Ross Dawson just finished reading a 1998 biography of McLuhan and found the following:
One new thing I learned about in reading the book was what McLuhan called the Tetrads, or the “laws of the media”.
it stirkes[It strikes] me that these “laws” are actually highly relevant to strategic analysis of any industry which is undergoing rapid change. I still have to dig up the original material to interpret it properly, but the following is my loose interpretation of McLuhan’s Tetrads.
1. Any innovative technology enhances or accelerates some of what existed before.
[Q: What does it enhance or accelerate?]
2. Any innovative technology erodes or renders obsolescent some of what existed before.
[Q: What does it erode or obselesce?]
3. Any innovative technology retrieves something that has become obsolescent.
[Q: What does it retrieve that has eroded or become obsolescent?]
4. Any innovative technology, when pushed to the limits of its potential, reverses or flips into something entirely new.
[Q: What does it reverse or flip into?]
Link: Future Exploration Network.