Duty comes from inside, obligation from outside. When we act out of a sense of duty, we do so voluntarily to lift ourselves, and others, higher. When we act out of obligation, we do so to shield ourselves, and only ourselves, from repercussions. Marcus was aware of this distinction, but, as usual, needed to remind himself of it. “At dawn, when you have trouble getting out of bed, tell yourself: ‘I have to go to work—as a human being.’ ” Not as a Stoic or an emperor, or even as a Roman, but as a human being.
