Interpretation on Marshall McLuhan’s ‘the tetrad’ diagram

Explain and give your personal interpretation on Marshall Mcluhan's the tetrad diagram.

In the Laws of Media(1988), written by McLuhan with his son Eric and published posthumously, he argues that tetrads are means of focusing awareness on hidden or unobserved qualities in our culture and technology. This follows from his argument that all human artefacts are human utterances or outer and such they are linguistic and rhetorical entities. At the same time the etymology of all human technologies is to be found in human body itself. They are, as it were, prosthetic devices, mutations, metaphor of the body or its parts. McLuhan argues that he effects of every media can be viewed in four ways, and that the tetrad offers an exegisis on four levels, showing the logos structure of each artefact and giving its four parts as metaphor or word. The tetrad is therefore a grid with four sections.

It explains that they further exhibit McLuhan's abiding concern with pedology; they are meant to be used as tools to analyze the patterns of effects that different technologies produce. McLuhan phrased them as questions with which to consider an artefact.

The idea behind the tetrad are explained in more details by Anthony Hempell. He describes

1. Enhancement

    - as the amplification of effects with a focus on the practical.It involves the creation of vortices of power and presents a solution to previous problem.

2. Retrieval

    -as the recovery of values and insight previously lost or eroded. It can involve the transition of ground to figure, that is the movement of a phenomenon from the periphery to the centre of attention.

3.Obsolescence 

   - as erosion of formerly significant artifact. This reverses the transition above causing a transition of figure to ground in which some previously important phenomenon is moved to the periphery.

4.Reversal 

   as the reverse of enhancement, the unexpected dissatisfactions. Pushed to its limits, the artifact flips    on its user and creates new problems.

To more understand about it, I watched the video above

References:

https://www.owenkelly.net/984/mcluhans-tetrads/

https://goo.gl/images/cxYvcE

https://www.youtube.com/watch?v=eRnexsrlSdA
https://goo.gl/images/3sfrvi