Everyone has heard of Moore's law, but there is no obvious reason for its truth. Moore formulated a hypothesis based on inductive reasoning, and it has--amazingly--continued to hold for 40 years. You may not have heard of Kryder's law of disk density, or the others above, but there are many examples of exponential change in the world of technology. Kevin Kelly, Senior Maverick at Wired magazine, is right to draw attention to this strange phenomenon. What is it about technology that lends itself to exponential growth?
One way to answer is to take the side of technological determinism: there's just something about technologies like chip manufacturing. Perhaps it takes a certain amount of time to develop the knowledge to create a certain chip density, and then it takes that same amount of time to double it. This is a reasonable answer, since the development life cycles of projects are typically fixed (at, say, 18 months to two years) and that halving or doubling something every life cycle is a common goal.
Moore's own answer was that his "law" was simply a target at which people could aim. There's nothing inherent about chip manufacturing that lends itself to exponential growth. The notion that chip density should grow exponentially is a human construct.
Neither of these answers is particularly appealing to me. I don't really know what to think. Kelly notes that what looks like a smooth line is actually the waxing and waning of multiple technologies. For example, tape density is not a single technology but is composed of at least three different ones. In other words, each paradigm allows for exponential improvement upon its predecessors. This makes the story of exponential growth contingent upon the invention of new paradigms, but it is surely worth pondering why we have been able to do this over and over again.
