Significant discussion recently here on the forum about emergence and Epicurus' opposition to Democritus' atomic reductionism, so just bumping this thread to remind people of the existence of this article by David Sedley directly on point.
The topic with which this paper’ will concern itself is the relation in which, according to Epicurean metaphysics, a complex entity such as a man stands to its constituent parts and qualities. Although Epicureanism and Stoicism both give centre stage to bodily particulars, and in consequence have certain features of their respective epistemologies in common, their metaphysical systems are nevertheless in fact extraordinarily different. Stoicism is a top-down theory, which takes life and intelligence as irreducibly basic features of the world and of at least some of its occupants. The reason why all but a very few of the items in the world, including mental qualities such as virtue, are bodies, is not that body is more metaphysically fundamental than mind or intelligence, but simply that the ability of such things to cause anything is held to depend on their capacity for bodily interaction. In Epicureanism, on the other hand, bodies are indeed metaphysically fundamental, since they are, apart from the space which they occupy and move through, the only conceivable per se entities. Yet a Stoic-like concern with causality is hardly in evidence here, since in Epicureanism causal interaction goes on all the time between bodies and certain non-corporeal items, namely their properties.
