To know, is to know that you know nothing.

The understanding of mathematics is necessary for a sound grasp of ethics.

True wisdom comes to each of us when we realize how little we understand about life, ourselves, and the world around us.

A free soul ought not to pursue any study slavishly, for nothing that is learned under compulsion stays with the mind.

It is not living that matters, but living rightly.

Is there anyone to whom you entrust a greater number of serious matters than your wife? And is there anyone with whom you have fewer conversations?

I call that man idle who might be better employed.