A phenomenological-psychopathological approach, which attempts to directly explicate the basic mode of existence of affected persons, had once attracted broad attentions. Even today the most basic phenomena of schizophrenia cannot be understood without considering this approach, which takes current philosophies into consideration.

After the revolutionary work of Blankenburg, phenomenological psychiatry has attempted to elucidate the relation between transcendental constitution and “naturalness (Selbstverständlichkeit)” based on Husserl's notion of passive synthesis. However due care must be taken with regard to the current trend to lump together this synthesis with the latest neurophisiological findings.

Wittgenstein's philosophy, which turned from solipsistic analysis to the analysis of the language game in our daily life, has also contributed to understanding the quasi-solipsistic feature of delusions (Sass). One can also disclose, referring to Wittgenstein and Spensor-Brown, the specific feature of the conflicts between schizophrenic individuals and their hallucinatory voices. It is as if these conflicts could not be remedied without introducing “imaginary” numbers for solving equations.

It can be postulated that the “other” which once appeared and withdrew in the past, which one cannot retroactively conceive of, provides one with basic trust and the basic structural categorization of our world. However, in schizophrenic cases, this “other” appears in the real biography in the later stage, as someone who becomes the origin of trauma. Deleusian philosophy may make clear “the logic of life” of these individuals remaining in the pre-structured world and also may reveal the conditions of “our” experience from a “schizophrenic” perspective.