Abstract
The epistemic processes leading to a practically viable “knowledge” in psychopathology are traced back from the transcendental-philosophical premises and antecedents through various epistemic steps to the empirical recognition and systematisation into a scientific theory. Psychopathology should serve empirical procedures in diagnostics, epidemiology, etiological conditions. However, it should also produce viable advices for the interpersonal therapeutic transaction. This is illustrated by an example of a catatonic syndrome.