Wisdom begins in wonder.

I know what I do not know.

I know that I am intelligent, because I know that I know nothing.

Regard your good name as the richest jewel you can possibly be possessed of - for credit is like fire; when once you have kindled it you may easily preserve it, but if you once extinguish it, you will find it an arduous task to rekindle it again. The way to gain a good reputation is to endeavor to be what you desire to appear.

In every one of us there are two ruling and directing principles, whose guidance we follow wherever they may lead; the one being an innate desire of pleasure; the other, an acquired judgment which aspires after excellence.

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?

To be uncertain is to be uncomfortable, but to be certain is to be ridiculous.