This study is an original contribution to the discussion of Lucretius’ use of sources and his relationship to Epicurus; furthermore, it provides a new edition of fragments of books 14 and 15 of Epicurus’ On Nature. It focuses on understanding how Lucretius’ sources presented the Presocratics and assesses his literary achievement on that basis.This book will interest anyone studying the way in which Lucretius, and more generally Roman authors, adapted Greek literature and philosophy as well as those with an interest in Hellenistic philosophy and in the reconstruction of Epicurus’ treatise On Nature in particular.