Lucretius is so well known to be an Epicurean poet that it may seem pointless to investigate his philosophical influences. The situation should be straightforward, but many un-Epicurean influences have been noticed in De rerum natura, and there has been considerable argument over whether, or to what degree, these are philosophical or simply poetic influences. The fact that Lucretius uses the medium of verse for his philosophical exposition complicates the picture. He has a marked tendency to appropriate the language and imagery of his “opponents” and use them to argue against their world view. So we can say, for example, that he is an Ennian poet, because of his use of Ennius as a poetic source, while he disagrees fundamentally wit...