I propose the Principle of Five: five is the minimal cardinality of a stable symbolic and structural representation of a complete identity. A complete identity is a system that maintains coherence across distinguishable expressions through a unifying center connected to those expressions by a relational mechanism. I show that numbers one through four each fail a distinct necessary condition, and that five — a center node connected to four expression nodes (K_{1,4}) — is the first configuration satisfying all conditions simultaneously. The framework maps onto the human framework of mind, body, soul