On Constructing a Reality - Understanding Understanding: Essays on Cybernetics and Cognition - page 225

FIGURE 19.
Closure
By attending to all the neurophysiological pieces, we may have lost the per-
spective that sees an organism as a functioning whole. In Figure 18 I have
put these pieces together in their functional context. The black squares
labeled N represent bundles of neurons that synapse with neurons of other
bundles over the (synaptic) gaps indicated by the spaces between squares.
The sensory surface (SS) of the organism is to the left, its motor surface
(MS) to the right, and the neuropituitary (NP), the strongly innervated
master gland that regulates the entire endocrinal system, is the stippled
lower boundary of the array of squares. Nerve impulses traveling horizon-
tally (from left to right) ultimately act on the motor surface (MS) whose
changes (movements) are immediately sensed by the sensory surface (SS),
as suggested by the “external” pathway following the arrows. Impulses
traveling vertically (from top to bottom) stimulate the neuropituitary (NP),
whose activity release steroids into the synaptic gasp, as suggested by the
wiggly terminations of the lines following the arrow, and thus modify the
modus operandi of all synaptic junctures, hence the modus operandi of
the system as a whole. Note the double closure of the system that now
recursively operates not only on what it “sees,” but on its operators as well.
In order to make this twofold closure even more apparent I propose to wrap
the diagram of Figure 18 around its two axes of circular symmetry until the
artificial boundaries disappear and the torus (doughnut) in Figure 19 is
obtained. Here the “synaptic gap” between the motor and sensory surfaces
is the striated meridian in the front center, the neuropituitary the stippled
equator. This, I submit, is the functional organization of a living organism
in a (dough) nut shell.
The computations within this torus are subject to a nontrivial constraint,
and this is expressed in the postulate of cognitive homeostais:
The nervous system is organized (or organizes itself) so that it computes a stable
reality.
This postulate stipulates “autonomy,” that is, “self-regulation,” for every
living organism. Since the semantic structure of nouns with the prefix
self- becomes more transparent when this prefix is replaced by the noun,