This thesis deals with the cause of the fall of the teachers’ right, which was revealed by a series of teacher deaths, from the complex perspective of the cause and diagnosis, rather than falling into the trap of turbid political camp logic. In other words, by shifting the discourse of the fall of teaching authority to the dimension of pedagogical reflection, the philosophical issue of the teacher's existence(Lehrer-Sein) was examined and the cause of the problem was diagnosed through the contrast with the social reality, In order to understand this problem, this article first attempted to conduct a philosophical preliminary examination of the relationship between the existence and duty of teachers, and as a result, it was confirmed that its existence and duty are excessively dominated by teleological-ontological philosophical discourse. Existence and duty are in a non-symmetry relationship due to heterogeneity and semantic imbalance that are not conceptually similar to each other. As I believe that this problem is closely related to various changes in social reality, I analyzed it focusing on four core themes: the collapse of modern teacher Image, the dilemma of educational correctness, the contradictory consequences of functionalization and legalization of life world(Lebenswelt) like school, and the anti-intellectualism trend of society.