The essay will try to show that The House of Mirth can be read as a kind of experiment in which Edith Wharton uses her character Lily Bart to probe the mysteries of personal identity. A close study of the novel shows that Lily's ego can be apprehended at three separate levels : i) an openly social self based on plottings and calculations ; ii) a seemingly moral and idealistic inner self, on the face of it anti-social, but in reality extremely conventional ; iii) moments of non human, non individual and non social impulses that cannot be represented by words. It is that third level which interested a novelist dissatisfied by the society from which she comes, but who, however, in her own life, never fully identified with her character. The most important question Edith Wharton asks seems to be : how far can one go in order to be as little part of society as possible ? In particular, a study of Lily’s use of the semantic implications of two key words, luck and fate, will enable us to articulate the three components that make up her sense of self. What exactly is the lethal logic which explains how her attraction for luck (as well as for faith and friendship) systematically leads her to become the prisoner of what turns out to be her fate ?