Highlights from The Medium is the Massage by Marshall McLuhan (excerpted from https://designopendata.files.wordpress.com/2014/05/themediumisthemassage_marshallmcluhan_quentinfiore.pdf):

Societies have always been shaped more by the nature of the media by which men communicate than by the content of the communication. The alphabet, for instance, is a technology that is absorbed by the very young child in a completely unconscious manner, by osmosis so to speak. Words and the meaning of words predispose the child to think and act automatically in certain ways. The alphabet and print technology fostered and encouraged a fragmenting process, a process of specialism and of detachment. Electric technology fosters and encourages unification and involvement.

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Electric circuitry has overthrown the regime of “time” and “space” and pours upon us instantly and continuously the concerns of all other men. It has re- constituted dialogue on a global scale. Its message is Total Change, ending psychic, social, economic, and political parochialism. The old civic, state, and national groupings have become un- workable. Nothing can be further from the spirit of the new technology than “a place for everything and everything in its place.” You can’t go home again.

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The “child” was an invention of the seventeenth century; he did not exist in, say, Shakespeare’s day. He had, up until that time, been merged in the adult world and there was nothing that could be called childhood in our sense.

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Media, by altering the environment, evoke in us unique ratios of sense perceptions. The extension of any one sense alters the way we think and act— the way we perceive the world. When these ratios change, men change.

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The dominant organ of sensory and social orientation in pre-alphabet societies was the ear— “hearing was believing.” The phonetic alphabet forced the magic world of the ear to yield to the neutral world of the eye. Man was given an eye for an ear.
Western history was shaped for some three thousand years by the introduction of the phonetic alphabet, a medium that depends solely on the eye for comprehension. The alphabet is a construct of fragmented bits and parts which have no semantic meaning in themselves, and which must be strung together in a line, bead-like, and in a prescribed order. Its use fostered and encouraged the habit of perceiving all environment in visual and spatial terms—particularly in terms of a space and of a time that are uniform,
c,o,n,t,i,n,u,o,u,s
and c-o-n-n-e-c-t-e-d.

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Visual space is uniform, continuous, and connected. The rational man in our Western culture is a visual man. The fact that most conscious experience has little “visuality” in it is lost on him.
Rationality and visuality have long been inter-changeable terms, but we do not live in a primarily visual world any more.

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Until writing was invented, man lived in acoustic space: boundless, directionless, horizonless, in the dark of the mind, in the world of emotion, by primordial intuition, by terror. Speech is a social chart of this bog.
The goose quill put an end to talk. It abolished mystery; it gave architecture and towns; it brought roads and armies, bureaucracy. It was the basic metaphor with which the cycle of civilization began, the step from the dark into the light of the mind. The hand that filled the parchment page built a city.

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The technology of the railway created the myth of a green pasture world of innocence. It satisfied man’s desire to withdraw from society, symbolized by the city, to a rural setting where he could recover his animal and natural self. It was the pastoral ideal, a Jeffersonian world, an agrarian democracy which was intended to serve as a guide to social policy. It gave us darkest suburbia and its lasting symbol: the lawnmower.

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The “expert” is the man who stays put.

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“There are children playing in the street who could solve some of my top problems in physics, because they have modes of sensory perception that I lost long ago.”
—J. Robert Oppenheimer

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The ear favors no particular “point of view.” We are enveloped by sound. It forms a seamless web around us. We say, “Music shall fill the air.” We never say, “Music shall fill a particular segment of the air.”
We hear sounds from everywhere, without ever having to focus. Sounds come from “above,” from “below,” from in “front” of us, from “behind” us, from our “right,” from our “left.” We can’t shut out sound automatically. We simply are not equipped with earlids. Where a visual space is an organized continuum of a uniformed connected kind, the ear world is a world of simultaneous relationships.

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“The discovery of the alphabet will create forgetfulness in the learners’ souls, because they will not use their memories; they will trust to the external written characters and not remember of them- selves … You give your disciples not truth but only the semblance of truth; they will be heroes of many things, and will have learned nothing; they will appear to be omniscient and will generally know nothing.”
-Socrates, “Phaedrus”

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Most people find it difficult to understand purely verbal concepts. They suspect the ear; they don’t trust it. In general we feel more secure when things are visible, when we can “see for ourselves.” We admonish children, for instance, to “believe only half of what they see, and nothing of what they hear.” All kinds of “shorthand” systems of notation have been developed to help us see what we hear.

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The highest purpose is to have no purpose at all. This puts one in accord with nature, in her manner of operation.” -John Cage

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The invention of printing did away with anonymity, fostering ideas of literary fame and the habit of considering intellectual effort as private property. Mechanical multiples of the same text created a public—a reading public. The rising consumer-oriented culture became concerned with labels of authenticity and protection against theft and piracy. The idea of copyright—”the exclusive right to re- produce, publish, and sell the matter and form of a literary or artistic work”—was born.

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“Only the hand that erases can write the true thing.”
—Meister Eckhardt