the sun moves and the earth is stationary, and science that the earth moves and the sun is comparatively at rest. How can we determine which of these opposite statements is the very truth till we know what motion is? If our idea of motion is but an accidental result of our present senses, neither proposition is true and both are true; neither true philosophically; both true for certain practical purposes in the system in which they are respectively found."
Again, if we are to allow the revision of the generalizations of science by the addition of acceptable but unverified doctrines, we must allow the right of similar revision by rejection. Mr. Wallace, for example, would be justified in adding to the certainties of organic evolution his idea of the special creation of the mind of man. The old notion of the separate existence of the Ego, which plays on the nerve cells of the brain as a musician on the keys of a piano, would still linger in psychology. The astral body would hover on the verge of physiology, and a strong plea would go up for the reality of Santa Claus.
I have a scientific friend who finds it necessary to exclude by force, from his biological beliefs, all that is unpleasant in the theories of evolution. And he has the same right to do this that Prof. Haeckel has to insist that any scientific beliefs, for which science has yet no warrant, are a necessary part of the orthodoxy of science.
For Haeckel is not content to speak for himself, asking tolerance by tolerance toward others. His belief is no idiosyncrasy of his own. He speaks for all. Every honest, intelligent, courageous scientific man, he tells us, so far as he is truthful, competent, and brave, shares the same belief. His confession of faith is nothing if not orthodox. He says:
"This monistic confession has the greater claim to an unprejudiced consideration in that it is shared, I am firmly convinced, by at least nine tenths of the men of science now living; indeed, I believe, by all men of science in whom the following four conditions are realized: (1) Sufficient acquaintance with the various departments of natural science, and in particular with the modern doctrine of evolution; (2) sufficient acuteness and clearness of judgment to draw by induction and deduction the necessary logical consequences that flow from such empirical knowledge; (3) sufficient moral courage to maintain the monistic knowledge, so gained, against the attacks of hostile dualistic and pluralistic systems; and (4) sufficient strength of mind to free himself by sound, independent reasoning from dominant religious prejudices, and especially from those irrational dogmas which have been firmly lodged in our minds from earliest youth as indisputable revelations."
