Thanks to the analysis of delusional perception's formal binary structure, generations of psychiatrists believed that the problem of delusion, at least from a descriptive point of view, had been resolved. The first-rank Schneiderian symptoms, and delusional perception in particular, had become reference points for the diagnosis of delusion and schizophrenia. Today, however, the phenomenon of delusional perception no longer seems to be taken into serious consideration by psychiatrists and psychopathologists. The crisis of the nosographic specificity of Schneiderian first-rank symptoms and the development of a transnosographic perspective in the study of delusion have definitively loosened the ties that existed in traditional psychopathology between delusional perception, delusion and schizophrenia. Despite the fact that delusional perception has lost its fundamental role in the nosographic sector, it still maintains its importance when studied in an interpersonal context. The significance of formal discontinuity evident in delusional perception authorized the psychiatrist to pause on the threshold of delusion without making allowances for the disastrous lack of comprehension so typical of delusional perception, which in turn must be studied from an interpersonal perspective, not as if it were an aseptic object in a laboratory. The therapeutic relationship can therefore provide an opportunity to recuperate those experiences which the patient was unable to store in his memory and concentrated in delusional perception.