The more unintelligent a man is, the less mysterious existence seems to him.

A man can be himself only so long as he is alone.

Memory works like the collection glass in the Camera obscura: it gathers everything together and therewith produces a far more beautiful picture than was present originally.

Just as one spoils the stomach by overfeeding and thereby impairs the whole body, so can one overload and choke the mind by giving it too much nourishment. For the more one reads the fewer are the traces left of what one has read; the mind is like a tablet that has been written over and over. Hence it is impossible to reflect; and it is only by reflection that one can assimilate what one has read. If one reads straight ahead without pondering over it later, what has been read does not take root, but is for the most part lost.

It is difficult to find happiness within oneself, but it is impossible to find it anywhere else.

Many books serve merely to show how many ways there are of being wrong, and how far astray you yourself would go if you followed their guidance. You should read only when your own thoughts dry up.

Man may have the most excellent judgment in all other matters, and yet go wrong in those which concern himself; because here the will comes in and deranges the intellect at once. Therefore let a man take counsel of a friend. A doctor can cure everyone but himself; if he falls ill, he sends for a colleague.