Standing in the midst of this great historical change, as sometimes it is called the switch to the "post-modern", we are now confronted with the demand of paradigm change in every field of scientific knowledge. So it is the case with psychiatry. Just about 100 years ago, the trend of "social defense" (society's need to be protected from harm) was going on covering the whole civilized countries. It brought about a situation that could be generalized as "institutionalism" which made mental hospitals huge and custodial, resulting in the prevalence of nihilism with regard to treatment. It was just at this time that Dementia praecox, the preconcept of Schizophrenia, was formed by Kraepelin, E. (1896) as a mental disease resulting in peculiar dementia. After some period, Dementia praecox was transformed into Schizophrenia (Gruppe der Schizophrenien) by Bleuler, E. (1908) with a new methodology: to grasp the disease from the symptomatic viewpoint. Jaspers, K. (1912) as well as Schneider, K. (1938) followed him in the way that was psychopathologically more strict; the latter reached the formulation of the <symptoms of 1st rank>. Despite this eventful metamorphosis of the concept of Schizophrenia, its fundamental traits have remained unchanged until the late 1960's. They could be summarized as follows: 1) What patients mention is incomprehensible; 2) The prognosis leads to peculiar dementia; 3) The real cause of the disease is the brain disorder. These three are the reflection of the custodialism, curative nihilism and materialism through the institutionalized mental hospitals in those days. Now, since the 1970's, the situation has been completely changed, or at least, faced with inevitable changes. The tide of "deinstitutionalization" is covering all over the civilized countries, demanding the normalization of mentally disordered persons. Thus, deprived of its motherland (i.e. institutionalism), the concept of Schizophrenia has got into confusion or even crisis. And in order to relieve this confusion, severe attempts are internationally being made to identify the diagnostic criteria of Schizophrenia by means of what they call "operational diagnosis". I believe, however, that what is truely necessary is not such a compromising modification, but a more radical change that is: the DECONSTRUCTION OF SCHIZOPHRENIA.