The fly that doesn't want to be swatted is most secure when it lights on the fly-swatter.

A book which, above all others in the world, should be forbidden, is a catalogue of forbidden books.

It is a sure evidence of a good book if it pleases us more and more as we grow older.

It is a question whether, when we break a murderer on the wheel, we do not fall into the error a child makes when it hits the chair it has bumped into.

We are obliged to regard many of our original minds as crazy at least until we have become as clever as they are.

They do not think, therefore they are not.

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.