Having lost his father at the age of two, Hume later underwent an adolescent crisis that lasted for five years. He experienced a marked identity diffusion as well as various psychosomatic symptoms, including excessive salivation. The resolution of the illness involved his dedicating himself to his philosophic speculation and his living a life of personal detachment. In his early Treatise of Human Nature he argued that personal identity was a fiction. His concept of self was that of a "bundle or collection or different perceptions … in a perpetual flux and movement." Dussinger turns to Greenacre's thoughts about the family romance of the gifted to explain Hume's paradoxical "involvement" with detachment. He suggests that Hume denied the intensity of his internal tie to mother by opening himself up to a larger and impersonal collective of ideas and people. With this shift in orientation, he shut down his potential for relations with other persons. These notions are compelling but demand a Hume-like skepticism because of the paucity of biographical data offered.