[From Bob Clark (930620.1010 pm EDT)]
Bill Powers (930615.0900 MDT);
In general, Bill, I agree with your outline of the operation of the
cells in a body. The only question in my mind is the extent to which
certain cells are directly involved in a feedback control system.
Certainly some are, but some are merely passive entities, "doing
their thing." This seems to be very much the case with kidney cells,
serving as passive filters subject to the "laws of osmosis" and the
like.
Over-all, they do not compose a "voluntary" control system -- nor set
of such systems. Indeed, the bulk of the physiological systems,
including those that function as control systems, seem to be
genetically determined.
And this brings up still another topic: which are "built in" and
which are "learned?"
Bill Powers (930616.0900 MDT)
After discussing in some detail some possible control relations among
cells, media, etc, addressing Oded Maler, you state:
I think that these apparent collective properties simply emerge from
the interaction of individual control systems, as measures like
entropy and pressure emerge from the interaction of individual
molecules. I think they live in a conceptual space, which exists
inside your head. You're creating an allegory or a metaphor, not a
literal model of how things work. You are reading something into
the world that actually comes from your own imagination. I say that
there is absolutely no evidence for collective perceptions,
collective reference signals, collective error signals, or
collective mechanisms for action.
Nicely said, Bill. I think you thought at first that I conceived
some kind of external, physically existing form of social control
systems. I think recent posts have now made our respective positions
clear -- that they exist exclusively within some portion, or portions,
of the hierarchy.
Bill Powers (930616.1230 MDT)
More of the same. Very well said. Yet I fear that I must point out
that producing "a stable phenomenon called pressure" in a gas is a
bit more complex than just the combinations of their properties and
interactions. We need energy, or temperature and gravity etc. The
general gas law has it complications.
We probably should develop a group of examples of physical phenomena
to illustrate and clarify some of these situations.
Regards, Bob Clark