Letters 58.25

“Very well,” say you, “what good shall I get from all this fine reasoning?” None, if you wish me to answer your question. Nevertheless, just as an engraver rests his eyes when they have long been under a strain and are weary, and calls them from their work, and “feasts” them, as the saying is; so we at times should slacken our minds and refresh them with some sort of entertainment. But let even your entertainment be work; and even from these various forms of entertainment you will select, if you have been watchful, something that may prove wholesome.

Seneca, Letters to Lucilius 58.25, translated by Richard Mott Gummere