Letters 110.11

What, then, do I now encourage you to do? Nothing new—we are not trying to find cures for new evils—but this first of all: namely, to see clearly for yourself what is necessary and what is superfluous. What is necessary will meet you everywhere; what is superfluous has always to be hunted out—and with great endeavour.

Seneca, Letters to Lucilius 110.11, translated by Richard Mott Gummere