The search for something permanent is one of the deepest of the instincts leading men to philosophy.

Human life, its growth, its hopes, fears, loves, et cetera, are the result of accidents

A life without adventure is likely to be unsatisfying, but a life in which adventure is allowed to take whatever form it will is sure to be short.

With the introduction of agriculture mankind entered upon a long period of meanness, misery, and madness, from which they are only now being freed by the beneficent operation of the machine.

Understanding human nature must be the basis of any real improvement in human life. Science has done wonders in mastering the laws of the physical world, but our own nature is much less understood, as yet, than the nature of stars and electrons. When science learns to understand human nature, it will be able to bring a happiness into our lives which machines and the physical sciences have failed to create.

The luxury to disparage freedom is the privilege of those who already possess it.

For my part I distrust all generalizations about women, favorable and unfavorable, masculine and feminine, ancient and modern; all alike, I should say, result from paucity of experience.