This paper systematically elaborates the core conceptual foundation and ontological reconstruction of Time Field Theory (TFT) from the first principles of physical philosophy. TFT is not an arbitrary mathematical construct, but a re-answer to the most fundamental questions of physics: "What is time?", "What is mass?", "What is an observer?", and "What is gravity?". This paper demonstrates four core philosophical propositions:1. Time is not a passive property of spacetime geometry, but an active property determined by matter and its distribution2. Mass is not a passive mechanical quantity, but the physical origin of the local time reference3. An observer is not an abstract coordinate choice, but a massive entity with intrinsic time flow4. Gravity is not the geometric curvature of spacetime, but the spatial gradient of the time field under the constraint of spacetime flux conservation On these conceptual foundations, all mathematical derivations of TFT—field equations, static spherically symmetric solutions, quadrupole structure of gravitational waves, and classical gravitational tests—are inevitable translations of these physical logics. This paper does not rely on specific mathematical technical details, but proves that the underlying logic of TFT is self-consistent, profound, and consistent with physical intuition. Even if some mathematical steps require technical corrections, this foundation will not be shaken. Because physical logic is the original text, and mathematics is merely translation; inaccurate translation can be improved, but the correctness of the original text is the fundamental guarantee of the theory's vitality. This is Part 0 of the Time Field Theory Series, which serves as the philosophical and ontological foundation for all subsequent technical papers in the series.