If a male animal is prepared to attempt rape on occasion, then he is more likely to reproduce than otherwise. It has no existence beyond this, and any deeper meaning is illusory. They have their own coherent system of morality. On the atheistic view, I can t think of any reason why human beings should be regarded as the source of all objective moral value. Extraterrestrials do it.
Animals do it.
It s biologically advantageous. On the atheistic view, I can see no answer to that question. We may have the feelings as human beings that rape is wrong, but on the standpoint of the modern evolutionist, this is simply a biological-adaptation mechanism inculcated into us by millions of years of biological and social evolution. There is no reason to regard these values as absolutely right and wrong. And thus it seems to me that it is not enough to talk about having these moral truisms, as Dr. Nielsen does.