McLuhan finds the visual bias of Western culture to be an effect of the phonetic alphabet.

In 'Culture Without Literacy' (1953), he suggests that writing enables some 'control of space'.1

In 'The Effect of the Printed Book on Language in the 16th Century' (1957), he says that 'Writing was a huge technological advance ... It expressed, it made explicit, many relations which were implicit .... And what writing couldn't make explicit, quickly got lost.'2

The effects of phonetic reading and writing, he says in 'Printing and Social Change' (1959), include 'psychic withdrawal, a weakening of sensuous life and a considerable lessening of the power of recall'.3

With the phonetic alphabet, 'men discovered how to translate the multi-sensuous thing that is spoken, language into one sense only.... abstract[ing] one sense [i.e. the visual sense] from the cluster of the human senses.'4

The phonetic alphabet, moreover, is the only writing system by means of which such dissociation is possible, reducing speech 'to a merely visual code'.5

Says McLuhan, 'Only the phonetic alphabet makes a break between eye and ear, between semantic meaning and visual code; and thus only the phonetic alphabet has the power to translate man from the tribal to the civilized sphere, to give him an eye for an ear.'6

In Laws of Media the McLuhans provide three justifications for this argument. Firstly, they say, the invention of the 'consonant' as 'a meaningless abstraction' enabled the visual sense 'to detach itself from the other senses' in the first place.7

Quoting Eric Havelock, they note that while the vowel 'could exist by itself in language, as in exclamations like "Ah."', the consonant could not; 'It was therefore an abstraction, a non-sound, an idea in the mind.'8

The phonetic alphabet was 'the first system in which in all cases one and only one acoustic value was theoretically attachable to one given shape'.9

The signs of the alphabet are thus rendered 'free of ambiguity', a feat that the McLuhans say 'was accomplished both by one-to-one matching of sign and sound, and by rendering the signs themselves inherently meaningless'.10

The second effect of the alphabet, the McLuhans say, is that it stresses the aspect of visual linearity, enabling us 'to transcribe any language into a series of abstract, meaningless sounds'.11

Thirdly, in its use, the phonetic alphabet promotes the 'suppression' or 'interiorization' of all the other senses except the visual sense 'as a guarantee of abstract, static uniformity', thereby producing a 'split between conscious and unconscious'.12

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