Berlinski continued: a rule against deferred success .... But the rule is widely violated, the violations so frequent as to amount to a formal fallacy.
The Artificer of Design
RANDOM MUTATIONS are the great creative demiurge of evolution, throwing up possibilities and bathing life in the bright light of chance. Each living creature is not only what it is but what it might be. What, then, acts to make the possible palpable?
The theory of evolution is a materialistic theory. Various deities need not apply. Any form of mind is out. Yet a force is needed, something adequate to the manifest complexity of the biological world, and something that in the largest arena of all might substitute for the acts of design, anticipation, and memory that are obvious features of such day-to-day activities as fashioning a sentence or a sonnet.
This need is met in evolutionary theory by natural selection, the filter but not the source of change. "It may be said," Darwin wrote,
that natural selection is daily and hourly scrutinizing, throughout the world, every variation, even the slightest;
rejecting that which is bad, preserving and adding up all that is good: silently and insensibly working, whenever and
wherever opportunity offers, as the improvement of each organic being in relation to its organic and inorganic
conditions of life.
Natural selection emerges from these reflections as a strange force-like concept. It is strange because it is unconnected to any notion of force in physics, and it is force-like because natural selection does something, it has an effect and so unctions as a kind of cause.(4)
[(4) Murray Eden is, as usual, perceptive: "It is as if," he writes some pre-Newtonian cosmologist had proposed a theory of planetary motion which supposed that a natural force of unknown origin held the planets in their courses. The supposition is right enough and the idea of a force between two celestial bodies is a very useful one, but it is hardly a theory."]
Creatures, habits, organ systems, body plans, organs, and tissues are shaped by natural selection. Population geneticists write of selection forces, selection pressures, and coefficients of natural selection; biologists say that natural selection sculpts, shapes, coordinates, transforms, directs, controls, changes, and transfigures living creatures.
It is natural selection, Richard Dawkins believes, that is the artificer of design, a cunning force that mocks human ingenuity even as it mimics it:
Charles Darwin showed how it is possible for blind physical forces to mimic the effects of conscious design, and, by
operating as a cumulative filter of chance variations, to lead eventually to organized and adaptive complexity, to
mosquitoes and mammoths, to humans and therefore, indirectly, to books and computers.
In affirming what Darwin showed, these words suggest that Darwin demonstrated the power of natural selection in some formal sense, settling the issue once and for all. But that is simply not true. When Darwin wrote, the mechanism of evolution that he proposed had only life itself to commend it. But to refer to the power of natural selection by appealing to the course of evolution is a little like confirming a story in the New York Times by reading it twice. The theory of evolution is, after all, a general theory of change; if natural selection can sift the debris of chance to fashion an elephant's trunk, should it not be able to work elsewhere- amid computer programs and algorithms, words and sentences? Skeptics require a demonstration of natural selection's cunning, one that does not involve the very phenomenon it is meant to explain.
No sooner said than done. An extensive literature is now devoted to what is optimistically called artificial life. These are schemes in which a variety of programs generate amusing computer objects and by a process said to be similar to evolution show that they are capable of growth and decay and even a phosphorescent simulacrum of death. An algorithm called "Face Prints," for example, has been designed to enable crime victims to identify their attackers. The algorithm runs through hundreds of facial combinations (long hair, short hair, big nose, wide chin, moles, warts, wens, wrinkles) until the indignant victim spots the resemblance between the long-haired, big-nosed, widechinned portrait of the perpetrator and the perpetrator himself.
It is the presence of the human victim in this scenario that should give pause. What is he doing there, complaining loudly amid those otherwise blind forces? A mechanism that requires a discerning human agent cannot be Darwinian. The Darwinian mechanism neither anticipates nor remembers. It gives no directions and makes no choices. What is unacceptable in evolutionary theory, what is strictly forbidden, is the appearance of a force with the power to survey time, a force that conserves a point or a property because it will be useful. Such a force is no longer Darwinian. How would a blind force know such a thing? And by what means could future usefulness be transmitted to the present?
If life is, as evolutionary biologists so often say, a matter merely of blind thrusting and throbbing, any definition of natural selection must plainly meet what I have elsewhere called a rule against deferred success.(5)
[(5) _Black Mischief: Language, Life, Logic & Luck_ (1986).]
It is a rule that cannot be violated with impunity; if evolutionary theory is to retain its intellectual integrity, it cannot be violated at all.
But the rule is widely violated, the violations so frequent as to amount to a formal fallacy.
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