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3

Regulation and Control

The “diagram of immediate effects”, introduced by Ashby (1956), is an excellent

way of formalizing functional relationships. An example is the regulatory network

in Fig. 3.1.

Problem. Construct a concrete example of a hierarchical control system.

Problem. Construct diagrams of immediate effects for familiar biochemical pro-

cesses.

3.4

Adaptation

Adaptation is perhaps the most characteristic feature of life. The process of adapta-

tion has been formalized by Sommerhoff (1950). The “disturbance” (cf. Sect. 3.2)

presented at epocht 0t0 is denoted the coenetic variableupper D Subscript t 0Dt0, the “hardware” (approxi-

mately equivalent to T in Sect. 3.2) is the environmental circumstance upper E Subscript t 1Et1, the “reg-

ulator” (approximately equivalent to R in Sect. 3.2) is the response upper R Subscript t 1Rt1 directively

correlated with upper E Subscript t 1Et1, both upper RR and upper EE taking place at a particular subsequent epoch t 1t1,

and the “essential variables” (cf. Sect. 3.2) constitute the focal condition or goal upper GG

of the organism that reaches its consummation at the still later epoch t 2t2.

The usual notion of adaptedness, as applied to biological systems, implies no more

than appropriateness. In other words, the statement that an (organic) response upper RR is

adapted to the environmental circumstances upper EE from the viewpoint of some future

state of affairs upper GG (toward the realization of which it is considered to be directed)

implies that the response is appropriate and, hence, also effective in bringing about the

actual (or at least the probable) occurrence ofupper GG. However, although this “definition”

of adaptedness is easy to state, it is not only trivial in meaning but is also fraught

with difficulties. For one thing, it does not allow us to prefer the statement “the

fish is adapted to the aquarium in which it survives” to “the aquarium is adapted

to the fish it contains”. Another difficulty is presented by that numerous category

of accidental activity. Many accidental occurrences (including random mutations of

DNA) are highly effective in bringing about a certain response but could hardly be

called adapted; in the case of a random mutation, for example, adaptation could be

said to have occurred only after it had become fixed in the population due to the

advantages it conferred on the organism.

In Sommerhoff’s formulation (see also Sommerhoff 1990), adaptation (i.e., the

statement that upper R Subscript t 1Rt1 is adapted to upper E Subscript t 1Et1 with respect to upper G Subscript t 2Gt2) means that if a changed

disturbance upper D Subscript t 0Dt0 caused the occurrence of an alternative member of the set of upper EEs

(environmental circumstances), it would also have caused the occurrence of an alter-

native member of the set ofupper RRs (appropriate responses) such that the goalupper G Subscript t 2Gt2 would

still have been achieved. In other words, the responseupper RR is not only appropriate given

the actual environmental circumstance upper EE but would also have been appropriate had

the initial disturbance upper DD been different. It should be emphasized that upper EE and upper RR are

epistemically independent variables (if they were dependent, then achievement of

the goal would merely be a manifestation of physical stability). The disturbance upper DD