Letters 9.5

In this sense the wise man is self-sufficient, that he can do without friends, not that he desires to do without them. When I say “can,” I mean this: he endures the loss of a friend with equanimity.

But he need never lack friends, for it lies in his own control how soon he shall make good a loss. Just as Phidias, if he lose a statue, can straightway carve another, even so our master in the art of making friendships can fill the place of a friend he has lost.

Seneca, Letters to Lucilius 9.5, translated by Richard Mott Gummere