The person who seeks all their applause from outside has their happiness in another’s keeping .

The line warns that basing self-worth on external approval makes one’s emotional life dependent on forces one cannot control: other people’s tastes, moods, and judgments. “Applause from outside” stands for social validation—praise, status, popularity—while “happiness in another’s keeping” suggests surrendering agency over one’s well-being. Read this way, the quote advocates an inward locus of evaluation: grounding confidence in personal standards, character, and purposeful action rather than in fluctuating public opinion. It aligns with a long moral-philosophical tradition (notably Stoic thought) that treats serenity as something secured by governing one’s own mind, not by chasing reputation.