Some theories are good for nothing except to be argued about.

There are people who possess not so much genius as a certain talent for perceiving the desires of the century, or even of the decade, before it has done so itself.

Above all things expand the frontiers of science: without this the rest counts for nothing.

In each of us there is a little of all of us.

Everyone is perfectly willing to learn from unpleasant experience - if only the damage of the first lesson could be repaired.

Once we know our weaknesses they cease to do us any harm.

The Greeks possessed a knowledge of human nature we seem hardly able to attain to without passing through the strengthening hibernation of a new barbarism.