Our individual beliefs are not adaptations. Our disposition to acquire beliefs is.
Since our disposition to acquire beliefs is an adaptation, it is advantageous. And it is advantageous because its products, beliefs, are advantageous.
Nonetheless, it is not a disposition to acquire beliefs because they possess the property of being advantageous. It could not be, because the property of being advantageous is not detectable until the consequences of acquiring a belief manifest themselves and that is not typically at the time the belief is acquired but afterward, sometimes long afterward.
The disposition to acquire beliefs must therefore be a disposition to acquire beliefs that possess a property that can function as a surrogate or proxy for the property of being advantageous.
The only plausible candidate for the surrogate or proxy is the property of being true, where the property of being true is the property of corresponding (in some way) to the state of affairs the belief is about. It is obviously the case that we have a disposition to acquire beliefs. Therefore, not only is there such a thing as truth but also the correspondence theory of truth is true.
This was negatively inspired by Plantinga's argument against naturalism. His error was to proceed as though beliefs themselves were adaptations. Furthermore, his alternative is vacuous. How can we know that our beliefs are true, he asks. His answer is that there is a being with the power and desire to bring it about that we can know it. But that does not tell us anything more than that we can because we can.
The same argument is an argument against pragmatism. The only way to argue against it is to posit a surrogate property that can compete with truth. Appeals to advantageousness do not work.
Copyright Brian Zamulinski.