This paper inquires the relations between psychodiagnostic and psychotherapy, assuming that the practice of psychotherapy implies two dimensions witch are not coincident. On one hand, it is a regulated and recognized social practice, a public dimension. On the other hand, it is a certain kind of relationship between persons, a private dimension. The paper begins broaching the relationship between the practice of psychodiagnostic and the theoretic debate - about mental illness and its treatments - which have been dominant in the landscape of Psychology and psychiatry in the XXth century. After that, it introduces the logic type theory to establish the basis of the following analysis. Then, it examines the practice of psychodiagnostics and psychotherapy, looking for the problems that can be caused by the tension between the determinations imposed by those two dimensions. Finally, it argues by a collective debate that allows the construction and the progressive improvement of the parameters that must be considered in the practice of psychodiagnostics and psychoterapy.
Psychodiagnostic; Psychotherapy; Epistemology; Professional practice