Happiness is man's greatest aim in life. Tranquility and rationality are the cornerstones of happiness.

Let no one be slow to seek wisdom when he is young nor weary in the search of it when he has grown old. For no age is too early or too late for the health of the soul.

Is he able, but not willing? Then he is malevolent.

I have never wished to cater to the crowd; for what I know they do not approve, and what they approve I do not know.

Let no one delay the study of philosophy while young nor weary of it when old.

As if they were our own handiwork we place a high value on our characters.

Don't fear god, Don't worry about death; What is good is easy to get, and What is terrible is easy to endure