The Swerve: How the World Became Modern

by Stephen Greenblatt

• Everything comes into being as a result of a swerve. If all the individual particles, in their infinite numbers, fell through the void in straight lines, pulled down by their own weight like raindrops, nothing would ever exist. But the particles do not move lockstep in a preordained single direction. Instead, “at absolutely unpredictable times and places they deflect slightly from their straight course, to a degree that could be described as no more than a shift of movement.” (2.218–20) The position of the elementary particles is thus indeterminate. The swerve—which Lucretius called variously declinatio, inclinatio, or clinamen—is only the most minimal of motions, nec plus quam minimum. (2.244) But it is enough to set off a ceaseless chain of collisions. Whatever exists in the universe exists because of these random collisions of minute particles. The endless combinations and recombinations, resulting from the collisions over a limitless span of time, bring it about that “the rivers replenish the insatiable sea with plentiful streams of water, that the earth, warmed by the sun’s fostering heat, renews her produce, that the family of animals springs up and thrives, and that the gliding ethereal fires have life.” (1.1031–34) • The swerve is the source of free will. In the lives of all sentient creatures, human and animal alike, the random swerve of elementary particles is responsible for the existence of free will. For if all of motion were one long predetermined chain, th...