The belief in God, the author says, is not innate or intuitive in man, but only arises after long culture. As to the bearing of the evolution theory on the immortality of the soul, Darwin thinks few people will find cause for anxiety in the impossibility of determining at what period in the ascending scale man became an immortal being. "The birth, both of the species and of the individual, are equally parts of that grand sequence of events, which our minds refuse to accept as the result of blind chance. The understanding revolts at such a conclusion." The bearing of the Darwinian doctrine on some important practical questions for society leads to the remark that, while man scans with scrupulous care the pedigree of his animals, when he comes to his own marriage he rarely or never takes any such care. Perhaps Darwin was somewhat in error here; and, also, he seems to have underrated the unconscious tendency to act according to natural law, which has no doubt influenced mankind largely. He lays down the principle that both sexes ought to refrain from marriage if markedly inferior in body or mind, or if they cannot avoid abject poverty for their children. When the laws of inheritance are thoroughly known, he says, we shall not hear ignorant members of our legislature rejecting with scorn a plan for ascertaining, by an easy method, whether or not consanguineous marriages are injurious to man. But Darwin is by no means in favour of any restriction on man's natural rate of increase; for it is the greatest means of preventing indolence from causing the race to become stagnant or to degenerate. Only, there should be open competition for all men; and the most able should not be prevented by laws or customs from succeeding best and rearing the largest number of offspring.