The Swerve: How the World Became Modern

by Stephen Greenblatt

In constant motion, atoms collide with each other, Epicurus reasoned, and in certain circumstances, they form larger and larger bodies. The largest observable bodies—the sun and the moon—are made of atoms, just as are human beings and waterflies and grains of sand. There are no supercategories of matter; no hierarchy of elements. Heavenly bodies are not divine beings who shape our destiny for good or ill, nor do they move through the void under the guidance of gods: they are simply part of the natural order, enormous structures of atoms subject to the same principles of creation and destruction that govern everything that exists. And if the natural order is unimaginably vast and complex, it is nonetheless possible to understand something of its basic constitutive elements and its universal laws. Indeed, such understanding is one of human life’s deepest pleasures. This pleasure is perhaps the key to comprehending the powerful impact of Epicurus’ philosophy; it was as if he unlocked for his followers an inexhaustible source of gratification hidden within Democritus’ atoms. For us, the impact is rather difficult to grasp. For one thing, the pleasure seems too intellectual to reach more than a tiny number of specialists; for another, we have come to associate atoms far more with fear than with gratification. But though ancient philosophy was hardly a mass movement, Epicurus was offering something more than caviar to a handful of particle physicists. Indeed, eschewing the self-...