The rule of free association, at the very basis of the psychoanalytic technique, implies from the outset a certain paradox, since it is only heuristic insofar as the succession of ideas verbalized by the patient is in no case free or arbitrary, but, on the contrary, very precisely determined by the truth of the unconscious. While it is true that Freud conceived of the existence of a strict psychic determinism, does not this conception nonetheless render any reference to the freedom of the subject in the analytic approach obsolete? By returning to the metapsychology of the trace, it can be observed that, although the registration of perceptual traces in the form of memory traces is the precondition of psychic determinism, this registration implies from the outset a discontinuity between experience and its registration, and opens the way for the expression of a certain freedom of the subject, reintroducing the dimension of the unforeseen at the heart of psychoanalysis.