If you wish to upset the law that all crows are black, you mustn't seek to show that no crows are; it is enough if you prove one single crow to be white.

A good hypothesis in science must have other properties than those of the phenomenon it is immediately invoked to explain, otherwise it is not prolific enough.

An idea, to be suggestive, must come to the individual with the force of revelation.

We forget that every good that is worth possessing must be paid for in strokes of daily effort.

We may be in the Universe as dogs and cats are in our libraries, seeing the books and hearing the conversation, but having no inkling of the meaning of it all.

To spend life for something which outlasts it.

Our view of the world is truly shaped by what we decide to hear.