Jack Park wrote: From my, possibly naive, Rosennean view, it seems to me that the entailment structures map to each other.
** *Once again, it matters what you want "the model" to do. If you want a rough commutativity between the real airplane and the model such that thrust plus wingshape, plus ? equals, whatever... then you have a modeling relation. I was thinking about the kinds of things like pilot inside airplane, small moving parts in engine and flammable fueltanks on board, passengers and luggage and the exigencies of how to balance all that such that you can still become airborne and remain stable, the density of atmosphere at whatever altitude the plane is supposed to fly, how to compensate for thin atmosphere inside the cabin, what safeties are in place for various weather conditions, etc... none of which are engineered into the toy airplane. It's different, contextually. It models some aspects of airplane flight, but simulates others. How's that?!*
** *Judith*
----- Original Message ----- *From:* Jack Park <mailto:***> *To:* *** <mailto:***> *Sent:* Friday, December 31, 2004 1:28 PM *Subject:* Re: [ROSEN] simulation vs. mimesis
Model airplanes of the radio-control type. I own those. Judith said: <quote> The causal entailments of an airplane (which constitute the "guts" of an airplane's functionality) are not present in the model... </quote>
Say what?
Let me enumerate my view of the functionalities of an airplane, be it a model or one you climb in and fly (I built those too). They are: overcoming drag forces overcoming gravitational forces
Now, in my, possibly naive, Rosennean view, drag forces are entailed by a body moving through a fluid, such as air; gravitational forces are entailed by the mass that is the airplane, whether model or "real".
Drag entails thrust. Thrust entails a thrust-producing device, be it a propeller-with-engine, or jet or rocket, (or rubberband slingshot, as in some models). Lift entails lifting devices, typically called "wings", which are known to have airfoil shapes which entail pressure differences between the upper and lower surfaces, those pressure differences entailed by the motion of air over the surface, whether that motion is the air moving over the surface or the surface moving within a mass of air. It's all relative, I suppose.
So, building a model airplane (mine are mostly gliders, some with gas or electric moters to launch them to appropriate altitudes), I install wings, tail feathers, and motors, plus electronics and servos for controls. That all adds weight, so, again, gravity is entailed, and lift is required. Moving that mass around in air entails drag, requiring thrust. Some thrust can be provided by a propulsive force, and some can come out of a vector analysis of the forces entailed by a wing moving through an air mass while descending (gliding).
From my, possibly naive, Rosennean view, it seems to me that the entailment structures map to each other. The primary differences being those related to scale effects, known as Reynolds number effects; that is to say, the lift-to-drag polars of a model will not be anything near as "good" as they are with a "real" airplane.
So, how can you say <quote> However, even there I would suggest that the reasons why the toy airplane is able to fly are mostly not the same as the reasons the real airplane is able to fly. The entailment structures don't commute very well. </quote>
Inquiring minds want to know... Jack
Judith Rosen wrote:
> *That's OK, Howard, that's what makes horseraces.* > ** > *Sometimes it's important to "play devil's advocate" and show how > aspects of Yin are embodied/entailed-by Yang, and vice versa. Otherwise, > we might forget and become hidebound-- not a good thing to become.* > ** > *Incidentally... I would argue that the causal entailments of an > airplane (which constitute "the guts" of an airplane's functionality) > are not present in the model. However, the model I have in my mind's eye > is a little plastic one like the ones that my brother used to build from > a kit, with modeling glue, and it only "looked like" an airplane. It was > perfectly hollow and if you tried to make it fly, it tended to plummet > and break into a zillion pieces. You may be imagining a model airplane > that is a remote-controlled flying toy airplane...* > ** > *However, even there I would suggest that the reasons why the toy > airplane is able to fly are mostly not the same as the reasons the real > airplane is able to fly. The entailment structures don't commute very > well. So the flying toy may be a useful model for demonstrating what > happens to a real airplane when interacting with a downdraft, perhaps, > or some other application where the missing entailment structures don't > impact the outcome... * > ** > *We need to remember, though, that all of these airplane and model > examples are still dealing with "machines"... simple systems. When we > are dealing with new territory, like relational models of complex or > complex/living systems, it is wise never to make that assumption (that > the missing entailment structures won't impact the outcome).... and I > would side with Tim, in that case, myself. * > ** > *(But my reasons for doing so are different!)* > **** > *Judith (the-devil-made-me-do-it) Rosen* > /PS: Happy last day of the year, everybody!/ > > ----- Original Message ----- > *From:* Howard Pattee <mailto:***> > *To:* *** <mailto:***> <mailto:***> > *Sent:* Friday, December 31, 2004 2:43 PM > *Subject:* Re: [ROSEN] simulation vs. mimesis > > Judith, > > I have to side with Tim. A model airplane has the basic causal > entailments > of an airplane. It flies. A simulator doesn't. This is an important > distinction. > > Howard