeline of the emergence of creativity because Chomsky definitely disagrees with the idea that Neanderthals also had explanatory power/creativity.

Edit:

It is possible that I may have misinterpreted Deutsch’s position entirely. The idea that creativity came about as a mutation in a single individual is not controversial, because the source of all divergence in evolution is mutation in an individual. What Deutsch is interested in is why this mutation replicated itself successfully enough so as to survive and be found in all Homo Sapiens today. The idea that this happened through natural selection is also not controversial, because all evolution is a process of natural selection. What Deutsch is primarily interested in is what the selection advantage of creativity was in those times, since creativity wasn’t used immediately after its emergence in applications like tool making. In fact, creative problem solving was so rare for almost the entirety of the species’ existence. This is why stasis was the norm for humans for a very long time. But if this is so, then what was the advantage of keeping this gene that was responsible for creativity that made it get selected for? He answers this question with the idea of memes, he says that since humans and other pre-humans were already practicing meme copying, the individuals who had now newly acquired creativity were able to copy memes much more effectively, and hence they survived, and the others didn’t.

But I think Chomsky would have a beef even with this idea. He seems to be against any arguments that suggest that the emergence of language, which he uses as a surrogate for creativity, evolved because of cultural reasons. I also don’t think he believes that creativity was never put to practical use immediately after its emergence, because he often links the time when language emerged to the time when cave dwellers first started to exercise art, for example, by panting on walls. And if this is true then it’s not hard to imagine why creativity would be selected for, rendering the idea of memes irrelevant. But this difference in idea is a relatively easy one to solve because it’s just a matter of looking at the archeological evidences we have.