Change is one thing, progress is another.

I do not pretend to be able to prove that there is no God. I equally cannot prove that Satan is a fiction. The Christian god may exist; so may the gods of Olympus, or of ancient Egypt, or of Babylon. But no one of these hypotheses is more probable than any other: they lie outside the region of even probable knowledge, and therefore there is no reason to consider any of them.

The doctrine (of) maintaining that the language of daily life, with words used in their ordinary meanings, suffices for philosophy . . . I find myself totally unable to accept . . . . Because it makes almost inevitable the perpetuation amongst philosophers of the muddle-headedness they have taken over from common sense.

Protagoras did not know if the gods exist, but he held in any case they ought to be worshiped. Philosophy, according to him, had nothing edifying to teach, and for the survival of morals we must rely upon the thoughtlessness of the majority and their willingness to believe what they had been taught.

We do not like to be robbed of an enemy; we want someone to hate when we suffer. It is so depressing to think that we suffer because we are fools; yet, taking mankind in the mass, that is the truth.

In the first place a philosophical proposition must be general. It must not deal specially with things on the surface of the earth, or within the solar system, or with any other portion of space and time. . . . This brings us to a second characteristic of philosophical propositions, namely that they must be a priori. A philosophical proposition must be such as can neither be proved nor disproved by empirical evidence. . . . Philosophy, if what has been said is correct, becomes indistinguishable from logic as that word has now come to be used.

I believe myself that romantic love is the source of the most intense delights that life has to offer. In the relation of a man and woman who love each other with passion and imagination and tenderness, there is something of inestimable value, to be ignorant of which is a great misfortune to any human being.