A passage from Marcus Aurelius
Marcus Aurelius, Meditations 9.4
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He who does wrong does wrong against himself. He who acts unjustly acts unjustly to himself, because he makes himself bad.
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At dawn, when you have trouble getting out of bed, tell yourself: 'I have to go to work — as a human being.'
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Take care not to be Caesarified, or dyed with purple; for it does happen. Keep thyself then simple, good, pure, serious, free from affectation.
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It is a man's special privilege to love even those who wrong him.