- Wise men speak because they have something to say; Fools because they have to say something.
- Love is a serious mental disease.
- He who commits injustice is ever made more wretched than he who suffers it.
- Life must be lived as play.
- Know thyself.
- I know not how I may seem to others, but to myself I am but a small child wandering upon the vast shores of knowledge, every now and then finding a small bright pebble to content myself with.
- Thinking: The talking of the soul with itself.
- Those who intend on becoming great should love neither themselves nor their own things, but only what is just, whether it happens to be done by themselves or others.
- Knowledge becomes evil if the aim be not virtuous.
- For a man to conquer himself is the first and noblest of all victories.
- Courage is a kind of salvation.
- Human behavior flows from three main sources: desire, emotion, and knowledge.
- We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.
