“Man-made environments are always unperceived 
by men during their period of innovation. When 
they become superseded by other environments, 
they tend to become visible.” (1968, p.17)

McLuhan presented his ideas on how this worked 
for the introduction of the alphabet and the 
printing press in his 1962 book The Gutenberg  
Galaxy . But his most controversial 
pronouncements concerned the present. Take this 
from the introduction to Understanding Media :

“After three thousand years of explosion, by 
means of fragmentary and mechanical