κακῶς εἰκάζειν περί

From LSJ

οὐκ ἔστι λύπης, ἄν περ ὀρθῶς τις σκοπῇ, ἄλγημα μεῖζον τῶν ἐν ἀνθρώπου φύσει → amongst the natural ills of man there is, if one but look at it aright, no greater pain than grief

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