Schizophrenia, logicality and first-person perspective

The delirium of schizophrenia is marked in psychiatry as one of the most radically deviant forms of thought. It is also very often apprehended based on the analysis of verbal productions (scales, tests, experiments) and the speech of patients. Should we consider that insanity means a complete loss of logicality or rationality? Does assuming it help to understand schizophrenia? In this paper, we shall defend the reverse. From a discussion on the principle of charity, we address the question of rationality and logicality of schizophrenics and their understanding in a general philosophical perspective. We then present a work, based on this assumption of logicality, on the formalization of schizophrenic conversations. Some conversational "failures" are clearly typical of the pathology, and their theoretical account raises the question of their localization: shall one locate the breaks either at a logico-semantic, or at a pragmatic and interactional level? The analysis leads us to admit the two answers as reflecting two possible views on the conversation disease: the external or third person perspective, i.e., that of the "normal" subject, and the internal or first person perspective, specific to the schizophrenic. The formal analysis is conducted within the framework of Segmented Discourse Representation Theory of Asher & Lascarides, whose principles are briefly outlined in the article. (C) 2012 Elsevier Masson SAS. All rights reserved.