by Stuart Kauffman
Oxford University Press, 1995.
Suggested price: $25

Reviewed by William Tucker

Stuart Kauffman, one of the pioneers of "complexity theory" at the Santa Fe Institute, puts forth his full-dress argument for a revision of Darwinian theory. Kauffman argues that the emergence of "spontaneous order" in the universe makes the emergence of evolutionary life on earth much more likely than previously supposed. It is upon self-replicating feedback loops formed among large organic molecules, and not the individual molecules themselves, that natural selection has been acting.

Each cell of an organism, for example, contains the blueprint to make every protein and express itself as every other cell in the organism. Yet each cell expresses itself in only one way. Why is this so?

The answer was that the cell somehow "knows" or "is directed" to limit its expression. But how does it know? And who or what directs it?

The unconscious assumption of many biologists had been that there must be some "master" gene that directs the process. Knowing a bit about the emerging discipline of computer science, however, Kauffman opted to approach the problem from a systems angle. Instead of being directed from some central command post, perhaps the actions of each gene were governed purely by their interactions with other genes.

He began by picturing each in an "on" or "off" position at any moment. The entire complex of genes can then arrange itself into any number of patterns, like light bulbs on a flashing electric sign. What rules could possibly be devised that might produce a series of repeating or recognizable patterns?

The numbers quickly become overwhelming. With only 200 individual genes, the number of patterns in which an organism can arrange itself is 10⁶⁰. (The human genome contains about 100,000 genes.) If each configuration blinked for only a millionth of a second, it would take a billion times the 15-billion-year history of the universe before any pattern would have to repeat itself. How could an orderly sequence of events possibly emerge from such chaos?

Undaunted, Kauffman kept going. Borrowing time on a neighboring computer, he set up a system of 200 "digital organisms," each with an on-off position. What would happen, he asked, if the position of each unit at any moment were governed by the on-off position of one, two, three, or any number of units at the previous moment? Writing a simple program, Kauffman began to experiment.

When each unit was controlled by one other unit, nothing emerged. The system remained random and chaotic, never repeating itself. When each unit was governed by three or more units, the system quickly froze in one fixed position. Nothing ever changed.

But when the position of each unit was controlled by the previous position of two other units, something sublime happened. The blinking patterns quickly fell into a small number of sequences that began endlessly repeating themselves. For any given sequence, the system would blink through about 10 to 20 different positions, then loop back to its original position and repeat the sequence again. Kauffman called these patterns basins of attraction.

Most remarkably, the number of patterns into which the system fell was stunningly small. For a system of 200 units, with 10⁶⁰ possible configurations, the number of basins of attraction was 14!

"This result astonished me at the time," writes Kauffman. "It still astonishes me."

Working with various scenarios, Kauffman worked out a general rule. Under this rule, the number of basins of attraction into which a system can fall - each unit governed by the previous position of two other units - is roughly the square root of the number of units in the system. Then, in one of those exciting discoveries that has marked the emergence of complexity theory, Kauffman found that geneticists had already worked out a general rule of thumb concerning the relationship of genes and their expression in an organism. The number of cell types in an organism is roughly the square root of the number of its genes.

Kauffman's discovery became one of the first inklings of spontaneous or emergent order. The basic concept is that the universe arranges itself into organized systems much more easily than has been previously suspected. All this may be nothing more than a law of very large numbers that only became accessible with the emergence of computers. But Kauffman has discovered a principle that shakes the model of Darwinian evolution to its very roots.

As Kauffman points out, the reigning paradigm of evolution in recent years has been Jacques Monad's model of chance and necessity. According to this interpretation, the evolution of life on earth has been an astonishing exception to the general disorder and entropy of the universe. In his book, Chance and Necessity, Monad describes at one point a confrontation between a biologist and a Catholic priest. The priest says he does not believe in evolution because "life is a miracle." The biologist replies, "When you understand the unlikelihood of life on earth, you realize that our theory describes the true miracle."

Kauffman now argues that both these explanations are untrue. Evolution, far from being a miracle or a series of improbable chance mutations, has been much more a part of the natural unfolding of the universe. To be sure, it may take nearly a billion years for life to evolve on a planet, but given the tendency of self-organizing systems to emerge in nature, it is still not all that unlikely. Moreover, once a level of self-organization has been attained, that level serves as a stepping stone to other levels of organization. Organisms with undifferentiated cells existed on earth for 3 billion years without much change. But when cells began specializing, life suddenly exploded into a riot of new multi-celled organisms - the Cambrian Explosion. As Kauffman says, "If the universe is running down because of the second law [of thermodynamics], the evidence outside my window is sparse. . . It is not entropy but the extraordinary surge toward order that strikes me."

One of the most effective arguments of the creationists against evolution has been that there simply hasn't been enough time for the whole process to occur. Robert Shapiro, in his book, Origins: A Skeptic's Guide to the Creation of Life, calculates that there could have been 10⁵¹ attempts to create life by chance since the dawn of the earth. But the chances of assembling a single bacterial enzyme by chance are only 1 in 10²⁰. With 200 enzymes needed to create a functioning organism, the odds of primitive life emerging are only
1 in 10^40,000. (There are only 10⁶⁰ hydrogen molecules in the universe.) The probability that life could have emerged through chance assembly of organic molecules is ridiculously small.

Yet Kauffman suggests that it is not individual proteins that are being screened by nature, but the interactions among proteins and genes themselves. When it is only the "basins of attraction" among interacting parts that must be screened, the possibilities for natural selection become entirely feasible. Darwin is not wrong, Kauffman concludes, but his theory needs revising. Darwinian selection has been the winnowing mechanism of evolution, but it is not the chance creation of individual molecules on which it has been acting:

Most biologists, inheritors of the Darwinian tradition, suppose that the order of ontogeny is due to the grinding away of a molecular Rube Goldberg machine, slapped together piece by piece by evolution. I present a countering thesis: Most of the beautiful order seen in ontogeny is spontaneous, a natural expression of the stunning self-organization that abounds in very complex regulatory networks. We appear to have been profoundly wrong. . . Order, vast and generative, not fought for against the entropic tides but freely available, undergirds all subsequent biological evolution.

"If all this is true," he continues, "what a revision of the Darwinian worldview will lie before us! Not we the accidental, but we the expected." The evolution of life has not been the freak accident, but part of the natural unfolding of the universe.

Nor does Kauffman shrink from the implications of this theory. "Not only are we at home in the universe," he concludes, "but we are far more likely to share it with as yet unknown companions." (All this was written well before the recent discoveries that may or may not have proved that there was once life on Mars.)

Kauffman's theories have implications for the social sciences as well.

For the better part of this century, economists have argued over whether the free market or the planned economy is the best tool for economic progress. A significant school of thought in the twentieth century has argued that the free market produces only disorder and chaos and must be guided by political organization. The "planned economies" of much of the world have been the result of these theories.

Among the most prominent critics of planning have been the Austrian school of economics, founded in Vienna in the late nineteenth century. Ludwig Von Mises, the dean of the Austrians, wrote a book entitled Socialism in 1921 in which he predicted that the Soviet Union, then only four years old, would eventually collapse because the suppression of prices and exchange of information between producers and consumers were destroying the information needed to run an economy. No amount of central planning could overcome this information disaster. Groping for a phrase in 1945 to describe the workings of a free economy, Friedrich Von Hayek, Von Mises' pupil and winner of the Nobel Prize in 1973, came up with the term spontaneous order.

It appears the free marketeers have finally found in Kauffman their scientific patron. Although only marginally aware of the Austrian school, Kauffman has put mathematical flesh on their vaguely articulated concept of self-organization and spontaneous order. Kauffman even uses Adam Smith's famous metaphor of the "invisible hand" to describe how economies and ecosystems arrange themselves: "As if by an invisible hand, each adapting species acts according to its own selfish advantage, yet the entire system appears magically to evolve to a poised state where, on average, each does as best as can be expected."

The implication is clear. A free society that allows each individual to seek his or her own selfish ends (without deliberately trying to harm anyone else) will produce a state in which everyone's interest is optimized without any individual knowing in advance what that state might be. Says Kauffman: "Complexity offers fresh support for the idea that pluralistic democratic society, providing evidence that it is not merely a human creation but part of the natural order of things. . . . The very laws of complexity . . . suggest that democracy has evolved as perhaps the optimal mechanism to achieve the best attainable compromises among conflicting practical, political, and moral interests."

Kauffman will undoubtedly be accused of Panglosian optimism. After all, Nazi Germany, Larry Flynt, and the AIDS virus are all products of spontaneous order, aren't they? Won?t some outside, judgmental intervention always be necessary in both biological and social systems? Yet whatever the criticisms, Kauffman appears to have introduced a new paradigm into the biological and social sciences. Order is not something that must be imposed or directed from without. It can and does emerge spontaneously from the interactions among the players themselves.

William Tucker is a journalist living in Brooklyn who has written for Harper's Magazine, The Atlantic Monthly, The American Spectator, The Weekly Standard, The New Republic, and other publications.

Excerpt

The existence of spontaneous order is a stunning challenge to our settled ideas in biology since Darwin. Most biologists have believed for over a century that selection is the sole source of order in biology, that selection alone is the "tinkerer" that drafts the forms. But if the forms selection chooses among were generated by laws of complexity, then selection has always had a handmaiden. It is not, after all, the sole source of order, and organisms are not just tinkered-together contraptions, but expressions of deeper natural laws. If all this is true, what a revision of the Darwinian worldview will lie before us! Not we the accidental, but we the expected.