He who knows others is wise, he who himself is enlightened. – Lao Tzu
Know thy self is the beginning of wisdom. – Socrates
There are three things extremely hard, steel, a diamond, and to know one’s self. – Benjamin Franklin
The unexamined life is not worth living. – Socrates
Know the enemy and know yourself. – Sun Tzu
The first thing you have to know is yourself. A man who knows himself can step outside himself and watch his own reaction like an observer. – Adam Smith