“Man know thyself; then thou shalt know the Universe and God.”
As quoted in Fragments of Reality: Daily Entries of Lived Life (2006) by Peter Cajander, p. 109
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Pythagoras 121
ancient Greek mathematician and philosopher -585–-495 BCRelated quotes

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 138.

Golden Sayings of Epictetus
Context: Even as bad actors cannot sing alone, but only in chorus: so some cannot walk alone. Man, if thou art aught, strive to walk alone and hold converse with yourself, instead of skulking in the chorus! at length think; look around thee; bestir thyself, that thou mayest know who thou art! (103).

The Tragic Sense of Life (1913), X : Religion, the Mythology of the Beyond and the Apocatastasis

Samuel Butler's Notebooks (1912) self censored "d_____d" in original publication
Context: It is the manner of gods and prophets to begin: "Thou shalt have none other God or Prophet but me." If I were to start as a God or a prophet I think I should take the line: "Thou shalt not believe in me. Thou shalt not have me for a God. Thou shalt worship any d_____d thing thou likest except me." This should be my first and great commandment, and my second should be like unto it.

Reported in Dictionary of Burning Words of Brilliant Writers (1895), p. 511.

“What thou thyself hatest, do to no man.”
Nicocles or the Cyprians, 3.61

X, 30
Meditations (c. 121–180 AD), Book X
Context: When thou art offended at any man's fault, forthwith turn to thyself and reflect in what manner thou doest error thyself... For by attending to this thou wilt quickly forget thy anger, if this consideration is also added, that the man is compelled; for what else could he do? or, if thou art able, take away from him the compulsion.