§ 38. Here might be urged the necessity for preluding the study of moral science by the study of biological science. Here might be dwelt on the error men make in thinking they can understand those special phenomena of human life with which Ethics deals, while paying little or no attention to the general phenomena of human life, and while utterly ignoring the phenomena of life at large. And, doubtless, there would be truth in the inference that such acquaintance with the world of living things, as discloses the part which pleasures and pains have played in organic evolution, would help to rectify these one-sided conceptions of moralists. It cannot be held, however, that lack of this knowledge is the sole cause, or the main cause, of their one-sidedness. For facts of the kind above instanced, which, duly attended to, would prevent such distortions of moral theory, are facts which it needs no biological inquiries to learn, but which are daily thrust before the eyes of all. The truth is, rather, that the general consciousness is so possessed by sentiments and ideas at variance with the conclusions necessitated by familiar evidence that the evidence gets no attention. These adverse sentiments and ideas have several roots. There is the theological root. As before shown, from the worship of cannibal ancestors who delighted in witnessing tortures, there resulted the primitive conception of deities who were propitiated by the bearing of pains, and, consequently, angered by the receipt of pleasures. Through the religions of the semi-civilized, in which this conception of the divine nature remains conspicuous, it has persisted, in progressively modified forms, down to our own times; and still colors the beliefs, both of those who adhere to the current creed and of those who nominally reject it. There is another root in the primitive and still-surviving militancy. While social antagonisms continue to generate war, which consists in endeavors to inflict pain and death while submitting to the risks of pain and death, and which necessarily involves great privations, it is needful that physical suffering, whether considered in itself or in the evils it bequeaths, should be thought little of, and that among pleasures recognized as most worthy should be those which victory brings.