After three thousand years of explosion, by means of fragmentary and mechanical technologies, the Western world is imploding

McLuhan starts his writing with this rather determinist statement. He goes on to argue that the medium through which humans consume content is more pertinent than the content itself. This lends itself to a lengthy discussion on technology and the positive/negative impacts of it. McLuhan generally seems to disapprove of most forms of electronic technology, though he leaves some of it up to the reader to decide.

It is the persistent theme of this book that all technologies are extensions of our physical and nervous systems to increase power and speed.

McLuhan separates technologies into two categories: technologies that are designed to increase the physical capabilities of humans, and those designed to increase consciousness. He generally seems to approve of physical technology, such as bicycles. However, he looks down upon electronic technologies.

Our new electric technology that extends our senses and nerves in a global embrace has large implications for the future of language.

McLuhan theorizes that language is the original and most natural medium of media. He sees all other technologies as building off of human language.

Everybody experiences far more than he understands. Yet it is experience, rather than understanding, that influences behavior, especially in collective matters of media and technology, where the individual is almost inevitably unaware of their effects upon him.

Here McLuhan offers an explanation for why media studies has focused solely on content rather than medium. The medium is usually hidden or almost too outrightly obvious to the viewer. Viewers and scholars rarely even notice the medium through which they consume information. They are instead too distracted by the content.