Marshall McLuhan

Understanding Media

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Understanding Media Summary

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Understanding Media: The Extensions of Man (1964) by media theorist and public intellectual Marshall McLuhan was a major work that helped inaugurate the field of New Media, which seeks to create ways of linking visual, aural, and functional design with other arts and sciences to reshape theory and public life. Much of McLuhan’s book is centered on his most famous assertion that “the medium is the message”; that is, the structure of the delivery system transmitting any given content is more important than the content itself. He exhorts other design theorists and public thinkers to focus on these transmission modes rather than what people might use them to say since the medium delimits a priori what it is possible to say.

McLuhan splits the book into two main sections. The first explicates a distinction between what he calls “hot media” and “cold media.” Hot media represent extensions of our physical capacities, refining or enriching them with a high density of information. In this category, he includes images and text, since they are dense with visual data processed by the eyes. Moreover, they are relatively unambiguous from an objective point of view, since the totality of information they present does not mutate.

In contrast, cold media extend physical capacities but do so by reducing the density of information. They require their audience’s active interpretation in order to be legible as intended. For example, the cartoon and television program are both cold media because the totality of the information they present is entangled in a time-lapse made up of countless frames (which were almost always in lower definition than professional photography at McLuhan’s time of writing). Curiously, despite presenting denser information, hot media are harder to learn from since they invite less participation, which produces recursive feedback. Cold media are easier to learn from because they consist of this more social, participatory, function.

Next, McLuhan provides the light bulb as an extreme example of a device that can be interpreted as a medium with absolutely no semantic content. The light bulb is itself a glass enclosure with a filament that reacts to electricity that flows from an outlet. It emits light waves; however, the light waves in themselves carry no information or message until they reach another medium, such as a solid surface. In this way, McLuhan argues, a light emitting device “creates an environment by its mere presence.” He goes even further, arguing that the content of television (as in the show it aired) does not really matter. Rather, television as a medium contains the totality of its effect on society. This argument is most often construed as, “the medium is the message.”

McLuhan spends the second section of the book analyzing different media in his present context, 1960s America, which he believes are important in form rather than content. Among these are the literary genres of oral and written communication, newspaper routes, roads and the physical traffic they contain, clothes, abstract quantities, vehicles such as the plane and bike, the institution of the press, weapons, and automated technological enterprises. He breaks down each of these media into what constitutes its form, isolating form from whatever content it might transmit. In effect, he shows that most of what we think of today as media, we have confused function and structure with the multitude of messages with which people inject them.

McLuhan ends by exhorting his audience to open their minds about the possibilities of invented media. Messages are not in themselves invented and, therefore, are not valuable without the structural aid of their transmission media. He emphasizes that the world is more capacious than we often assume, and hopes that a proliferation of new media will make his argument self-evident.