In recording his musings, Marcus sometimes speaks of God, sometimes of the gods. Is there inconsistency here? Not necessarily. For him, as we have seen, the world was governed by a cosmic consciousness which was a single immanent spirit. But that world was also a congeries of differing areas and elements and activities, and it was natural enough that the Greeks, whom the Romans followed in such matters, should think of these separate components as governed by specialized deities. Poseidon, the Roman's Neptune, was lord of the waters; Apollo was god of the sun and the realm of light; Demeter, or her Roman equivalent, Ceres, was goddess of the earth and harvests and fertility. Of these gods there was no fixed number, and as the empire expanded it took in, with a curious religious democracy, the gods of its new subjects. In this respect, Marcus was a singularly catholic theologian. Did he believe that all these motley figures, often beautifully embodied in Greek and Roman statuary, were real existences? Officially he did, for he was not only Emperor but Pontifex Maximus, the head of the Roman religion, who presided at celebrations of these deities and sacrifices to them. But one can only suspect that he did so with tongue in cheek. To a mind as sophisticated as his, these lesser deities were probably symbols of the one divine activity, which manifested itself throughout all these domains. If he insisted, as he did, on retaining old forms of Roman worship, it was probably because he saw that myth, besides being a powerful preservative of people's unity, may carry a truth in metaphorical form that the more correct philosophic formulae may fail to convey.
-Brand Blanshard, as excerpted from his essay on Marcus Aurelius in Four Reasonable Men: Marcus Aurelius, John Stuart Mill, Ernest Renan, Henry Sidgwick