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(pp. 3087-8). Six weeks later Ashby recorded that “DAMS has reached the
size of ten valves, and,” he added, “has proved exceedingly difficult to under-
stand.” He continued (14 March 1951, pp. 3148-51),
But while casting around for some way of grasping it I came across a new idea.
Why not make the developent of DAMS follow in the footsteps marked out by
evolution, by making its variations struggle for existence? We measure in some
way its chance of “survival,” and judge the values of all proposed developments
by their effects on this chance. We know what “survival” means in the homeo-
stat: we must apply the same concept to DAMS. . . .
The method deserves some comment. First notice that it totally abandons
any pretence to “understand” the assembly in the “blue-print” sense. When
the system becomes highly developed the constructor will be quite unable to
give a simple and coherent account of why it does as it does. . . . Obviously in
these circumstances the words “understand” and “explain” have to receive new
meanings.
This rejection of the “blue-print” attitude corresponds to the rejection of
the “blue-print” method in the machine itself. One is almost tempted to dog-
matise that the Darwinian machine is to be developed only by the Darwinian
process! (there may be more in this apothegm than a jest). After all, every
new
development in science needs its own
new
techniques. Nearly always, the new
technique seems insufficient or hap-hazard or plain crazy to those accustomed
to the old techniques.
If I can, by this method, develop a machine that imitates advanced brain
activities without my being able to say how the activities have arisen, I shall be
like the African explorer who, having heard of Lake Chad, and having sought
it over many months, stood at last with it at his feet and yet, having long since
lost his bearings, could not say for the life of him where in Africa Lake Chad
was to be found.
This is a remarkable passage of ontological reflection, which gets us back
to the cybernetic discovery of complexity from a new angle. Like Walter's
tortoise, the homeostat had been designed in detail from the ground up—the
blueprint attitude—and this approach had been sufficient, inasmuch as the
two machines did simulate performances of the adaptive brain. My argument
was, however, that when constructed, they remained to a degree imperme-
able Black Boxes, displaying emergent properties not designed into them (the
tortoise), or otherwise opaque to analysis (the multihomeostat setup). But it
was only with DAMS that Ashby had to confront this discovery of complexity
