This article presents a study on the productivity of the concept of negation for the psychoanalytical theory. If in Freudian works, we observe that the Logic exerts an important comparative paper, in Lacanian field, the Logic offers instruments to think the subject of the unconscious. The work takes, as starting point, two negation meanings, the negation of the contrary and the negation of the contradictory. These two meanings are analyzed in the logic and psychoanalytical fields. The article presents the Lacanian analysis of the Freudian concept of negation and the Logic concept of negation. The study reveals as Lacan produces a logic of the subject of the unconscious based on the modern logic.
Psychoanalysis; logic; negation
