WHERE DOES HUMAN LIFE BEGIN? Toward a Zygote-Based Science of Humanity presents an interdisciplinary framework examining the continuity of human existence from the zygote stage onward. Integrating developmental biology, philosophy of mind, systems theory, consciousness studies, and epistemology, the work proposes a zygote-based paradigm for understanding human identity, continuity, organization, and consciousness. The book challenges fragmented developmental interpretations by arguing that human existence should be understood as a continuous organizational process rather than a sequence of disconnected stages. Through theoretical synthesis and conceptual analysis, it develops the “Yeter Model” as an integrative framework connecting biological continuity, emotional emergence, consciousness development, and human meaning structures. This work is intended for interdisciplinary researchers in philosophy, biology, cognitive science, consciousness studies, developmental theory, and related fields.