WITHDRAWN

We demonstrate that all saturating response curves observed in physics, chemistry, biology, and social systems-including sigmoid, logistic, Michaelis-Menten, and exponential relaxation curves-can be naturally derived from the fundamental existence of a minimal causal response time 0 > 0. By formalizing the system as a causal low-pass filter with nonlinear input constraints, we show mathematically that any attempt at instantaneous response is physically forbidden, leading inevitably to saturation.The framework unifies previously empirical models under a rigorous physical and mathematical principle.