The greatest task before civilization at present is to make machines what they ought to be, the slaves, instead of the masters of men.

I regard sex as the central problem of life. And now that the problem of religion has practically been settled, and that the problem of labor has at least been placed on a practical foundation, the question of sex—with the racial questions that rest on it—stands before the coming generations as the chief problem for solution. Sex lies at the root of life, and we can never learn to reverence life until we know how to understand sex.

What we call 'morals' is simply blind obedience to words of command.

The immense value of becoming acquainted with a foreign language is that we are thereby led into a new world of tradition and thought and feeling.

Had there been a Lunatic Asylum in the suburbs of Jerusalem, Jesus Christ would infallibly have been shut up in it at the outset of his public career. That interview with Satan on a pinnacle of the Temple would alone have damned him, and everything that happened after could have confirmed the diagnosis. The whole religious complexion of the modern world is due to the absence from Jerusalem of a Lunatic Asylum.

One can know nothing of giving aught that is worthy to give unless one also knows how to take.

The by-product is sometimes more valuable than the product.