is the constant practise of critical thinking. We ought never to accept fantastic notions of any kind; we ought to test all notions; we ought to pursue all propositions until we find out their connection with reality. That is the fashion of thinking which we call scientific in the deepest and broadest sense of the word. It is, of course, applicable over the whole field of human interests, and the habit of mind which insists on finding realities is the best product of an education which may be properly called scientific. I have no doubt that, in your lifetime, you will see questions arise out of popular notions and faiths, which will call for critical thinking such as has never been required before, especially as to social relations, political institutions, and economic interests.
Here I may notice, in passing, the difference between science and religion in regard to the habits of thought which each encourages. No religion ever offers itself except as a complete and final answer to the problems of life. No religion ever offers itself as a tentative solution. A religion cannot say: I am the best solution yet found, but I may be superseded tomorrow by new discoveries. But that is exactly what every science must say. Religions do not pretend to grow; they are born complete and fully correct and our duty in regard to them is to learn them in their integrity. Hence Galton says that "the religious instructor, in every creed, is one who makes it his profession to saturate his pupils with prejudice."[1]
Every science contains the purpose and destiny of growth as one of its distinguishing characteristics; it must always be open to re-examination and must submit to new tests if such are proposed. Consequently the modes and habits of thought developed by the study of
- ↑ Hereditary Genius, p. 210.
