[The problem of truth in psychiatry]

Psychiatry has forgotten too early about the problem of truth (Zutt). In the first treatises on delusions, these are described as pathological errors, as mistakes in the ability to judge reality. For French psychiatry, delusions are false ideas of pathological origin, resistant to logical argumentation that alter the ability to judge reality, a concept still present in DSM-IV, in which it is defined as wrong beliefs that normality imply a wrong interpretation of perceptions of experiences. As a consequence, delusions are classified according to its contents. German psychiatry however seeks for the structures underlying to all delusions, some authors have even defended the notion of a single psychosis. The Heidelberg School, so well analyzed by Laín, developed a psychopathology which dismantled the notion of delusion then accepted (falseness is a relative and accessory notion and the lack of information plays an important role, as well as cultural and religious factors). K. Schneider describes the two forms of delusion: delusional perception and delusional occurrence. Both concepts have been criticized, therefore it is necessary to consider truth as a process and not as a state and to take into account the contributions of the philosophy of science and psychoanalysis. The concept of truth of Aristotle (the adaptation of the logos to the thing) is the one that has prevailed along history. But, for Heidegger the truth as aletheia (the process of revealing) is deeper and allows, applied to psychopathology, the connection of truth, liberty and relationship between human beings. As a consequence, the error of delusion, its lack of liberty, is also a lack of communication. The process of getting closer to truth is marked by an ethical attitude of tolerance.