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He who follows reason in all things is both tranquil and active at the same time, and also cheerful and collected.

Epictetus, Marcus Aurelius, Lucius Annaeus Seneca (2016). “Stoic Six Pack: Meditations of Marcus Aurelius, Golden Sayings, Fragments and Discourses of Epictetus, Letters from a Stoic and The Enchiridion”, p.111, Enhanced Media Publishing
He who follows reason in all things is both tranquil and active at the same time, and also cheerful and collected.