Laws of Media and Body Politics

Our environments are not passive wrappings, as our technologies are not passive tools — they are active actors that shape our world.

McLuhan, M., & McLuhan, E. (1992). “Tetrads.” In Laws of media: The new science. Toronto: University of Toronto Press.


Laws of media, technologies, media, artefacts, tetrads (enhancement, reversal, retrieval, obsolescence)


McLuhan uses the four laws of media, framed as appositional questions, to understand the actions and effects that technologies and artefacts exert on the human mind. McLuhan frames the questions of enhancement, obsolescence, retrieval, and reversal in a tetradic schema to observe the effects of various technologies on the psyche.


“Our laws of media are intended to provide a ready means of identifying the properties of and actions exerted upon ourselves by our technologies and media and artefacts” (98).

“All human artefacts are extensions of man, outerings or uttenngs of the human body or psyche, private or corporate. That is to say, they are speech, and they are translations of us, the users, from one form into another form: metaphors” (116).

“Whereas mechanical forms extend the limbs and organs, electric technologies beginning with the telegraph extend the nervous system and the conscious and unconscious in one or another manner and degree” (117).


McLuhan’s laws of media rely on the concept that media, artefacts, and technology have inherent properties that are impressed upon the user and change them. McLuhan examines the effects of technology on the user by posing the four laws of media as questions, with observable outcomes. Of a piece of technology, he asks the following:

1. What does it enhance?

2. What does it displace, replace, or make unnecessary?

3. What previous actions are repeated in the new form?

4. What inherent characteristics are reversed when the technology is pushed to the limit?

McLuhan views technologies as metaphorical extensions of the body and psyche, that alter the body and psyche. Applying a simple tetradic approach to the technology of a gun, one might observe the following:

While this example is rudimentary (McLuhan examples can be difficult to follow) and its statements can be expanded upon or argued with, the construct makes the case that the technology of the gun as an extension of the human body has a clear impact on the body politic. The human psyche changes; the way a person sees themselves in the world changes with this technology.

A gun may enhance the perception of personal security, while diminishing the perceived need for group security (state security). The actions are complementary. While the gun is a literal extension of the body, it is also an extension of the central nervous system, as it changes the way a person views the world in relation to the body. Technology, artefacts, and media are not passive objects, reflective only of our own nature through our use, but rather they impose their own inherent nature upon us when we use them, with practical effects on our own actions and thought processes.


McLuhan spends some time detailing the complementary actions of enhancement and obsolecence, with less discussion of retrieval and reversal aspects of his tetrad. I’d benefit with a more in depth discussion of these in class — Maybe this can be prompted with more discussion of the gun example used in the Commentary section. Using a gun as the technology, what are some more examples with explanations of retrieval of earlier actions in a new form and reversal of inherent characteristics?

In the example below, Homer Simpson buys a gun. Using McLuhan’s tetrad method, what does the gun do to him?


The Waiting is the Hardest Part

More Quotations

“This tetrad of the effects of technologies and artefacts presents not a sequential process, but rather four simultaneous ones. All four aspects are inherent in each artefact form the start” (99).

“Enhancement and obsolescence are obviously complementary actions” (99).

“Obsolescence is not the end of anything, it’s the beginning of aesthetics, the cradle of taste, of art, of eloquence and of slang, that is, the cultural midden-heap of cast-off clichés and obsolescent forms is the matrix of all innovation” (100).

“The needs of the poet, musician, and artist for ever-new means of probing and exploring experience send them back again and again to the rag-and-bone shop of abandoned cliché” (100).

“Etymology reveals a process of transformation of culture and sensibility and is also a matter of retrieval and of structure: the ground pattern of forces at the levels of molecular and atomic structure (116).

“Made discarnate by our electric information media the West is furiously at work retrieving its obsolesced organic first nature in a spectrum of new aesthetic modes, from feminism to phenomenology” (116).