McLuhan

Marshall McLuhan... elucidated the ways our technologies at once strengthen and sap us. In one of the most perceptive, if least remarked, passages in Understanding Media, McLuhan wrote that our tools end up "numbing" whatever part of our body they "amplify." When we extend some part of ourselves artificially, we also distance ourselves from the amplified part and its natural functions.

When the power loom was invented, weavers could manufacture far more cloth during the course of a workday than they'd been able to make by hand, but they sacrificed some of their manual dexterity, not to mention some of their "feel" for fabric. Their fingers, in McLuhan's terms, became numb.

Farmers, similarly, lost some of their feel for the soil when they began using mechanical harrows and plows. Today's industrial farm worker, sitting in his air-conditioned cage atop a gargantuan tractor, rarely touches the soil at all—though in a single day he can till a field that his hoe-wielding forebear could not have turned in a month.

When we're behind the wheel of our car, we can go a far greater distance than we could cover on foot, but we lose the walker's intimate connection to the land.

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In explaining how technologies numb the very faculties they simplify, to the point even of "autoamputation", McLuhan was not trying to romanticize society as it existed before the invention of maps or clocks or power looms. Alienation, he understood, is an inevitable byproduct of the use of technology. Whenever we use a tool to exert greater control over the outside world, we change our relationship with the world. Control can be wielded only from a psychological distance.

In some cases, alienation is precisely what gives a tool its value. We build houses and sew Gore-Tex jackets because we want to be alienated from the wind and the rain and the cold. We build public sewers because we want to maintain a healthy distance from our own filth. Nature isn't our enemy, but neither is it our friend.

McLuhan's point was that an honest appraisal of any new technology, or of progress in general, requires a sensitivity to what's lost as well as what's gained. We shouldn't allow the glories of technology to blind our inner watchdog to the possibility that we've numbed an essential part of our self.