Responsibilities of Competence - Understanding Understanding: Essays on Cybernetics and Cognition - page 193

or a diety to bestow favors on us in our search for new insights, and who
protects our society from evils from without as well as from within?
Astronomers and physicists are looked after by Urania; Demeter patron-
izes agriculture; and various Muses help the various arts and sciences. But
who helps Cybernetics?
One night when I was pondering this cosmic question I suddenly had an
apparition. Alas, it was not one of the charming goddesses who bless the
other arts and sciences. Clearly, that funny little creature sitting on my desk
must be a demon. After a while he started to talk. I was right. “I am
Maxwell's Demon”, he said. And then he disappeared.
When I regained my composure it was immediately clear to me that
nobody else but this respectable demon could be our patron, for Maxwell's
Demon is the paradigm for regulation .
As you remember, Maxwell's Demon regulates the flow of molecules
between two containers in a most unnatural way, namely, so that heat flows
from the cold container to the hotter, as opposed to the natural course of
events where without the demon's interference heat always flows from the
hot container to the colder.
I am sure you also remember how he proceeds: He guards a small aper-
ture between the two containers which he opens to let a molecule pass
whenever a fast one comes from the cool side or a slow one comes from
the hot side. Otherwise he keeps the aperture closed. Obviously, by this
maneuver he gets the cool container becoming cooler, and the hot container
getting hotter, thus apparently upsetting the Second Law of Thermody-
namics. Of course, we know by now that while he succeeds in obtaining this
perverse flow of heat, the Second Law remains untouched. This is because
of his need for a flashlight to determine the velocity of the upcoming
molecules. Were he at thermal equilibrium with one of the containers he
couldn't see a thing: he is part of a black body. Since he can do his antics
only as long as the battery of his flashlight lasts, we must include into the
system with an active demon not only the energy of the two containers, but
also that of the battery. The entropy gained by the battery's decay is not
completely compensated by the negentropy gained from the increased dis-
parity of the two containers.
The moral of this story is simply that while our demon cannot beat the
Second Law, he can, by his regulatory activity, retard the degradation of
the available energy, i.e., the growth of entropy, to an arbitrary slow rate.
This is indeed a very significant observation because it demonstrates the
paramount importance of regulatory mechanisms in living organisms. In
this context they can be seen as manifestations of Maxwell's Demon, retard-
ing continuously the degradation of the flow of energy, that is, retarding
the increase of entropy. In other words, as regulators living organisms are
“entropy retarders”.
Moreover, as I will show in a moment, Maxwell's Demon is not only
an entropy retarder and a paradigm for regulation, but he is also a func-