This paper analyzes Foucault’s early thinking (from 1954 to 1957) as it bears on psychology, anthropology and psychiatry. The author maintains that Foucault’s texts from that period can be mined for the origins of the Foucault methodology, early indications of its scope, and its first applications. Although Foucault opposed a phenomenology of epistemology and allied himself with the latter, a close reading of his early work reveals a paradoxical synthesis of phenomenological and epistemological views. The influences of Georges Canguilhem, Maurice Merleau-Ponty, and Ludwig Binswanger were decisive here.Foucault adopted the “practice-to-theory” vector from Canguilhem and grounded the history of psychology and psychiatry on the study of essential oppositions: normal - pathological, personality - environment, evolution - history. Merleau-Ponty’s theory allowed him to demonstrate that the ontological perspective of psychology and psychiatry does not match the subject of their research, which is the person and thei