Alvin Plantinga makes a philosophical assault on Darwinism, claiming that it is self-undermining. Suppose the Darwinian theory of evolution were true. Then, Plantinga submits, our mental machinery, having developed from that of lower animals, would be highly unreliable when it came to generating true theories. (As it happens, Darwin himself once confessed to the same ''horrid doubt'' about his theory in a letter: ''Would anyone trust in the convictions of a monkey's mind?'') In other words, if our belief in Darwinism were true, then none of our theoretical beliefs would be reliable -- including our belief in Darwinism. Theism, by contrast, escapes this difficulty: if we are made in the image of God, the ultimate knower, then divine providence can be counted on to have supplied us with reliable cognitive faculties.Ah, but many creationists on these threads have claimed that we are "fallen" - all human imperfections are explained by The Fall. Therefore, any inabilities we may have are explained by Original Sin. So Plantinga's argument fails.
Even beings with perfect mental function would not be omniscient, and would still be subject to the same fundamental limitations regarding what can be known/proven.