Friday, December 16, 2011

Knowing

In an interview at Christianity Today about his new book Alvin Plantinga argues that there is no real reason to believe religion and science are incompatible but he does think "naturalism" and science are.
In the last, much briefer section of the book, you discuss whether there is a fundamental incompatibility between naturalism and the theory of evolution.

I think that's an extremely interesting and important point, though to argue for it properly is quite complicated; it's hard to do in a brief compass. The basic idea, which is far from being original, is that if you are a naturalist and think that we have come to be by evolutionary processes, then you will think that the main purpose of our cognitive processes, our mental faculties, is survival and reproductive fitness, not the production of true belief. Evolution doesn't give a rip about whether your beliefs are true. It only cares whether or not your actions are adaptive, whether they contribute to your fitness. From the point of view of evolution together with naturalism, you wouldn't expect that our faculties would be really adjusted to truth or aimed at truth. They would just be aimed at fitness.

But if this is true, if our minds are aimed at mere survival, not at truth, then it's not probable that our minds should be reliable—that is, produce an appropriate preponderance of true over false beliefs; and if that is so, then one who believes both naturalism and evolution should reject the thought that our minds are reliable. But that's a crippling position to be in. Nietzsche is among the people who have suggested this problem. Some contemporary philosophers—Thomas Nagel, for example—have voiced the same worry, and so did Darwin himself. [more]
C.S. Lewis made a similar argument in Chapter 3 of Miracles, parts of which are quoted here, including this:
"…a strict materialism refutes itself for the reason given long ago by Professor Haldane: 'If my mental processes are determined wholly by the motions of atoms in my brain, I have no reason to suppose that my beliefs are true . . . and hence I have no reason for supposing my brain to be composed of atoms.’ (Possible Worlds, p. 209 […] [Naturalism] offers what professes to be a full account of our mental behaviour; but this account, on inspection, leaves no room for the acts of knowing or insight on which the whole value of our thinking, as a means to truth, depends.[…] It is agreed on all hands that reason, and even sentience, and life itself are late comers in Nature. If there is nothing but Nature, therefore, reason must have come into existence by a historical process. And of course, for the Naturalist, this process was not designed to produce a mental behaviour that can find truth. There was no Designer; and indeed, until there were thinkers, there was no truth or falsehood. The type of mental behaviour we now call rational thinking or inference must therefore have been 'evolved' by natural selection, by the gradual weeding out of types less fitted to survive." .... [more]