I never held Negroes to be inherently inferior. The statement in Marriage and Morals refers to environmental conditioning. I have had it withdrawn from subsequent editions because it is clearly ambiguous.

The human animal, like others, is adapted to a certain amount of struggle for life [and] the mere absence of effort from his life removes an essential ingredient of happiness. [. . .] He forgets that to be without some of the things you want is an indispensable part of happiness.

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.

The satisfaction to be derived from success in a great constructive enterprise is one of the most massive that life has to offer.

In attempting to understand the elements out of which mental phenomena are compounded, it is of the greatest importance to remember that from the protozoa to man there is nowhere a very wide gap either in structure or in behaviour. From this fact it is a highly probable inference that there is also nowhere a very wide mental gap.

Science, by itself, cannot supply us with an ethic. It can show us how to achieve a given end, and it may show us that some ends cannot be achieved.

If everything has a cause, then God must have a cause. If there can be anything without a cause, it may just be the world as God.