"The only true wisdom is in knowing you know nothing."

"The fool doth think he is wise, but the wise man knows himself to be a fool."

"Knowing yourself is the beginning of all wisdom."

"He who has a why to live can bear almost any how."

"The measure of intelligence is the ability to change."

"Silence is a source of great strength."

"A wise man can learn more from a foolish question than a fool can learn from a w..."

"Science is organized knowledge. Wisdom is organized life."