The characteristic of a philosopher is that he looks to himself for all help or harm. The marks of a proficient are that he censures no one, praises no one, blames no one, accuses no one, says nothing concerning himself as being anybody, or knowing anything. When he is in any instance hindered or restrained he accepts this as his own responsibility. If he is praised, he smiles to himself at the person who praises him. If he is censured, he makes no defense. But he goes about with the caution of a convalescent, wary of anything that may suggest he is well. He restrains desire; he transfers his aversion to those things only which thwart the proper use of his own will; he employs his energies moderately in all directions; if he appears stupid or ignorant, he does not care; in a word, he keeps watch over himself as over an enemy and one in ambush.

Epictetus (55 – 135 A.D.)