The Lost Tetrads of Marshall McLuhan, by Marshall McLuhan and Eric McLuhan

Marshall McLuhan was the visionary theorist best known for coining the phrase "the medium is the message." Shortly before his death, together with his media scholar son Eric, McLuhan worked on a new literary/visual code — almost a cross between hieroglyphics and poetry — that he called "the tetrads." This was the ultimate theoretical framework for analyzing any new medium, a koan-like poetics that transcended traditional means of discourse. Now Eric McLuhan has recovered all the "lost" tetrads that he and his father developed, and accompanies them here with accessible explanations of how they function.