How do new tools and inventions affect societies? This question, which has become very topical in the face of a worldwide information explosion, was the perennial concern of Marshall McLuhan's career. Typically, he wanted to know the yet unseen ramifications of new technologies. The indirect consequences, the altering of our general environment, and consequently of our self-image in the society. His purpose was to understand media in their sociological, cultural and psychologial impact. To this end, he developed the Tetrad technique, which explores collateral effects of any technology. The Tetrad asks four questions about any human invention, or artefact, wheter it be physical object or system of thought. These questions are designed to underscore the possible effects of these inventions. What does the invention extend or amplify? What is its initial purpose? What invention or environment will it do away with or obsolesce? What older technology or environment will be retrieved from the past? What will the invention or tool or idea become when pushed to its limits? Philip Marchand's introductory essay begins with the account of one such artefact, the cell phone, and explains how the series of four questions appplies to it. The essay further explains the origins of the tetrad in McLuhan's thought, and how it came to be developed as a sophisticated technique of understanding technology. The Tetrad Workbook is a source for daily workouts in thinking like McLuhan. The idea is to become media savvy. Philip Marchand is the author of Marshall McLuhan: The Medium and the Messenger.
