Through an archaeological study of the emergence of questions related to the principles the regulation of psychic functioning in the Freudian corpus, I will try to shed light on how the metapsychological notion of “life drive” emerged in Freud's work. It will become clear that, from their beginnings, Freud's theoretical considerations displayed a manifest degree of autonomy with regard to a strictly biological point of view. After looking at the physical foundations of Freud's epistemological model, and particularly the influence of the School of Helmholtz and the thermodynamic principle of entropy, I will turn to the modifications introduced by the definition of the life drive in 1920, in order to show how, far from rehabilitating a theory of living matter in Freudian theory, it enhances on the contrary the emancipation and autonomy of the metapsychological concept of the drive with regard to any biological considerations.