The aim of this paper is to reflect the differential clinical approach of psychoanalysis and neuroscience. The chosen method is the case-analysis and argumentation, that cames from the field of Law. Casuistry illustrates the obtained results. In conclusion, the concept of symptom is central to each clinical concept and it implies a differential that sets the field, structure and functions. The spread of science is a real difference, that does not figure, but it is capable of measuring. The spread of psychoanalysis is a symbolic difference, with its interpretation. This is not in opposition to the neurosciences or drugs, but to ask about its ethical status, derived from the primacy of the clinical position in the art of healing. The meeting point between neuroscience and psychoanalysis in the context of our time is characterized by the technological progress and the discourse of capitalism.