If you are pained by anything without, it is not the thing agitates you, but your own judgment concerning the thing; and this it is in your own power to efface.[Εἰ μὲν διά τι τῶν ἐκτὸς λυπῇ, οὐκ ἐκεῖνό σοι ἐνοχλεῖ, ἀλλὰ τὸσὸν περὶ αὐτοῦ κρῖμα, τοῦτο δὲ ἤδη ἐξαλεῖψαι ἐπὶ σοί ἐστιν.]

Source:Marcus Aurelius Antoninus to Himself (ed. Macmillan, 1898), (tr. Rendall), Book 8, #47, Page 119
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