The mind-body problem is not just a local problem within the human person. Rather, the answers to this question are analogous to the entire cosmos. Nagel asks, “Can a Darwinian naturalist account explain the phenomenon of mind, consciousness, reason and value?” Can we integrate the concept of “Mind” within a modern outlook (Nagel 8)?
He states the problem: whatever explains the existence of organisms must also explain the existence of mind (14). Most of the book is a survey of how Neo-Darwinian Naturalism fails to explain “why” and the like. Throughout he echoes challenges by Plantinga and others: “If two faculties in us are both natural, why should we privilege our belief-forming mechanism to correct other cognitive faculties” (28). He doesn’t say it here (though he does later), this is the problem of value. How does a purely natural account posed in the problem above explain value-judgments?
His section on consciousness was a bit weaker. He argues that naturalism can’t account for mental phenomena that is evident from the first person inner point-of-view of the conscious subject (38). I agree but I don’t think Nagel gives the strongest argument. For a better treatment consult Moreland and Swinburne, especially the latter’s Evolution of the Soul. especially the latter’s Evolution of the Soul.
Nagel does advance the following argument:
Let Ψ = a mental event
Let φ = a physical event
On the naturalist account Ψ = φ . But here is Nagel’s problem with it: what is it about φ that makes it also Ψ ? Nagel says it must be some property conceptually distinct from the physical properties that define φ. In other words, if you look at a mental state like a sensation (or intention or the like). It can’t simply be the same as a physical event. It will always be (φx), where x is the perspective of the thinking agent. If that’s the case, then Ψ =/= φx.
What Nagel needs is something like Leibniz’s law of the Identity of Indiscernibles:
For any x, and for any y, if they are identical to each other, then for any property P, P will be true of x iff P is true of y. And if they aren’t identical, then they aren’t the same thing.
*Nagel says substance dualism leaves biology with many unanswerable questions (49n12). So what if it does? If Nagel holds to this criticism, then it’s hard to see exactly how his position differs from naturalism at the end of the day.
* As critics have noted, Nagel rejects naturalism but he also rejects theism of any form (and with it, mind-body dualism). As such, he hasn’t given us anything resembling a coherent alternative. It’s like he is a naturalist gadfly. By still insisting on a biological/physical account of everything, he hasn’t really moved beyond naturalism–certainly he hasn’t moved beyond it given that he also rejects theism.
Nagel has advanced important criticisms of naturalism. One hopes that the Regime will take these criticisms seriously and remove naturalism from its vaunted pedestal where it is politically immune to any criticism. With that said, Nagel offers nothing in terms of an alternative.