[From Bruce Gregory 9981129.1250 EDT)]
Rick Marken (981129.0930)
It wasn't clear what everything after the "if" meant. But I don't see
how even a generous interpretation of its meaning can save it. It is
simply not true that "all [outputs] will _eventually_ work if you let
the direction of error change determine the next output".
Would you be any happier (a lot to ask I admit) if I told you that the "if"
means you can start out any way you like as long as you let the direction of
error change determine the next output?
> Most of E. coli's outputs are "wrong". Does this prevent it from
> achieving its "goals"?No. What would prevent E. coli from achieving its goals would be if
_all_ of its outputs were wrong every time -- which is a real (though
low probability) possibility.
We certainly agree on the lowness of the probability. Perhaps I should quit
on this point.
> What is the nature of a "disturbance" as far as E. coli is concerned?
Changes in perceived concentration that are _not_ caused by E. coli's
own
actions. The actual shape of the concentration gradient is one such
disturbance.
Well, I have learned something after all. The world is a disturbance as far
as E. coli is concerned. This puts a new slant on the meaning of disturbance
that I had not appreciated before. The world is a disturbance for any
intentional system. Interesting way to think of the world, sort of Buddhist
is flavor. All suffering comes from allowing the world to disturb you. If
you simply match your reference levels to your perceptions, you will never
be disturbed. Nice point.
> Is its organization any different if "disturbances" are present?
No. But I don't see what this has to do with my basic point, which is
that there is right and wrong in control; only the outputs that oppose
the net effects of disturbances to a controlled variable are "right";
all other outputs are "wrong".
With my new found understanding of "disturbance," I can hardly disagree.
Bruce Gregory