Every ist writes his own autobiography.

Reproduction is so primitive and fundamental a function of vital organisms that the mechanism by which it is assured is highly complex and not yet clearly understood. It is not necessarily connected with sex, nor is sex necessarily connected with reproduction.

The omnipresent process of sex, as it is woven into the whole texture of our man's or woman's body, is the pattern of all the process of our life.

All the art of living lies in a fine mingling of letting go and holding on.

Men who know themselves are no longer fools. They stand on the threshold of the door of Wisdom.

The world's greatest thinkers have often been amateurs; for high thinking is the outcome of fine and independent living, and for that a professional chair offers no special opportunities.

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.