🚀 go-pugleaf

[From Bruce Gregory (990422.1533 EDT)]

Mary Powers 9904.22

> It is rather insulting to claim that all PCT is based on chapter 1 of
> control system texts.

Since I made that statement, I want to be clear that I was speaking from
a possible control engineer's point of view. The basics of PCT can be
demonstrated in a very simple control loop. This makes PCT look almost
trivial _if_ you think you understand how a thermostat works. As you
point out in reference to Three Mile Island, not all engineers
understand as much as they think they do. Taking the system's point of
view is obviously a _major_ change in viewpoint that many people are
unable to make. I suspect the reason is that they do not realize just
how big a step it is.

> As for why choose PCT over traditional engineering:  the
> thing that is being
> sneered at here, PCT's "simplicity", is its virtue.

I don't know who was sneering, but it wasn't me. It's simplicity is
without question its strength.

> Can you imagine a
> bacterium packing the equipment necessary for model-based
> control?  To be
> able to describe the performance of bacteria, and increasing
> complex ones
> such as humans, by the proliferation of the same simple
> element into huge
> hierarchies, is parsimonious and elegant, and takes evolution
> into account
> as well as things-as-they-are.

No question about it. It's elegance is more than impressive, it is
compelling.


Bruce Gregory