Chapter 1 The form of public discource in American culture has changed from print to image. How has the content also changed? Postman writes in order to discuss this question.

He offers examples of how medium controls message, including smoke signals, graven images, clocks, written alphabet, glasses, microscopes, IQ, and mathematics. These illustrate Marshall McLuhan , “The medium is the message.” (8)
The form of human conversation (“conversation” refers to all of the information exchanged and all of the techniques to exchange it) affects what is convenient to express. What is convenient to express becomes the content of culture. Therefore, the form of conversation affects the content of the culture. For example, a society that primarily uses smoke signals is not likely to discuss philosophy; it would take too long and be too difficult. In the same way, a person with an ugly body will not look good on TV and therefore not be elected President. One’s body is not relevant to one’s ideas when one is expressing them through radio or print. But on TV, visual imagery reigns. Therefore the form of TV works against the content of philosophy. Therefore you cannot do political philosophy on TV.
A new tool contains a new idea that goes beyond the tool itself. Eyeglasses corrected vision in the twelfth century but the idea that went beyond the glasses was that man could improve his body. The clock is another tool that contained a powerful idea. Before, time was a product of nature measured by the sun and seasons. Now, time is measured by a machine using minutes and seconds. The clock changed us into time-watchers, then time-savers, and finally time-servers. Thus, changing the metaphor for time changed how we view time itself.
The written alphabet is a different tool than the spoken. It changes the metaphor for speech from voice to something else. It freezes speech. It changes focus from the ears to the eyes. It then allows the grammarian, the logician, the rhetorician, the historian and the scientist to study it.
He closes the chapter with this logical progression: We converse about nature and ourselves in languages that make it convenient. We don’t see nature itself; our view of it is shaped by our language. Our languages are our media. Our media are our metaphors. Our metaphors create the content of our culture.

Chapter 2: "Media as Epistemology"
A great metaphor shift has taken place in the U.S, -- with the result that the content of much of the public discourse has become dangerous nonsense.
Before, under print, discourse was different in that it was coherent, serious and rational. Now, under the visual, discourse is shriveled and absurd.
Epistemology is about the origins and nature of knowledge. It takes in definitions of truth and the sources from which such definitions come.
Postman argues that definitions of truth are derived, in part, from the character of the media of communication through which information is conveyed -- in earlier times, print; and now, visual (TV and computers).
Postman argues that every medium of communication has resonance -- it has power beyond its first use, the power to direct us to organize our minds and integrate our experience of the world. He says that the bias of a medium "sits heavy, felt but unseen, over a culture" and uses three examples of "truth-telling" to explain.
3 warnings regarding media as epistemology:
1. Changes in media do not bring about changes in the structure of people's minds nor changes in their cognitive capabilities.
2. An epistemological shift probably won't include everyone and everything. TV does not have an entirely unchallenged influence.
3. A TV- based epistemology pollutes public communication and its surrounding landscape. It does not pollute everything.
Typography fostered the modern idea of individuality (but destroyed the medieval sense of community and integrtion); it created prose and made poetry into an elitist and exotic form of