What we don’t or can’t comprehend might be called magic. By this measure, most of the universe is—and always will be—magic. That’s okay. The faith of a materialist monist is that the universe “knows” what it’s doing, and expresses itself in astoundingly diverse ways using an elegantly small number of particle and interaction types: more than compensating via breathtaking emergent complexity. We needn’t grok it all for everything to still work splendidly.

Often, the universe—or an element within it—appears to our naïve eyes to express intent. Organisms seem purposeful. Some aspects of our existence appear to be tuned just-so; self-referential; tautological; teleological. A star perches right on the edge of fusion, sipping its fuel as slowly as it effectively can. Earth finds thermal balance because a 1% departure from normal (absolute) temperature results in a 4% change in the rate of heat loss in the opposite direction (hotter amps up cooling; cooler curtails it substantially). The cell membrane of an egg yolk—or an egg shell, for that matter—is as thick as it needs to be to maintain integrity, but no thicker. Bones are as big as they need to be, and no bigger. Plants and animals tend to exercise sound judgment on the when, where, and how of the actions they take. It’s a world full of Goldilocks scenarios.

The result really is amazing and can easily seem magical. In such cases, ask whether the circular just-so nature might be attributable to feedback, which is also loop-like, and holds more power than is apparent. This post attempts to teach a bit of electronics before returning to how feedback performs effective magic in the real world. While it might seem a diversion, a grasp of feedback in the (much simpler/tidier) electronic domain can bolster appreciation of its power (magic) in the wider world.

Views: 241