Mundus fit munditer. Marcus Aurelius 4.27

The world is a well-appointed order, for it contains you: inside yourself, in the inner workings of your body and soul, you see a little vision of the grand harmony that inhabits the entire universe. Here Marcus Aurelius sums up a vision of man as microcosm that appears elsewhere in great poetry (Homer, Sappho) or philosophy (Plato, but also Democritus).

Ἤτοι κόσμος διατεταγμένος ἢ κυκεὼν συμπεφορημένος μέν, ἀλλὰ κόσμος· ἢ ἐν σοὶ μέν τις κόσμος ὑφίστασθαι δύναται, ἐν δὲ τῷ παντὶ ἀκοσμία; καὶ ταῦτα οὕτως πάντων διακεκριμένων καὶ διακεχυμένων καὶ συμπαθῶν.

The world is either a well-appointed ornament, or a scattered heap that nonetheless retains some order. For can you suppose that any order would exist in yourself, if the whole you inhabit were utterly chaotic? Within ourselves, as without, we see all things separating and combining, drawn together and apart by mutual sympathy.