On the largest and the smallest scale there is immutability: the universe is the sum of infinite space and an infinite number of atoms, and nothing can be added to it or subtracted from it; and each single atom is immortal, indivisible and indestructible. In between, everything is activity and mutability, for the atoms are in ceaseless energetic motion. The drama lies in this combination of change and changelessness, and Lucretius’ erotic metaphor celebrates this grand paradox.
