In the book True Reason (Gilson and Weitnauer, eds.) Samuel Youngs asks “We are brutally aware of how often we come up short (what could be the evolutionary purpose for a sense of abiding discontentment with the world on moral grounds?). (p.176). The author is questioning what would enhance survival of our specie by us developing a psychological sense of moral guilt. If evolution is true, then all traits, even psychological ones, must enhance survival over those who do not have such thoughts. Note that the question is not one of why humans feel they need to be moral, but why all humans would have a sense of the existence of moral lack, somewhere in the world, as all of us seem to have at some point.
Indeed, the only explanation open to the atheist evolutionist is that moral failure is a type of false psychological trait that was somehow transferred from survival. For evolution to generate the psychological trait, we must not merely feel that moral lack inhibits reproduction, but the psychological trait must actually do so, or be a false transfer from something that actually does so. Evolution is shown to be seriously inadequate if it is shown to be an unreasonable source of such traits. In reality, our sense of moral failure surely has little to do with whether we live long enough to reproduce, leaving the human sense of moral failure as a false psychological trait.
The Bible has the account of Adam and Eve and their moral failure, an account Christians describe as the fall. This is the source of moral failure. Yet we are told by atheist evolutionists that the account of the fall is an invention of human literature. It would seem that if the evolutionists are correct, humans generated a false psychological trait, then invented the story of Adam to explain it. I wonder how far the chain of false creations can go.
Deep down, we all know that it is much more reasonable that moral lapses are quite real and there is a moral law that is external to the human condition that we compare ourselves to. Moral laws require a moral law giver, which we call God.
Of course, the dogmatic evolutionist will not be affected by this line of reasoning, since evolution is non-falsifiable. In an evolutionary viewpoint, any actually existing state of affairs is due to evolution. If people are altruistic and self-sacrificial, it is for survival of the tribe. If people are selfish and murderous, it is for survival of the individual. Evolutionists adapt the theory to fit the data, not the other way around.