The teachings of Epicurus-about life and death, religion and science, physical sensation, happiness, morality, and friendship-attracted legions of adherents throughout the ancient Mediterranean world and deeply influenced later European thought. Though Epicurus faced hostile opposition for centuries after his death, he counts among his many admirers Thomas Hobbes, Thomas Jefferson, Karl Marx, and Isaac Newton. This volume includes all of his extant writings-his letters, doctrines, and Vatican sayings-alongside parallel passages from the greatest exponent of his philosophy, Lucretius, extracts from Diogenes Laertius Life of Epicurus, a lucid introductory essay about Epicurean philosophy, and a foreword by Daniel Klein, author of Travels with Epicurus and coauthor of the New York Times bestseller Plato and a Platypus Walk into a Bar.