In the four years since making the above observations I have discovered very many
things about media and education. It is now perfectly plain to me that all media are environments. As environments, all media have all the effects that geographers and biologists have associated with environments in the past. Environments shape their
occupants. One person, complaining about my observation that "the medium is the message," simply said: "McLuhan means that the medium has no content." This remark was extremely useful to me because it revealed the obvious, namely, the content of any medium is the user. This applies equally to electric lights, any language whatever, and, of course, housing, motor cars, and even tools of any sort. It is obvious that the user or content of any medium is completely conformed to the character of this man-made environment. His entire sensory life arranges its hierarchies and dominance in accordance with the environment in which he operates.