Testimonia et Fragmenta
Cleanthes
Cleanthes. Stoicorum veterum fragmenta, Vol. 1. von Arnim, Hans Friedrich August, editor. Stuttgart: Teubner, 1903. (1964 printing.)
Sextus adv. math. XI 74. ἀλλὰ Κλεάνθης μὲν μήτε κατὰ φύσιν αὐτὴν (scil. τὴν ἡδονὴν) εἶναι μήτ’ ἀξίαν ἔχειν αὐτὴν ἐν τῷ βίῳ, καθάπερ δὲ τὸ κάλλυντρον κατὰ φύσιν μὴ εἶναι.