De rerum natura (Latin: [deː ˈreːrũː naːˈtuːraː]; On the Nature of Things) is a first-century BC didactic poem by the Roman poet and philosopher Lucretius (c. 99 BC – c. 55 BC) with the goal of explaining Epicurean philosophy to a Roman audience. The poem, written in some 7,400 dactylic hexameters, is divided into six untitled books, and explores Epicurean physics through richly poetic language and metaphors.