Here we will try to posit the relationships between vision, thought, spoken or “ signed ” languages and narcissism in adolescence, such as they are revealed by deaf-muteness. For any deaf person, vision is the object of an over-investment that is both saving and problematic. Its importance need not be stressed, but its preponderance raises some questions. The theory of the “ visual envelope of the ego ” enables us to posit the theoretical issues, and some excerpts from the psychotherapy of a hearing-impaired adolescent bear witness to the clinical issues : narcissistic suffering and the suffering of the thought process.