Berlinski continued:
Sheer Dumb Luck
CHANCE ALONE," the Nobel Prize-winning chemist Jacques Monod once wrote, "is at the source of every innovation, of all creation in the biosphere. Pure chance, absolutely free but blind, is at the very root of the stupendous edifice of creation."
The sentiment expressed by these words has come to vex evolutionary biologists. "This belief," Richard Dawkins writes, "that Darwinian evolution is 'random,' is not merely false. It is the exact opposite of the truth." But Monod is right and Dawkins wrong. Chance lies at the beating heart of evolutionary theory, just as it lies at the beating heart of thermodynamics.
It is the second law of thermodynamics that holds dominion over the temporal organization of the universe, and what the law has to say we find verified by ordinary experience at every turn. Things fall apart. Energy, like talent, tends to squander itself. Liquids go from hot to lukewarm. And so does love. Disorder and despair overwhelm the human enterprise, filling our rooms and our lives with clutter. Decay is unyielding. Things go from bad to worse. And overall, they go only from bad to worse.
These grim certainties the second law abbreviates in the solemn and awful declaration that the entropy of the universe is tending toward a maximum. The final state in which entropy is maximized is simply more likely than any other state. The disintegration of my face reflects nothing more compelling than the odds. Sheer dumb luck.
But if things fall apart, they also come together. Life appears to offer at least a temporary rebuke to the second law of thermodynamics. Although biologists are unanimous in arguing that evolution has no goal, fixed from the first, it remains true nonetheless that living creatures have organized themselves into ever more elaborate and flexible structures. If their complexity is increasing, the entropy that surrounds them is decreasing. Whatever the universe-as-a-whole may be doing -- time fusing incomprehensibly with space, the great stars exploding indignantly -- biologically things have gone from bad to better, the show organized, or so it would seem, as a counterexample to the prevailing winds of fate.
How so? The question has historically been the pivot on which the assumption of religious belief has turned. How so? "God said: 'Let the waters swarm with swarms of living creatures, and let fowl fly above the earth in the open firmament of heaven."' That is how so. And who on the basis of experience would be inclined to disagree? The structures of life are complex, and complex structures get made in this, the purely human world, only by a process of deliberate design. An act of intelligence is required to bring even a thimble into being; why should the artifacts of life be different?
Darwin's theory of evolution rejects this counsel of experience and intuition. Instead, the theory forges, at least in spirit, a perverse connection with the second law itself, arguing that precisely the same force that explains one turn of the cosmic wheel explains another: sheer dumb luck.
If the universe is for reasons of sheer dumb luck committed ultimately to a state of cosmic listlessness, it is also by sheer dumb luck that life first emerged on earth, the chemicals in the pre-biotic seas or soup illuminated and then invigorated by a fateful flash of lightning. It is again by sheer dumb luck that the first self-reproducing systems were created. The dense and ropy chains of RNA -- they were created by sheer dumb luck, and sheer dumb luck drove the primitive chemicals of life to form a living cell. It is sheer dumb luck that alters the genetic message so that, from infernal nonsense, meaning for a moment emerges; and sheer dumb luck again that endows life with its opportunities, the space of possibilities over which natural selection plays, sheer dumb luck creating the mammalian eye and the marsupial pouch, sheer dumb luck again endowing the elephant's sensitive nose with nerves and the orchid's translucent petal with blush.
Amazing. Sheer dumb luck.
Life, Complex Life
PHYSICISTS ARE persuaded that things are in the end simple; biologists that they are not. A good deal depends on where one looks. Wherever the biologist looks, there is complexity beyond complexity, the entanglement of things ramifying downward from the organism to the cell. In a superbly elaborated figure, the Australian biologist Michael Denton compares a single cell to an immense automated factory, one the size of a large city:
On the surface of the cell we would see millions of openings, like the portholes of a vast space ship, opening
and closing to allow a continual stream of materials to flow in and out. If we were to enter one of these openings we
would find ourselves in a world of supreme technology and bewildering complexity. We would see endless highly
organized corridors and conduits branching in every direction away from the perimeter of the cell, some leading
to the central memory bank in the nucleus and others to assembly plants and processing units. The nucleus itself
would be a vast spherical chamber more than a kilometer in diameter, resembling a geodesic dome inside of which we
would see, all neatly stacked together in ordered arrays, the miles of coiled chains of the DNA molecule.... We would
notice that the simplest of the functional components of the cell, the protein molecules, were, astonishingly, complex
pieces of molecular machinery....Yet the life of the cell depends on the integrated activities of thousands, certainly
tens, and probably hundreds of thousands of different protein molecules.
And whatever the complexity of the cell, it is insignificant in comparison with the mammalian nervous system; and beyond that, far impossibly ahead, there is the human mind, an instrument like no other in the biological world, conscious, flexible, penetrating, inscrutable, and profound.
It is here that the door of doubt begins to swing. Chance and complexity are countervailing forces; they work at cross-purposes. This circumstance the English theologian William Paley (1743-1805) made the gravamen of his well-known argument from design:
Nor would any man in his senses think the existence of the watch, with its various machinery, accounted for, by being told that it was one out of possible combinations of material forms; that whatever he had found in the place where he found the watch, must have contained some internal configuration or other, and that this configuration might be the structure now exhibited, viz., of the works of a watch, as well as a different structure. It is worth remarking, it is simply a fact, that this courtly and old-fashioned argument is entirely compelling. We never attribute the existence of a complex artifact to chance. And for obvious reasons: complex objects are useful islands, isolated amid an archipelago of useless possibilities. Of the thousands of ways in which a watch might be assembled from its constituents, only one is liable to work. It is unreasonable to attribute the existence of a watch to chance, if only because it is unlikely. An artifact is the overflow in matter of the mental motions of intention, deliberate design, planning, and coordination. The inferential spool runs backward, and it runs irresistibly from a complex object to the contrived, the artificial, circumstances that brought it into being.
Paley allowed the conclusion of his argument to drift from man-made to biological artifacts, a human eye or kidney falling under the same classification as a watch. "Every indication of contrivance," he wrote, "every manifestation of design, exists in the works of nature; with the difference, on the side of nature, of being greater or more, and that in a degree which exceeds all computation.
In this drifting, Darwinists see dangerous signs of a non sequitur. There is a tight connection, they acknowledge, between what a watch is and how it is made; but the connection unravels at the human eye -- or any other organ, disposition, body plan, or strategy -- if only because another and a simpler explanation is available. Among living creatures, say Darwinists, the design persists even as the designer disappears.
"Paley's argument," Dawkins writes, "is made with passionate sincerity and is informed by the best biological scholarship of his day, but it is wrong, gloriously and utterly wrong."
The enormous confidence this quotation expresses must be juxtaposed against the weight of intuition it displaces. It is true that intuition is often wrong-quantum theory is intuition's graveyard. But quantum theory is remote from experience; our intuitions in biology lie closer to the bone. We are ourselves such stuff as genes are made on, and while this does not establish that our assessments of time and chance must be correct, it does suggest that they may be pertinent. |
