"The Greek myth of Narcissus is directly concerned with a fact of human experience, as the word Narcissus indicates. lt is from the Greek word narcosis or numbness. The youth Narcissus mistook his own reflection in the wat er for a not her person. This extension of himself by mirror numbed his perceptions until he became the servomechanism of his own extended or repeated image.( ... ) He had adapted to his extension of himself and had become a closed system".
Marshall McLuhan, The Gadget Lover, Narcissus as Narcosis, Chapter 4, Understanding Media:
The Extensions of Man (1964)