This text provides a detailed analysis of the fundamental flaws inherent in both materialism and idealism, identifying reductionism as their primary shared error. The author argues that both philosophical schools commit an illegitimate reduction by either collapsing ideas into matter or matter into ideas. However, the core of the criticism focuses on the ontological conception of these foundational categories. In both systems, material particles and spiritual ideas are traditionally understood as static objects or substances. This approach leads to the direct negation of their essential temporality and event-like nature. The text emphasizes that ignoring the processual character of being prevents an adequate understanding of reality. Instead of viewing the world as a collection of fixed entities, the author suggests accounting for the dynamic dimension of existence. This perspective reveals that reality is not composed of immobile objective substances but is continuously formed within time and through events, necessitating a fundamental reassessment of traditional metaphysical foundations and their subsequent developments within modern philosophical thought.