The guiding motto in the life of every natural philosopher should be, seek simplicity and distrust it.

Mathematics, in its widest significance, is the development of all types of formal, necessary, deductive reasoning.

The motive of success is not enough.

But harmony is limitation. Thus rightness of limitation is essential for growth of reality. Unlimited possibility and abstract creativity can procure nothing.

It is a safe rule to apply that, when a mathematical or philosophical author writes with a misty profundity, he is talking nonsense.

That knowledge which adds greatness to character is knowledge so handled as to transform every phase of immediate experience.

People make the mistake of talking about 'natural laws.' There are no natural laws. There are only temporary habits of nature.