A history of psychotic delusion's definitions

Objectives. - Over the last two centuries, the delicate problem of the definition of delusion in psychosis has risen. For a long time the duration of insanity delusion in all its forms was essentially described. In fact, these descriptions concerned forms, mode of expression, themes and contents regarding delusion. Nevertheless, many authors have attempted to provide definitions and others have claimed that it was difficult or even impossible to define delusion. From delusion as an "error" to delusion as an "cure attempt" (Freud), there has been a very long clinical and theoretical highway. Methodology and results. - In this paper, we will show how over the past two centuries since Esquirol delusion's definition has evolved in psychiatry, and how, notably with Freud, delusion cannot be considered only as an error of judgment, a false argument, an illness, but more like a "subjective effort", intense "organization" and construction work (Falret) that allow the psychotic subject to protect him/herself against the unbearable. Discussion and conclusion. - In this manner, new delirious significations can provide a sort of "guide" in the life of the psychotic person, and permit building new links with reality. It is also with Freud and psychoanalysis a re-introduction of the "subject" in delusion and psychosis in general. So, before arriving to the question of "sense" in delusion, and the "function" delusion could have for the subject, we'll go through two centuries of psychiatry. This would appear essential for anyone who wants to study delusion in psychosis. (C) 2014 Elsevier Masson SAS. All rights reserved.