Summary The article substantiates the possibility and meaningfulness of a coherent theoretical system for psychotherapy, as it is strived for in Gestalt Theoretical Psychotherapy and presented in several articles in this issue of the journal "Gestalt Theory". The necessity of consistency in the theoretical assumptions and concepts of a psychotherapy method is not derived from scientific considerations alone, but already arises from the elementary role of consistency in human life. This also results in the requirements for the consistency of theoretical (...) foundations of psychotherapy. It is not fulfilled in a mere internal, logical consistency of its models, but only in the actual fitting together with the critical-phenomenal and naive-phenomenal worlds of the therapists and their clients in the reality test of life. (shrink)