Two places in this world make it impossible for a man to escape from himself: a battlefield and a prison cell.

If a man really knew himself he would utterly despise the ignorant notions others might form on a subject in which he had such matchless opportunities for observation.

A man may call to mind the face of his friend, but not his own. Here, then, is an initial difficulty in the way of applying the maxim, Know Thyself.

Go to your bosom; Knock there, and ask your heart what it doth know.

Self-knowledge is a dangerous thing, tending to make man shallow or insane.

Explore thyself. Herein are demanded the eye and the nerve.

All men should strive to learn before they die what they are running from, and to, and why.

Where is your Self to be found? Always in the deepest enchantment that you have experienced.

Men go abroad to wonder at the heights of mountains, at the huge waves of the sea, at the long courses of rivers, at the vast compass of the ocean, at the circular motion of the stars; and they pass by themselves without wondering.

He who knows others is learned; he who knows himself is wise.