McLuhan: teaching machines

There are many types of teaching machines. In general, they all work on the same method, which is to present a question, have the user indicate the answer, and then provide the user with the correct answer. Some machines may be extremely simple, such as test sheets or books so programmed that the student locates the answers to the questions later.

Echo Land

If so many reflections arrive at a listener that they are unable to distinguish between them, the proper term is reverberation. An echo can be explained as a wave that has been reflected by a discontinuity in the propagation medium, and returns with sufficient magnitude and delay to be perceived. Echoes are reflected off walls or hard surfaces like mountains and privacy fences.

Gutenberg Galaxy Mosaic

Vico conceives the time-structure of history as "not linear, but contrapuntal. It must be traced along a number of lines of development..." For Vico all history is contemporary or simultaneous, a fact given, Joyce would add, by virtue of language itself, the simultaneous storehouse of all experience