So the pace, at which human minds have evolved over the last half million years and more recently the last 200,000 years, has been so frighteningly rapid that the evolution of cognitive function and perception can only occur in a small number of genes. If one needed to adapt dozens of genes changes in concert, in order to acquire the penetrating minds that we now have, which our ancestors 5,000 years ago didn't have, the evolution could not have taken place, it could not have occurred so quickly. And for that reason alone, one begins to really suspect that the genetic differences between people who lived 5,000 years ago is evidence that the difference between their cognitive functions and ours is not actually as large. Therefore, a rather small number of genes may be responsible for the powerful minds that humans have which most of us now possess.