“Given Darwinism, even our cognitive faculties must be the result of natural selection. Every aspect of human brain physiology and psychology was entirely fixed by its survival value. This means that nowhere along the human evolutionary path did a concern for truth necessarily come into play. So long as an organism’s cognitive apparatus enables it to stay alive, its beliefs need not be true or even reasonable. There is no necessary connection between the survival potential of a cognitive system and the truth of the beliefs it produces...this means that if naturalism is true, then we have no reason to be confident that any of our beliefs are actually true, and that includes our belief in the truth of naturalism.”
As quoted by James Spiegel in The Making of an Atheist, p. 58-59
Think about it.