The Epicureans believed that the way to personal happiness was to be found not in religion, which they despised, but in relying for knowledge about the world only on what their senses could tell them. There is no more passionate atheist than Lucretius - his condemnation of religion and espousal of Epicurean atomism has an evangelical intensity.
In the dark, confused days presaging the end of the republic, voices were abroad which questioned prevailing views about the natural and spiritual worlds. Some of these belonged to the Epicureans, a school of Greek philosophy founded by Epicurus (341 - 270 BC) whose tenets included a rudimentary theory of the atomic nature of matter. Epicurus believed, too, that every happening had a natural cause and that the ultimate aim in life was the pleasure that could be derived from the harmony of body and mind.
Among the staunchest followers of Epicureanism in Italy was Titus Lucretius Carus (c. 99 - 55 BC). His De Rerum Natura (On the Nature of Things) comprises the first six books, some 7500 hexameters, of an unfinished philosophical poem unique in Latin. It is a work of great learning and great poetry; also of considerable insight, in that while subscribing to the Epicurean objection to spiritual gods and their images, he anticipated the kind of dilemma the modern biologist has with regard, for instance, to Christianity.
The famous second- or first-century BC statue known as the Venus de Milo. (VRoma: Louvre, Paris: Barbara McManus)
So Lucretius invests Venus, whom he invokes at the beginning of the poem, with an overall creative power in nature, before entering into his exposition of the composition of matter and space in atomic terms. He goes on to discuss the mind, life itself, feeling, sex, thought, cosmology, anthropology, meteorology, and geology. De Rerum Natura is thus not so much a philosophical work as a scientific treatise; it is a mark of the skill of Lucretius that he succeeded in presenting it in the language and metre of poetry.
All we are told about the life of Lucretius is that he was poisoned by a love potion administered by his wife, went mad, wrote poetry in lucid spells, and committed suicide at the age of 44.