This work presents a innovative ontological framework centered on the primacy of differentiation, offering a profound rethinking of being, consciousness, and relationality. Drawing from philosophy, science, religion, and technology, the author articulates a layered model of reflexive differentiation (R0–R7), which charts the emergence of complexity—from biological individuation to ethical recognition of the other, and ultimately to the open, unfixed Game of difference. The text explores how differentiation operates as the fundamental structure underlying all forms of existence, from genetic codes and linguistic systems to social structures and artificial intelligence. It challenges traditional metaphysical paradigms by revealing that every act of differentiation is an expression of Potentiality—a groundless, inexhaustible source of possibility. Through interdisciplinary dialogues with major philosophical, scientific, and mystical traditions — ranging from phenomenology and structuralism to Buddhist and Daoist thought — the book invites readers to engage with difference not as separation but as a dynamic, creative force. The ontology of differentiation dismantles hierarchical and fixed frameworks, proposing instead a "Game" of infinite freedom where difference resonates without domination. This provocative study will appeal to philosophers, scientists, theologians, and technologists interested in the intersections of being, consciousness, and potentiality. It calls for sustained reflection on how we might attune ourselves to the ever-unfolding movement of differentiation, both within and beyond human experience.