Noting a distinct pattern in student teachers’ self-depreciating thoughts and behaviors around the same time of student teaching each year, the author conducted a qualitative study to figure out what was potentially contributing to this phenomenon. Wanting to have a better understanding of the unknowable or unsayable aspects of the student teachers’ emotional breakdowns and their teaching identities that were conceivably (re)negotiated, Lacanian psychoanalytic literature was referenced. While three pedagogical fantasies evolved from the study, only the most common and (re)current fantasy of the knowledgeable (art) teacher, the subject-supposed-to-know, is addressed within this paper. The author defines the subject-supposed-to-know and considers where and how this pedagogical fantasy is perpetuated. Suggestions are offered for art teacher educators to provide a supportive space to facilitate dialogue that is conducive to positive and realistic identity (re)formation of art student teachers.