Finally, it is very necessary that the origin of morality (as indicated by Spencer in his Data of Ethics, by Darwin in his Descent of Man, by Prince Kropotkin in his Mutual Aid: A Factor of Evolution, and by Dr. C. W. Saleeby in his Evolution: The Master-Key) should be better understood. Hitherto the question of morality has been dealt with on wrong lines, [332] and this applies to the teaching not only of Christian but also of non-Christian religionists. It applies to the works of those speculative philosophers who have denied the empirical origin of man's moral feeling, and who have had recourse to subtle and unconvincing theories in order to assign a supernatural origin to the moral senses. These thinkers, in attempting to explain the "distinction of man," the "why of existence," and the "aim of nature," set themselves the hopeless task of explaining a process which entails untold suffering upon sentient beings, and in which the modern Rationalist is unable to discover any ethical principle whatsoever. Too much prominence cannot be given to the later conclusions of modern thought so eloquently set forth by Prince Kropotkin. Much as I appreciate all Mr. S. Laing's writings, and especially, perhaps, the chapter on "Practical Life" with which he closes his admirable work, Modern Science and Modern Thought, I cannot agree with him when he says (p. 113 of the R. P. A. Cheap Reprint): "For practical purposes it is comparatively unimportant how this [the moral] standard got there." It is, in my humble opinion, very important, for the reasons that are clearly demonstrated by Prince Kropotkin and other modern ethicists. So soon as the Darwinian theory of the origin of morals is fully accepted, great strides in the development of an improved morality will surely follow. In fine, "science, far from destroying the foundations of ethics, as it is so often accused of doing, gives to evolutionist ethics a philosophical certitude where the transcendental thinker had only a vague intuition to rely upon." [333] OPINIONS OF ETHICISTS. Let me now quote some instructive utterances by Rationalists [334]:--