On all such subjects there is no science, but only a sort of ardent ignorance; and nobody has ever been able to offer any theories of moral heredity which justified themselves in the only scientific sense; that is, that one could calculate on them beforehand. There are six cases, say, of a grandson having the same twitch of mouth or vice of character as his grandfather; or perhaps there are sixteen cases, or perhaps sixty. But there are not two cases, there is not one case, there are no cases at all, of anybody betting half a crown that the grandfather will have a grandson with the twitch or the vice. In short, we deal with heredity as we deal with omens, affinities and the fulfillment of dreams. The things do happen, and when they happen we record them; but not even a lunatic ever reckons on them. Indeed, heredity, like the dreams and omens, is a barbaric notion; that is, not necessarily an untrue, but a dim, groping and unsystematised notion. A civilised man feels himself a little more free from his family. Before Christianity these tales of tribal doom occupied the savage North; and since the Reformation and the revolt against Christianity (which is the religion of a civilised freedom) savagery is slowly creeping back in the form of realistic novels and problem plays.