Martin, > > Hey Phil, > > Phil Henshaw wrote: > > Martin, > >> Hey Phil, > >> > >> If I understand you correctly, I think you're very right. The > >> information we have about the world is behavior and > >> appearances, and for > >> most interesting things the mechanism is completely hidden > >> from us. We > >> can observe inputs and outputs, but not the source code. > >> We can see > >> fuel go in and motion come out, but can't see the engine, > >> let alone > >> anything else. > > > > The trickiest piece is proving in a comprehendable and > > comprehensive > > way that anything has any actual inside structure, largely > > invisible > > from the outside. > > Well, I'd argue something slightly different. We need a > model of what's > going on inside, but that's not the same as recovering what's > actually > going on inside. In fact, a high level model may be more useful and > important than a low level one. For example, I can come up with the > concept of pressure, temperature and volume for a gas without > discovering molecules. I can do all kinds of useful and interesting > things knowing only about pressure, temperature and volume, like make > air conditioners and refrigerators, and have no idea whether gas is > continuous or made of molecules. > > As another example, there tends to be more traffic on the > roads during > morning and evening rush hour. This is an emergent phenomenon, and > would be hard to prove starting from a wiring diagram of the human > brain, plus whatever else about the environment you'd need to know. > > So I don't see the job so much as recovering the actual > structure that's > inside, but discovering regularities in the observables.
Well, that's what people have always done, of course, not bothered with the details that are hard or impossible to consider and made up something else that serves a current purpose. I call it 'approximation', and it's what science is mostly made of. It can be extremely useful. There are also times when overlooking the fuzzy or unavailable bits actually does matter and approximations don't help. One example would be a passive system, behaving in response to external controls, which is highly sensitive to initial conditions. Another is a natural system that isn't passive and has an independent internal behavior and design. That includes living things, and many other kinds of growth systems. There are several kinds of good proof. Where you have an active system with an interior, the loops of relationships it's built from are especially hard to see, inherently hidden as a consequence of only directly connecting to themselves, internally. They also tend to be too complicated, immeasurable and intermittent and original to figure out by indirect means. That also makes them 'approximately' non-existent if that's how you choose to interpret the hopelessness of your data on them. That a great many things highly important to us in the world are systems with active interior behavior and design is not yet something physics seems quite willing to admit, which makes it even more difficult to study them. Still, you can prove it by watching them build. Of course, we've also been told never to study individual things, since whatever they do that's interesting doesn't apply anyway. I'm coming at this from having focused on trying to understand what approximation leaves out. I found quite a lot, including that closely watching things that grow will usually expose classic individually unique developmental processes. There's only one place to say that's happening, i.e. inside. Approximation helped show me where to look, but only when I looked for what was left out and missing... There's obviously more to this, but the point is that the first step in learning about something deeply hidden is not building a model that looks familiar. It's figuring out how to watch the detailed workings of what you presently can't see. Phil > - Martin > > ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
