Generative Artificial Intelligence (GAI), as a technological innovation, is reshaping the education ecosystem, raising the risk of alienation such as homogenization of teaching design and cognitive homogenization while enhancing teaching efficiency, threatening the subjectivity and humanistic value of education. Technological intervention in education has gone through three stages: instrumental rationality, system integration and intelligent integration, which optimizes the supply of resources but intensifies the worship of data and algorithmic dependence, leading to the alienation of teacher-student relationships. The core function of teachers is rooted in the four constant kernels of teaching wisdom, value judgment guidance, emotional connection and humanistic innovation, which become the key to resist technological alienation. In order to realize the balance between technological empowerment and educational integrity, it is necessary to build a gradient control system, promote the double-helix professional development path that integrates technological literacy and educational wisdom, and follow the ethical governance guidelines of human nature first and cultural immunity, so as to safeguard the essence of education in dynamic adaptation and promote the sustainable development of human-machine synergy.