The Freudian psychoanalysis in its modern form assumes that activities of a patient depend on his physical and mental state (“energy”), and result in maintaining his life, in useless waste of his energy (“symptoms”), and in (“useful”) contribution to the society and to patient's energy level.

Another contribution to patient's energy level comes from the society. It comprises life amenities, medication, and “education”. Patient's mental state is characterized by two parameters, “symbolic” and “imaginary”. Both parameters affect the outcome of patient activities, and are affected by contributions to his “energy”.

A mathematical description of this model as a dynamical system is presented. Significance of obtained solutions for psychoanalysis is discussed.