Naturlehre
From LSJ
τὸ δ' ἡδέως ζῆν καὶ ἱλαρῶς οὐκ ἔξωθέν ἐστιν, ἀλλὰ τοὐναντίον ὁ ἄνθρωπος τοῖς περὶ αὑτὸν πράγμασιν ἡδονὴν καὶ χάριν ὥσπερ ἐκ πηγῆς τοῦ ἤθους προστίθησιν → but a pleasant and happy life comes not from external things, but, on the contrary, man draws on his own character as a source from which to add the element of pleasure and joy to the things which surround him
