Schizophrenia is an impossible concept. It is used to summarize a group of psychoses which have in common that consciousness usually (not even always) remains unclouded during their course. No other common characteristics have been demonstrated in terms of symptomatology, aetiology or prognosis. There are therefore hardly any sound reasons to bring these syndromes under a single common denominator such as 'schizophrenia' or to refer to them as a 'group of schizophrenic psychoses'. It seems more likely that schizophrenic psychoses are separate entities — not variants of one basic form. What we need above all at this time is empirical research in an effort to chart the schizophrenia concept. Such a charting effort would have to start with carefully defined syndromes, and should then investigate whether, apart from symptoms, there are other features which characterize a particular syndrome, e.g. aetiology, pathogenetic factors, course or response to therapy. The more such characteristics can be found, the greater the chance that we are dealing with a separate entity. Pending such studies, and in order to avoid terminological chaos, it seems advisable for the time being to maintain the term 'schizophrenic psychoses' for practical purposes, provided that the designation in each actual case be supplemented with an accurate profile of the symptomatology, aetiological factors, and course.