The logic implies that it may be only natural for robot vehicles [us] to murder, rob, rape or enslave other robots to satisfy their genetic masters. Indeed, ruthless extermination of rival genes should be nearly as powerful an imperative as propagation of one’s own. Modern Darwinism seems also to leave no basis for valuing the humane arts like poetry and music except to the extent that such things are useful in spreading the genes by (for example) building tribal solidarity. Nineteenth-century Darwinists, writing for European gentlemen who took their own social order for granted, might have been able to shrug aside such objections on the ground that science requires that we take an unsentimental view of the realities of life. Darwin himself coolly predicted in The Descent of Man that the most highly developed humans would soon exterminate the other races because that is how natural selection works. Such casual references to genocide only began to seem reprehensible after Hitler, Stalin and Mao demonstrated what they meant in practice. Nowadays even the most uncompromising Darwinists have to make some concessions to morality, even at the cost of logical contradiction.