Two and half centuries ago, John Adams complained, “Our modern philosophers are all the low grovelling disciples of Epicurus.” That’s even truer today. The ancient Greek philosopher Epicurus is—acknowledged or not—the source of secular “woke” liberalism. In his own time, Epicurus was a fringe thinker. He and his few followers speculated about how invisibly small entities of indivisible matter called “atoms,” hurtling endlessly through an infinite void according to fixed physical laws, could explain the world and everything in it. Most ancient philosophers thought his speculations abstruse and counterintuitive, and he gained few adherents. But today, the overwhelming success of modern science has turned Epicurus’ fringe philosophy into the governing worldview of nearly everyone. Atoms hurtling through a void—that is what everything is made of, according to our scientific gurus. Along with this new atomism has come a whole constellation of fashionable Epicurean ideas: that peace and contentment are the most important things in life, that reality is an infinite expanse of multiverses, that divine power has no part to play in human affairs. Epicureanism is the philosophy that now runs the world—and if we are to understand ourselves in the twenty-first century, we must understand Epicurus, who died in the third century B.C. In this convenient volume, the classicist Spencer A. Klavan presents core selections from Epicurus’ own writings and those of his most famous ancient disciple, the poet Lucretius. Listen in as the teacher outlines for his students how his system of physics, logic, and ethics works. Read the elegant presentations of these Epicurean ideas aimed at the Roman upper crust. And consider with Klavan how this philosophy has gripped the modern mind, why it is falling apart, and why it leaves confusion in its wake.