For our improvement we need a mirror.

Unrest is the mark of existence.

As the biggest library if it is in disorder is not as useful as a small but well-arranged one, so you may accumulate a vast amount of knowledge but it will be of far less value than a much smaller amount if you have not thought it over for yourself.

The mother of useful arts is necessity; that of the fine arts is luxury. For father the former has intellect; the latter genius, which itself is a kind of luxury.

There is only one healing force, and that is nature; in pills and ointments there is none. At most they can give the healing force of nature a hint about where there is something for it to do.

If two men who were friends in their youth meet again when they are old, after being separated for a life-time, the chief feeling they will have at the sight of each other will be one of complete disappointment at life as a whole; because their thoughts will be carried back to that earlier time when life seemed so fair as it lay spread out before them in the rosy light of dawn, promised so much — and then performed so little.

Faith is like love: it does not let itself be forced.