Epicurus · Philosophy
Epicurus’ physics: he took Democritus’ atoms and void but added a single, momentous innovation - the <em>swerve</em> (<em>clinamen</em>), a tiny, unpredictable deviation in the fall of atoms that breaks strict determinism and makes room for free will.
Around 307 BC, in a garden on the outskirts of Athens, Epicurus founded a school of philosophy - the famous ‘Garden’ - and built it on a foundation of physics. Like Democritus before him, Epicurus held that the whole of reality consists of just two things: atoms (tiny, solid, indivisible, indestructible bodies) and the void (empty space). Nothing else exists in its own right. Everything we see - earth, sky, living things, ourselves - is a temporary assembly of atoms, formed when atoms collide and lock together, dissolved when they come apart. The atoms themselves are eternal and unchanging; they were never created and can never be destroyed; only their arrangements come and go. From this austere basis Epicurus undertook to explain the entire universe, with no gods directing it and no purpose guiding it.
Epicurus’ first principle, which he states at the very start of his physics, is the conservation of being: ‘nothing comes into being out of what is not, and nothing perishes into what is not.’ If things could come from nothing, anything could spring from anything, with no regularity; if things perished into nothing, the world would long ago have wasted away. But matter is conserved - the atoms persist through every change - and so nature exhibits stable order: each thing arises from suitable seeds and returns to its elements. On this firm ground Epicurus reconstructs the world. But he did not simply repeat Democritus. He inherited the atomic framework and then made one small but momentous change - a change designed to save something Democritus’ system seemed to crush: human freedom.
The swerve solves two distinct problems in atomic physics, and seeing both reveals its ingenuity. The first is a problem about collision. Epicurus held that, left to themselves, atoms fall through the infinite void in parallel straight lines, all in the same direction, ‘like drops of rain.’ (He disagreed with Aristotle that heavier things fall faster; in the void, he reasoned, all atoms fall at the same speed.) But here is the difficulty: if all the atoms fall straight down at the same speed in parallel lines, they would never meet - they would fall forever side by side, never colliding, never combining, and no world could ever form. Something must make them deviate so they can strike one another. That something is the swerve: a minimal, occasional sideways deflection that brings atoms into contact, starts the collisions, and so makes possible the entanglements out of which all things are built.
This is the opening of the lesson. The rest — the dialogue, the primary source, and the recall — is in the app.
You learned that Epicurus adopted Democritus’ atoms and void but added the swerve ( clinamen ): atoms falling through the void occasionally deviate by the smallest amount at no fixed time or place, which breaks rigid determinism, allows atoms to collide and form worlds, and leaves room for free will. Explain the swerv…
Leads to Democritus.
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