References and assumptions

[From Bruce Abbott (960924.1955 EST)]

Shannon Williams (960923.01:50) --

Rick Marken (960922.1940)

How would you model control without modeling the boundaries between
system and environment?

I agree that this boundary is needed. I do not agree that the boundary
always corresponds physically with an organism's skin. Surely we can
think of scenarios (driving a car, walking on crutches, using hearing aids,
placing a human brain in a robot body, etc.) where skin is not the system
boundary.

I don't think anyone has asserted that the boundary between system and
environment always corresponds physically with an organism's skin. In B:CP,
for example, Bill Powers explicitly treats lower systems in the HPCT
heirarchy as environment with respect to the higher systems, although the
lower systems are to be found entirely within the skin.

Regards,

Bruce