Current understanding of schizophrenia comes from Kraepelin’s dementia praecox doctrine, a disease that combined Kalbaum’s catatonia, Hecker’s hebephrenia and chronic delusional psychoses and later renamed to schizophrenia thanks to Bleuler. Since the beginning of the XX century, the systematics of schizophrenia has undergone a serious evolution and narrowing of diagnostic boundaries, which is reflected in various revisions of the ICD and editions of the DSM. Currently, the existence of non-psychotic forms of schizophrenia, mainly manifested by negative symptoms, is being questioned. In addition, the need for diagnostic differentiation of schizophrenia from autism spectrum disorder, which have only external similarities, but require fundamentally different therapeutic interventions, is emphasized. © Eco-Vector, 2024.