disservice environments (they are 
complementary) created by these extensions of 
our bodies saturate our sensoria and are thus 
invisible. Every new technology thus alters the 
human sensory bias creating new areas of 
perception and new areas of blandness. This is as 
true of clothing as of the alphabet, or the radio.

Marshall McLuhan to Jacques Maritain, May 6, 
1969, Letters of Marshall McLuhan  , (Toronto, 
1987) p.369.