Democritus's atomism was refined and elaborated by the later Greek philosopher Epicurus (341–270 BC), and by the Roman Epicurean poet Lucretius (99–55 BC). During the Early Middle Ages, atomism was mostly forgotten in western Europe. During the 12th century, it became known again in western Europe through references to it in the newly-rediscovered writings of Aristotle.
Democritus's theory of atoms was further developed by Epicurus and Lucretius, who built upon his ideas. During the Early Middle Ages, atomism was largely forgotten in Western Europe but was later revived through references to it in the works of Aristotle.