Tuesday, May 31, 2011
Coyne on intentionality
Biologist Jerry Coyne responds to a recent post by Vincent Torley on the topic of whether the brain is a kind of computer. Torley had cited me in defense of the claim that the intentionality or “meaningfulness” of our thoughts cannot be explained in materialist terms. Coyne responds as follows:
I’ll leave this one to the philosophers, except to say that “meaning” seem [sic] to pose no problem, either physically or evolutionarily, to me: our brain-modules have evolved to make sense of what we take in from the environment.
The fallacy Coyne commits here should be cringe-makingly obvious to anyone who’s taken a philosophy of mind course. Coyne “explains” intentionality by telling us that “brain-modules” have evolved to “make sense” of our environment. But to “make sense” of something is, of course, to apply concepts to it, to affirm certain propositions about it, and so forth. In other words, the capacity to “make sense” of something itself presupposes meaning or intentionality. Hence, if what Coyne means to say is that an individual “brain-module” operating at the subpersonal level “makes sense” of some aspect of the environment, then his position is just a textbook instance of the homunculus fallacy: It amounts to the claim that we have intentionality because our parts have intentionality, which merely relocates the problem rather than solving it. If instead what Coyne means is that the collection of “brain-modules” operating together constitute a mind which “makes sense” of the environment, then he has put forward a tautology – the brain manifests intentionality by virtue of “making sense” of the world, where to “make sense” is to manifest intentionality. Either way, he has explained nothing.
Already deep in a hole, Coyne keeps digging:
And that’s not unique to us: primates surely have a sense of “meaning” that they derive from information processed from the environment, and we can extend this all the way back, in ever more rudimentary form, to protozoans.
Different formulation, same problem. To “have a sense of ‘meaning’” presupposes intentionality and is therefore hardly a notion to which one can coherently appeal in order to explain intentionality. “Information,” if meant in the ordinary semantic sense, also presupposes intentionality, in which case appeals to it in this context also explain nothing. If meant instead in the technical, non-semantic Claude Shannon sense, “information” does not presuppose intentionality, but it does not explain intentionality either, since Shannonian information theory is concerned with the transmission of information in the ordinary, semantic sense, not with its origin.
So, as I have said, Coyne has explained nothing at all, nor even gestured at a genuine explanation. True, his remarks were made in the informal context of a blog post; but if one is going to aver confidently that “’meaning’… pose[s] no problem,” he had better give at least some evidence of knowing what the philosophical problem of meaning or intentionality is and what philosophers have said about it. Coyne, like too many other contemporary scientists – and unlike their more accomplished but less arrogant forebears (Einstein, Schrödinger, Heisenberg, et al.) – seems to think his scientific competence excuses him from having to do his homework in philosophy before commenting on the subject. Nor is this his first offense.
The folks who hang out in Coyne’s combox seem even less well-informed than he is, if that is possible. (One of them apparently thinks I’m an ID theorist – looks like he didn’t get the memo.) So I suppose I need to point out for them that the issue has nothing essentially to do with religion, with “magic,” or with any of the other straw men and red herrings they’ve been furiously dissecting. But when you “already know” the other side is wrong, what’s the point of finding out what it really thinks, right?