A traditional look at general psychology is that of isolated areas of knowledge relating to its history, methods, description of separate psychic processes and individual characteristics. This is a typical functional approach as opposed to that of theoretical psychology as basis for "general psychology" whose subject is self-reflection of psychological science to clarify and study its categorical structure, its explanatory principles, key issues, with psychological cognition proper as specific activity. With interdisciplinary science data taken into account, theoretical psychology builds up its own portrait having a careful look at its past, present and future. Theoretical psychology is not just the sum of psychological knowledge repertoire. It is more than a mere aggregate of its components. No psychological theory could claim to be a theory common to psychological knowledge all told. Theoretical psychology aims at constructing the theory of theories of psychological cognition. Theoretical psychology distinguishes basic and metapsychological categories which present the most general and fundamental definitions embracing essential behavior and interrelations of the phenomena studied. Theoretical psychology can follow V. S. Solov'ev's metaphysical ideas. They look at entity transforming into phenomena which in their turn become higher level categories. This enables us to understand the way metaphysical categories can be seen in essential properties of basic categories. The entity-phenomena relation concept underlying categorical psychology system was formulated by the author in the middle of the sixties with it being further developed nowadays.