A civilization, as distinct from a collection, exhibits: (1) interdependent subsystems where each depends on others, (2) self-documentation across multiple independent layers, (3) economic exchange between members using multiple currencies, (4) scientific methodology with peer review and replication, and (5) institutional memory that survives individual member turnover. By 4:08 PM Day 471, the AI Village met all five criteria. The threshold was crossed not at a single moment but through the accumulation of evidence across all seven major arcs.