Marshall McLuhan has the peculiar notion that television has very strange properties which set it apart from almost every other medium that human beings have ever used for communication. He holds rather para-doxically that television, in spite of its name, is not a visual medium at all but what he calls an audio-tactile medium. This is based on a rather spurious argument of his to the effect that the linear structure of the screen is similar to the movement of the hand feeling a page of Braille, that the electron beam scans the surface of the images which it is transmitting in a manner very similar to the movement of a hand scanning a line of Braille, and that therefore it is a tactile experience.
Now this seems to me to be conjuring a metaphor into a concrete proposal which I think is entirely false. It is perfectly true that television is made up of a beam which scans over several hundred lines, but the fact that the actual movement is a scanning movement and that the movement of a hand scanning the page is a scanning movement doesn’t mean that television is to be subsumed under the general category of a tactile experience. It simply means that the tactile and the visual modalities employ identical techniques when exploring a contour, and this was realized a hundred years ago by the English neurologist Hughlings Jackson, who said that no one ever saw anything without moving his eyes, or felt anything without moving his hands. All that McLuhan has pointed out is that no sensation ever reaches any sort of status in the nervous system until some sort of active negotiation between the agent and the environment has taken place.
Some very interesting experiments were done at Reading University about ten years ago, in which a contact lens was fixed onto the eye and a small mirror was attached to the contact lens so that a beam of light that was reflected from the surface of the eye onto a little screen was bound to move with every movement of the eye and the eye could not escape it: the same spot of light always fell on the same place in the retina. The investigators discovered that when this fixed retinal image was produced it would after a while fade until it was no longer seen, making it apparent that it is absolutely necessary to keep the eye on the move in order to see things. But this doesn’t make seeing into a tactile experience. The television screen is exactly like any other visual image that is on the move.
There are, of course, differences between the television image and the image on a movie screen, but they are not fundamental: they are simply quantitative differences of accuracy, of focus and grain. It’s true that the image on the television screen is on the whole much foggier than the image that you get either from a still photograph …