"Schizophrenic Grice" -- J. Wrobel, "Language and Schizophrenia" -- citing Grice -- Wrobel quotes from De Decker and Van de Craen (1987) who analyse schizophrenic utterances from the point of view of Griceian rationality-based theory of implicature

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Language and Schizophrenia - Pagina 19

Janusz Wróbel - 1990 

Schizophrenics, on the other hand, present peculiar forms of life which are contradictory to the patterns given by grammar. De Decker and Van de Craen (1987) analyze schizophrenic utterances from the point of view of Grice's(1975) ...