The EAAN, or Evolutionary Argument Against Naturalism, is an argument by Plantinga. The Wikipedia entry provides a reasonable summary.
In a recent post at the Uncommon Descent blog, Barry Arrington gives an argument based on the EAAN. This will mostly be a response to Arrington.
What is the EAAN?
Here’s a short quote from the Wikipedia article.
The EAAN argues that the combined belief in both evolutionary theory and naturalism is epistemically self-defeating. The reason for this is that if both evolution and naturalism are true, then the probability of having reliable cognitive faculties are low.
Personally, I’m inclined to see the EAAN as a reductio ad absurdum of a traditional account of epistemology. Traditionally, it is said that knowledge is justified true belief. I’ve disagreed with that in the past, and I continue to disagree.
That Wikipedia quote talks of both evolution and naturalism as being true. I have never subscribed to naturalism (nor to materialism), because I don’t know what it would mean to say that naturalism is true. And evolution, as used in that quote, refers to the theory of evolution. I tend to think of scientific theories as neither true nor false. Rather, I see a theory as a set of pragmatic conventions that provide a guide to how we should talk about the world. As such a framework, the theory sets standards, in this case for biology and related fields. Those standards give as ways of coming up with factual (true) statements about reality. But whether or not we see the theory as true does not seem important.