Definition
Friendship, in Stoic ethics, is a relationship grounded in mutual goodwill and shared commitment to living virtuously. The Stoics held that human beings are naturally social, made for cooperation, and that genuine friendship is one of the fullest expressions of that nature.
A true friend is valued not for advantage gained but for their character. Such friendship is reciprocal, honest, and stable, because it rests on virtue rather than on shifting interest or pleasure.
Why it matters
How it works
The Stoic approach to friendship balances warmth with realism. One forms close bonds and gives loyalty fully, yet remembers that a friend, like all externals, can be lost. The premeditation of loss is meant to deepen gratitude, not to harden the heart.
Friendship also serves moral progress. Seneca advised choosing companions who improve you and whom you can improve, since character is partly shaped by the company kept.