  Nine times in the Meditations, Marcus lays out the alternatives: providence, nature, reason, on the one hand, or atoms, on the other (iv.3, vi.24, vii.32, vii.50, viii.17, ix.28, xi.39, x.6, xi.18). (On these passages, see Cooper 2004.[5]) Although he does not explain, the reference is clear enough: either the world and what happens is the design of a providential God, as believed by the Stoics (and Platonists), or the outcome of atoms colliding randomly in the void, as believed by the Epicureans. What is not obvious is why Marcus is laying out these alternatives. Is it because his grasp of Stoic physics is so tenuous that he must be open to the possibility that Epicurean physics is true (Rist 1982, 43, Annas 2004, 116)? Marcus does at one point express despair about his own grasp of physics (vii.67). Or is his point that whether one’s physics is Epicurean or Stoic, one must live as the Stoics enjoin (Annas, 108–114, Hadot, 148), that is to say, rationally, with a single purpose, rising above conventional goods and evils (ix.28)?  Does the convergence of Epicureans and Stoics on such ethical points, in view of the two schools’ very different physical opinions, strengthen his confidence in the ethics (Annas, 109)?