Sorry you have no rights to view this entry! Username: Password: Remember me Lost your password? Downloads Freud, S (1911). Formulations of the Two Principles of Mental Functioning, On Metapsychology, the theory of Psychoanalysis. S.E.14, or Penguin Vol 11 Freud, S (1915) Instincts and their vicissitudes. On metapsychology, the theory of Psychanalysis. SE 14, or Penguin vol 11.