The natural sciences provide highly successful laws and models describing processes in mechanics, thermodynamics, electromagnetism, chemistry, and biology. These laws, however, typically explain how processes unfold rather than why motion, interaction, and change arise at all. This paper proposes the Law of Tendency Toward Equilibrium as a universal conceptual principle. According to this law, all natural processes emerge only in the presence of imbalance and proceed in a direction that reduces or eliminates that imbalance. The paper argues that this law is not a human-constructed theory but a descriptive generalization of a stable and recurrent pattern observed throughout nature.