The reasons for reason
Gene Callahan is going back and forth with economist Brad DeLong about philosopher Thomas Nagel’s recent book in which Nagel argues (or so I gather–I haven’t read it) that a strictly materialist understanding of evolution is insufficient to account for the human mind’s ability to understand reality.
While I haven’t read Nagel’s most recent book, I have read his The Last Word, and it seems that he’s developing the argument he made in that earlier work, particularly the last chapter. Gene is certainly right that Nagel is a philosopher of the first rank, and anyone who dismisses him as “dumb” is being dumb himself. (Though, again, I can’t vouch for his most recent work.)
Nagel’s argument–or arguments similar to it–has a long pedigree in the history of philosophy, arguably going all the way back to Plato and Aristotle. There has always been something seemingly mysterious about the fact that the human mind is able to understand reality. More specifically, that it can–apparently–understand at least parts of the “deep structure” of the physical world, such as the laws that govern its behavior. And that these laws themselves can be expressed in mathematical form. We might put the mystery this way: How can a trait emerging from a “jumped-up primate” (to use DeLong’s expression) have the kind of universal validity that we claim for reason?
These kinds of considerations have led many philosophers to conclude that there must be some deep affinity between the human mind and the cosmos. One variation of this conclusion is that the human mind reflects, albeit in a limited way, the mind of God and that this is why our reason is able to uncover, to some extent, the rational order of the universe.
By contrast, on the supposition that our rational faculties were formed solely by the blind evolutionary pressure to survive, it’s hard to see why we should expect that they would be capable of unlocking the secrets of the universe. I say, “it’s hard to see” not “it’s impossible to see” because I’ve always been uncertain just how much these considerations actually show, rather than being somewhat suggestive. In my view, a deflationary, “Humean” account of reason is inconsistent with the truth-claims usually made on behalf of science (particularly by good secular liberals); but that doesn’t mean that a more robust, yet still naturalistic, account of reason isn’t possible.