Where is personality born? And how can our personalities exist in someone else's mind? Is the thought material? Are personality, soul, consciousness, "I" material? If not, how can we be here? Douglas Hofstadter argues that the key to understanding personality is the "strange loop," an abstract closed entity of a special kind contained in the brain. The main and most complex symbol is "I." This link is one of many symbols that seem to be endowed with free will and have gained the paradoxical ability to direct particles in the brain. So how can a mysterious abstraction be real? Or is "I" a handy fiction? Does "I" have power over other particles or does it obediently echo the laws of physics? The author fights over these riddles, for the first time since his magnum opus, who undertook an original philosophical investigation of the essence of the human mind.