The greatest events occur without intention playing any part in them; chance makes good mistakes and undoes the most carefully planned undertaking. The world's greatest events are not produced, they happen.

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

A good method of discovery is to imagine certain members of a system removed and then see how what is left would behave: for example, where would we be if iron were absent from the world: this is an old example.

With prophecies the commentator is often a more important man than the prophet.

One's first step in wisdom is to question everything - and one's last is to come to terms with everything.

God creates the animals, man creates himself.

One cannot demand of a scholar that he show himself a scholar everywhere in society, but the whole tenor of his behavior must none the less betray the thinker, he must always be instructive, his way of judging a thing must even in the smallest matters be such that people can see what it will amount to when, quietly and self-collected, he puts this power to scholarly use.