Chapter Fifty-Six of the Tao Te Ching
Those who know do not talk.
Those who talk do not know.
Guard your senses.
Temper your sharpness.
Simplify your problems.
Mask your brightness.
Be at one with the dust of the earth.
This is primal union. He who has achieved this state
Is unconcerned with friends and enemies,
With good and harm, with honor and disgrace.
This therefore is the highest state of man.