 Both philosophy and politics are spheres in which we can benefit others (On Peace of Mind 3.1–3). The contrast between the life of theory and the life of politics helps Seneca spell out his version of Stoic cosmopolitanism. We should not think of the choice between philosophy and politics as a choice between theory and practice. Rather, philosophy and politics represent two worlds that we simultaneously belong to. The world of politics is our local world; the world of philosophy is the whole world. By pursuing an active career in politics, we aim to do good to the people in our vicinity. By retreating into philosophy we choose to live, for a while, predominantly in the world at large (Wildberger 2018a). By studying, teaching, and writing philosophy, Seneca thinks, we help others who are not necessarily spatially close to us. Philosophical study is beneficial (or ‘of benefit’), it is of use to others, in the world-wide community to which we all belong (On the Private Life 3.4–4.2).