Intorno alla meccanica nel De rerum natura: la psicologia come machina in Lucrezio

The aim of this essay is to discuss the influence of mechanics on De rerum natura, specially in book iv, vv. 823-906. By referring to a quotation from ps.-Aristotle, mechanics is the minus which moves the plus, as a little lever (rhope) can move a heavy body. In this way, anima can be called mechane, since anima is less heavy than the bodies it moves and because it is made of atoms (elementa) which are qualitatively (not quantitatively) lighter than atoms of other bodies. Using me- chanical concepts, Lucretius structures a mechanical psychology, where atoms are considered in their ousiologic value (in fact, in ancient Greek atomos is a feminine noun, understanding ousia). Finally, in Lucretius mechanics is consid- ered politically : here the minus is the leader while the plus is the city he rules over.