My friend...care for your psyche...know thyself, for once we know ourselves, we may learn how to care for ourselves.

The man who is truly wise knows that he knows very little.

I am a fool, but I know I'm a fool and that makes me smarter than you.

The more I learn, the less I realize I know.

Wisdom is knowing what you don't know.

Knowing thyself is the height of wisdom.