Truth is for the gods; from our human point of view, it is an ideal, towards which we can approximate, but which we cannot hope to reach.

It has been said that man is a rational animal. All my life I have been searching for evidence which could support this.

As I grew up I became increasingly interested in philosophy, or which [his family] profoundly disapproved. Everytime the subject came up they repeated with unfailing regularity, "What is mind? No matter. What is matter? Never mind." After some fifty or sixty repititions, this remark ceased to amuse me.

The essence of the liberal outlook lies not in what opinions are held, but in how they are held; instead of being held dogmatically, they are held tentatively, and with a consciousness that new evidence may at any moment lead to their abandonment.

The practice of inhibiting impulses, which is to a great extent necessary to civilized life, makes mistakes easier, by preventing experience of the actions to which a desire would otherwise lead, and by often causing the inhibited impulses themselves to be unnoticed or quickly forgotten.

Contempt for happiness is usually contempt for other people's happiness, and is an elegant disguise for hatred of the human race.

Be isolated, be ignored, be attacked, be in doubt, be frightened, but do not be silenced.