Empedocles was a native of Acragas (Agrigento) in Sicily, and attained a remarkable personal and religious importance, being a poet, orator, scientist, statesman, miracle worker, and in his own eyes a god. The legend that he died by throwing himself into Mount Etna witnesses the semidivine status that he managed to achieve. In his principal philosophical poem, On Nature, he replaces the Parmenidean One (see Parmenides of Elea) with a universe whose changes were the recombination of four basic and permanent elements, air, earth, fire, and water, mixing and separating under the influence of two forces, attraction (Love) and repulsion (Strife). The universe moves through cycles according to whichever one of these is predominant. He also proclaims the Pythagorean doctrine of the pre-existence and immortality of the soul and the contingency of its bodily existence: souls are condemned to the cycle of birth and rebirth by a fall from heavenly grace. His other main poem, Purifications, associates his cosmology and doctrine of the soul with a theological system in which Love, or a principle of organization, is present throughout the universe. Empedocles also held a doctrine of the evolution of the species. The exact way in which he reconciled the natural and the theological elements of his philosophy is controversial, but the doctrine of the four elements was taken over by Aristotle and thence by the medievals.