In the article an idea is pulled out that cause of absence of unity of psychological science is abandonment from the natural method of psychology - introspection. It becomes firmly established that self-evidence of internal experience at R. Descartes is investigation of coincidence in the introspection of gnoseology and ontology, act of knowledge and act of being. Organic, undistorting character of introspection is educed at understanding of psyche, as apperception (which will realize understanding of psyche as the definitely organized internal work, i.e. psychical determinism) guided by a mechanism. The mechanism of apperception means a presence in the psyche of initial heterogeneity, multiplicity, quasi-poly-subjectness. In this connection the problem of effective introspection is examined as a problem of effective communication of the variety-dimensional, variety-coordinate spheres of psychical apparatus of man, adequate internal transmissions of experience and adequate internal translations.