THE LETTER 18 (Spring 2000) pages 22-34
In the course of Seminar XIV The Logic of Phantasy and Seminar XV The Psychoanalytic Act Lacan takes his project for a science that includes psychoanalysis to new heights. Using a deMorgan-like transformation he establishes a truth equivalence between Descartes ‘I think therefore I am and his own axiom for the subject of lack ‘Either I do not think or I am not.
Beginning with negation and contradiction, this paper looks to underscore the inadequacy of classical logic to account for the subject of the unconscious. This sortie into logic continues with an examination of the ‘innards’ of the deMorgan law ~(C&D) =11= (~Cv~D) as employed by Lacan. The paper concludes by referring to the pivotal function of the disjunction ‘Either I do not think or I am not’ for Lacan’s conception of the psychoanalytic act as a logical operation that can only be decided by a logically realised end to analysis itself.
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Lacan’s teachings are shot through with logical argument as are Freud’s texts. Both were highly fluent in the argument-forms of classical or propositional logic. However, in the case of Lacan, it wasnt until 1964 with Seminar XI – The Four Fundamental Concepts of Psychoanalysis – that he systematically began to formulate a logic, specific for psychoanalysis, which would account for the subject of the unconscious. With this logic of psychoanalysis, his aim was, not to establish whether or not psychoanalysis is a science, but to establish the nature of a science that…