The Letter, Issue 18, Spring 2000, Pages 22 - 34
TO SPEAK ABOUT WHAT'S INVOLVED IN THE PSYCHOANALYTIC ACT,
ONE HAS TO SPEAK ABOUT LOGIC
Patricia McCarthy
Introduction
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.