τ₀ Stability Criterion: A Universal Law of Existence from Quantum Particles to Living Systems

All causal responses in the universe are constrained by a strictly positive minimum response time, τ₀. While this principle unifies the “form” of dynamic behaviors across physical, biological, and cognitive systems, we demonstrate here that it also governs their “substance”—the very condition for existence. We introduce the τ₀ stability criterion: a system can persist only if its intrinsic minimum response time is much shorter than its characteristic lifetime. This criterion explains why protons are stable, why DNA can store information over generations, and why conscious processes endure within neural dynamics. Furthermore, we propose a possible link between τ₀ and the Higgs field, suggesting that mass may arise as the inverse of fundamental response delay. Our framework thus connects dynamics and stability, form and substance, opening a path toward a unified understanding of existence itself.