Of all the inventions of man I doubt whether any was more easily accomplished than that of a Heaven.

Nothing reveals a man's character better than the kind of joke at which he takes offense.

Many are less fortunate than you' may not be a roof to live under, but it will serve to retire beneath in the event of a shower.

All mathematical laws which we find in Nature are always suspect to me, in spite of their beauty. They give me no pleasure. They are merely auxiliaries. At close range it is all not true.

The worst thing you can possibly do is worrying and thinking about what you could have done.

The ordinary man is ruined by the flesh lusting against the spirit; the scholar by the spirit lusting too much against the flesh.

One has to do something new in order to see something new.