A quote
The two kinds of goods which are of a higher order are different; the primary are according to nature,—such as deriving joy from the dutiful behaviour of one’s children and from the well-being of one’s country. The secondary are contrary to nature,—such as fortitude in resisting torture or in enduring thirst when illness makes the vitals feverish.
Seneca·Letter 66 — On Various Aspects of Virtue (§37)·trans. Gummere