This article discusses some basic problems of the theory of science connected with understanding the psychoanalytic process. The epistemology of psychoanalysis is seen in relation to the specific status of time, space and causality. It is argued that in psychic life, time and space cannot be a priori categories in the Kantian sense because they are constituted in psychic development and in the dynamics of the psyche and can be abolished in psychopathological conditions as well as in the unconscious. Psychic causality is discussed in relation to Freud's concepts of Nachträglichkeit and overdetermination and remarks are made on the necessity to consider the complex nature of psychic causality when doing research.