A MPLI FY IN G R EG U LA TI ON
A third method for getting a regulator made is to assemble it in
Hardware, as a mechanic makes a water bath. Again selection is
Necessary: components have to be selected (distinguished) from
Other possible objects, and the mode of assembling and coupling
Has to be selected from the other, incorrect, modes. The quantity
Of selection used can be measured; and any dispute about the
Measurement can be resolved by the method of S.13/11 (final par-
Agraph).
It follows from S.13/18 that if the final regulator can be arrived
At by stages (the whole selection occurring in stages) the possibil-
Ity exists that the provision of a small regulator at the first stage
May lead to the final establishment of a much bigger regulator (i.e.
One of larger capacity) so that the process shows amplification.
This is the sense in which “amplifying” regulation is to be
Understood. The law of Requisite Variety, like the law of Conser-
Vation of Energy, absolutely prohibits any direct and simple mag-
Nification but it does not prohibit supplementation.
Let us consider some examples which will actually show
Such amplification of regulation.
Suppose the disturbances are fluctuations in the mains’ voltage,
Which come to an apparatus owned by Q at the rate of hundreds a
Second, and threaten to disturb it. Assume that the variety per sec-
Ond provided by these disturbances far exceeds his capacity as a
Channel, so it is impossible for him to regulate against them by
Direct personal action. However, he has available a manufac-
Turer’s catalogue, which shows three items:
Television set,
Mains stabiliser,
Frequency changer.
Assume that it is within his capacity for him to make a suitable
Selection of one from three; if now he performs the appropriate
Selection, the end result will be that the brains’ supply to his appa-
Ratus will become stabilised. Thus his three possible primary
Selections can be put into correspondence with three outcomes,
One of which is “mains’ voltage stabilised”.
The latter regulation (over, say, a year) involves far more selec-
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Tion than of one from three; so over the whole transaction an
Undoubted amplification has occurred.
In this example the supplementation is so obvious, and his
Dependence on the manufacturer’s power as a designer so blatant,
That the reader may be tempted to dismiss this “amplification” as
268
Not worth serious consideration. (It is not, however, more blatant
Than the crane-driver’s dependence on a suitable power supply.)
This case, however, is only somewhat extreme (having been
Selected to show one end of the scale). Other cases lie further
Along the scale, and are of more general interest. The principle,
However, remains unaltered.
Next consider the case in which Q wants a water bath to be
Restored to a certain temperature; restorations will be required 100
Times in each day and over a whole year. This means that on
Occasions the temperature must be corrected by a raising
Or a lowering— a one-bit selection, say. The whole Grand Distur-
Bance (S.13/8) thus has variety of 236S00 possibilities. Q proba-
Bly could transmit this in the year, but finds it inconvenient. If
Then his resources are such that he can make a thermostat at a cost
Of, say, 1000 bits, then by using the fact that the Grand Distur-
Bance is repetitive (S.13/9), the act of selecting appropriately from
Bits has as consequence the correct selection from 36,500
Bits. So an amplification of about x 36 (if measured on the loga-
Rithmic scale) has occurred.
This second example is more ordinary than the first. The fact
That its method is widely used in practice shows whether or not the
Practical man thinks it worth while.
There is, of course, not necessarily any amplification; and the
Practical man, before he builds a machine to do a job, always
Makes at least an intuitive assessment of the balance:
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Cost incurred by doing itCost (in some sense) of making
Himself.the machine which will do the
Job.
What this chapter deals with are the actual quantities involved,
When our interest is centred on the amount of communication and
Selection that is required.
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