Exploration of the nature of human communication and the media is a pre­ requisite to any assessment of the likely future role of communications . . We cannot assume that the nature of these things is transparently obvious to everyone and therefore commonly understood. Three developments in recent decades should adequately warn against such an assumption. First, we had the fiasco of social scientists trying to apply Shannon's mathematical theory of information as if it were a theory of human communication. 'In Shannon's use of information we cannot speak of how much information a person has only how much a message has. ' (Ackoff and Emery, 1972, p. 145). They would not have wandered into that blind alley if they had stopped to think about the nature of human communication. Second was the belated but wholehearted acceptance of the Heider theory of balance and its subse­ quent wane. Its wane had nothing to do with its inherent merits. It waned because it could not survive on the Procrustean bed of the psychologists' theory of choice. It did not occur to the psychologists to question their as­ sumptions about how people made the choices that lead to purposeful com­ munication (Ackoff and Emery, 1972, p. 58). The last example has been the bitter and unended furore about McLuhan. This time the psychologists and sociologists haye been strangely quiet but we can be sure this does not imply acquiescence in McLuhan's views.