You’ve argued that if the materialistic view were correct, then our cognitive faculties would have developed solely to maximize the chances of gene transmission, not to maximize truth.  In this case we would have no reason to think that our reasoning is reliable, and so we would have no reason to think that any view (including the materialistic view) is correct.  But if materialism is not correct, then we don’t have this problem.

I agree with you that we are justified in relying on our faculties without being able to show that they are justified, but I have doubts about this bit of reasoning.  As you know, C.S. Lewis proposed it, and Alvin Plantinga has been pushing something like it for a long time, but here’s my problem.  Let us suppose that we are hard-wired to get things wrong sometimes.  Then yes, perhaps the reasoning that leads us to believe in naturalism is infected in this way.  But these suppositions are still not enough to get the conclusion that we can’t trust the reasoning that led us to believe in materialism.  We need, in addition, an argument to show that the reasoning for materialism is of just the sort that our evolutionary heritage makes problematic.



I see your point, but if we really were hard-wired to get things wrong sometimes, then I don’t think your suggestion would get the materialist off the hook.  You say that all he would need is an argument, P, to show that his argument for materialism, M, is not vitiated by how we are wired.  But then wouldn’t he also need an argument, Q, to show that his argument P is not vitiated by it either?  He would merely have embarked on an endless regress.

As I see the matter, unless we can already be sure that we know something, we aren’t in a position to criticize the faculties by which we know them.  For this reason, a classical thinker – say, Aristotle or Thomas Aquinas -- doesn’t demand a critique of the power to know anything before we concede that we know something.  Instead he begins by asking, “Granted that we do know something, what must the universe be like for this to be the case?”  And it turns out to contain not just matter but other things too.

But the materialist holds that nothing is real but matter.  So he has to ask a different question:  “What reason have I to trust my faculties if materialism is true?”  And it turns out that he hasn’t any.  So although a classical thinker is justified in relying on his faculties without being able to show that they are justified, a materialist who makes such a claim for himself is trying to have his cake and eat it.