Essential McLuhan 366 hardest, reading matter, they are precisely on the level at which the printed word can seize and convince them without opposition. They are perfectly adapted to propaganda.6 The dominance of the left hemisphere (analytic and quantitative) entails the submission or suppression of the right hemisphere; and so, for example, our intelligence tests exist only for measuring left-hemisphere achievement, and take no cognizance of the existence of the (qualitative) right hemisphere. 6 Jacques Ellul, Propaganda: The Formation of Men’s Attitudes, 108–9. Harold Innis comments on the moment of transition: “For a brief period the Greeks escaped from the oral tradition and the written tradition. The oral tradition was sufficiently strong to check complete submergence in the written. The oral tradition supported Greek skepticism and evaded monopolies of religious literature” (The Bias of Communication, 111). [From Chapter 3] LAWS OF MEDIA Sir Karl Popper’s (right-brain) statement that a scientific law is one so stated as to be capable of falsification made it both possible and necessary to formulate the laws of the media. All of man’s artefacts—whether language, or laws, or ideas and hypotheses, or tools, or clothing, or computers—are extensions of the physical human body or the mind. Man the tool-making animal has long been engaged in extending one or another of his sense organs in such a manner as to disturb all of his other senses and faculties. But having made these experiments, men have consistently omitted to follow them with observations: J.Z.Young, in Doubt and Certainty in Science, notes: The effect of stimulations, external or internal, is to break up the unison of action of some part or the whole of the brain. A speculative suggestion is that the disturbance in some way breaks the unity of the actual pattern that has been previously built up in the brain. The brain then selects those features from the input that tend to repair the model and to return the cells to their regular synchronous beating. I cannot pretend to be able to develop this idea of models in our brain in detail, but it has great possibilities in showing how we tend to fit ourselves to the world and to the world to ourselves. In some way the brain initiates