I shall keep it [the manuscript] by me until the end of May for purposes of revision, and of adding malicious foot-notes. - Bertrand Russell

Self-respect will keep a man from being abject when he is in the power of enemies, and will enable him to feel that he may be in the right when the world is against him.

Ordinary language is totally unsuited for expressing what physics really asserts, since the words of everyday life are not sufficiently abstract. Only mathematics and mathematical logic can say as little as the physicist means to say.

Change is one thing, progress is another.