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The difference lies in the control systems. The sewing machines, clothes dryers, and turboprops of the 1960s used relatively simple mechanical means of control, guided by the skill of human operators. Their equivalents today use complex digital electronics, courtesy of the computer revolution, and require much less human skill to run effectively. On a 1960s sewing machine, for example, buttonholes are sewn using a simple mechanical part and a great deal of knowledge and coordination on the part of the seamstress; on a modern machine, as often as not, the same process is done by tapping a few virtual buttons on a screen and letting the machine do it. Changes of this sort are generally considered signs of progress. This easy assumption, though, may require a second look. It’s true that the primitive computers available in the 1960s would have had a very hard time sewing a buttonhole, and the idea of fitting one of the warehouse-sized mainframes of the time into a home sewing machine would have seemed preposterous; computer technology has certainly progressed over that time. Yet the change from mechanical controls and operator skills with digital electronics is not a matter of progress in a single technology. It marks the replacement of one technology by another.
It’s at this point that we enter into the second dimension of technological change. Mechanical controls and home economics classes did not gradually evolve into digital sewing machine controls; instead, one technology ousted another. Furthermore, both technologies do an equally good job of making a buttonhole. The factors driving the replacement of one by the other are external to the technologies themselves.
In the case of the sewing machines, as in so many similar technological transformations of the last sixty years or so, the replacement of one technology by another furthered a single process – the replacement of human skill by mechanical complexity. What drove this, in turn, was an economic equation closely parallelling the one that guided the rise of the global economy: the fact that for a certain historical period, all through the industrial world, energy was cheaper than human labor. Anything that could be done with a machine was therefore more profitable to do with a machine, and the only limitation to the replacement of human labor by fossil fuel-derived energy was the sophistication of the control systems needed to replace the knowledge base and nervous system of a skilled laborer. For most people today, that equation still defines progress. A more advanced technology, by this definition, is one that requires less human skill and effort to operate. The curve of progress thus seems to point to the sort of fully automated fantasy future that used to fill so many comic books and Saturday morning cartoons.
One of the major mental challenges of the near future, in turn, will consist of letting go of this image of the future and retooling our expectations to fit a very different reality. Behind the clever robots who populated the collective imagination, and the less clever but more tangible bits of household automation marketed so obsessively to the middle classes in recent decades, lies the replacement of human energy by mechanical energy derived mostly from fossil fuels. During the age of cheap abundant energy, this made economic sense, because the energy – and the machines needed to use it – were so much cheaper than the skilled labor they replaced. In the decades to come, as energy stops being cheap and abundant, that rule will no longer hold. What looked like the wave of the future, here as elsewhere, might well turn out to be a temporary adjustment to a short-term phenomenon.
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http://www.energybulletin.net/node/45837