Any student of the social history of the printed book is 
likely to be puzzled by the lack of understanding of the psychic 
and social effects of printing. In five centuries explicit comment 
and awareness of the effects of print on human sensibility are 
very scarce. But the same observation can be made about all 
the extensions of man, whether it be clothing or the computer. 
An extension appears to be an amplification of an organ, a 
sense or a function, that inspires the central nervous system to 
a self-protective gesture of numbing of the extended area, at 
least so far as direct inspection and awareness are concerned. 
Indirect comment on the effects of the printed book is available 
in abundance in the work of Rabelais, Cervantes, Montaigne, 
Swift, Pope, and Joyce. They used typography to create new art 
forms.

     Psychically the printed book, an extension of the visual