When discussing the origins of morality, most Atheists are willing to offer evolution as a viable option. However, I believe it is obvious that the evolutionary process could not have produced moral imparitives.
A cursory reflection on our own interactions with others should make this obvious. We punish those who would exploit the weak. We look down on those who put their own self interest before others. We rebuke our children for not sharing their personal belongings (a trait found in every child).
How does the person who would accept that morality can be explained through the evolutionary process explain the fact that we actively condition ourselves to fight our base instincts which we possess because the naturalistic process has placed it in us? Why do we not trust evolution’s outworkings in ourselves as it relates to morality that we have to fight it?