KP: Further, human beings would be most unfortunate if in fact a theory as important as PRM (the physical realization of the mental-VR) were true and could not be rationally believed. Goetz and Taliafero appear to concede that PRM could be true, but they hold that the truth of PRM would preclude rationally believing it by our standards of rational belief. However, if our standards of rational belief are such that they can preclude us from rationally believing an important theory that (we are assuming) is in fact true, then perhaps our standards of rational belief are deficient. Standards of rational belief are supposed to permit, not preclude, rational belief in true theories. If PRM is true—and, again, Goetz and Taliafero apparently concede that it could be—then this is a very important truth and there needs to be some way that we can rationally believe that it is true.
VR: Interestingly, if it is problematic that certain things of significance my be true, and yet we are unable to rationally believe them, then this poses some problems for a number of interesting positions in philosophy, which many religious skeptics endorse. A good example would be Hume's essay on miracles. If we take Humeanism about miracles far enough, the God could be sitting up in heaven performing miracle after miracle, and the best we could, as human reasoners, could say about it would be that we don't have a naturalistic explanation for it yet. Water into wine? We'll understand it better by and by. Someone rises from the dead? It's GOT to be a hallucination. I'm being appeared to hellishly? Got to be an undigested bit of beef, a blot of mustard, a crumb of cheese, a fragment of an underdone potato.
Are there features of the world and human minds that are necessary in order for there to be, for example, any scientists in the world? Suppose reality were nothing but a turnip with a bit of whipped cream on top. If this were the case, this would be a significant truth, but given the nature of knowledge, neither the turnip nor the whipped cream would know this. Turnips and bits of whipped cream don't do science. Is this a problem?