This study addresses the structural limitations of centralized, top-down reforms in Korea and the weakening of intrinsic change dynamics as teacher-led initiatives become standardized within institutional frameworks. It seeks to identify the inner force and philosophical foundation that sustain teachers’ practice and proposes a new reform model. The “Seonggi–Seongmul Fractal Model,” combining the Confucian concept of Seonggi–Seongmul (成己成物) from the Jungyong with Complex Systems Theory, interprets Seong (誠, sincerity) as a fundamental value uniting life and education. Seong functions as a normative force guiding reflection toward practice and appears through relational action (In 仁), reflection (Ji 知), and continuous enactment (Yong 勇). This fractal structure, repeating across the scales of classroom, faculty office, school, and institution, drives bottom-up transformation and recontextualizes Confucian thought within contemporary educational discourse by presenting a new philosophical foundation for sustainable, teacher-centered reform grounded in the generative dynamic of Seong (誠) emerging from love (In 仁) and resonating with the ontological rhythm of creation.