This paper suggests that freudian theories regarding anxiety carry the imprint of the functionalism paradigm due to Freud’s deep insertion into the field of evolutionary biology at the end of XIX century. Neverthless, here as well as in other aspects, the psychoanalytic research has lead Freud to break up with some of the premises of the functionalism paradigm. Basically the importance of adaptation, of the tendency to auto-equilibrium, of temporality conceived as evolution and development should be undermined when a more careful consideration of anxiety in human experience takes place. It is at this very point that the contribution of philosophers like Heidegger and Lévinas can be valuable so that some perspectives already perceived by Freud may show in psychoanalitic practice and theory, perspectives which would not become visible while the functionalism paradigm would predominate in psychoanalytic thinking.