"This internal logic isn't God, Nagel is careful to say, it is not to be found in religion". This is not new, highly regarded scientists have made similar arguments, biochemistry is wired into the universe. The self-made cell emerges from geochemistry as inevitably as basalt or granite."
The odd thing is there actually are scientists—respected ones, Nobel Prize-winning ones—who are saying exactly what Nagel said, and have been saying it for decades. Strangely enough, Nagel doesn't mention them. Yet some scientists think that increases in complexity also happen "actively," that is, driven by physical laws that directly favor increases in complexity.
1). "Life is almost bound to arise, in a molecular form not very different from its form on Earth," wrote Christian de Duve, a Nobel laureate in physiology or medicine, in 1995.
2)Robert Hazen, a mineralogist and biogeologist at the Carnegie Institution for Science, struck a similar note in 2007: "With autotrophy, biochemistry is wired into the universe. The self-made cell emerges from geochemistry as inevitably as basalt or granite."
3)Harold J. Morowitz, a biophysicist at George Mason University, argued that evolution has an arrow built into it: "We start with observations, and if the evolving cosmos has an observed direction, rejecting that view is clearly nonempirical. There need not necessarily be a knowable end point, but there may be an arrow."
Nagel discusses none of that work. He asserts only that evolution is directional, without making a case for it. That has left him open to a number of obvious rebuttals.
4)The biologist H. Allen Orr, at the University of Rochester, pointed out that some species become less complex—parasites, for example, after learning how to steal resources from their hosts. And many species, such as sharks, have been happy to stay just the way they are for millions of years. Only one species—us—has bothered to reach sentience. "The point is," Orr wrote in The New York Review of Books, "that if nature has goals, it certainly seems to have many and consciousness would appear to be fairly far down on the list."
Indeed, biologists usually argue that when you do get progress, it came about by accident.
When you have millions of species taking random walks through the wilds of genetic variation and natural selection, some will, by the luck of the draw, become more complex and more capable. That is, when there is an overall increase in variance, some of the variants will be more complex and capable than their ancestors. Biologists say that such ascents in complexity happen "passively."
Yet some scientists think that increases in complexity also happen "actively," that is, driven by physical laws that directly favor increases in complexity. As a group, these scientists have no sympathy for intelligent design. However, they do see reasons to think that seen as a whole, life does go from simple to complex, from instinctual to intellectual. And they are asking if there are fundamental laws of nature that make it happen.
4) Perhaps the best known of these scientists is Stuart Kauffman, of the Santa Fe Institute, who argues that the universe gives us "order for free." Kauffman has spent decades on origin-of-life research, aiming to show that the transition from chemistry to metabolism is as inevitable as a ball rolling down a slope. Molecules on the early earth, he suggests, inevitably began to catalyze themselves in self-sustaining reactions ("autocatalytic networks"), converting energy and raw materials into increasingly complex structures that eventually crossed the boundary between nonliving and living. Nagel mentions his work once, briefly, in a footnote.
Kauffman has plenty of company.
5) The paleontologist Simon Conway Morris, at the University of Cambridge, has argued that natural structures such as eyes, neurons, brains, and hands are so beneficial that they will get invented over and over again. They are, in effect, attractors in an abstract biological space that pull life in their direction. Contingency and catastrophe will delay them but cannot stop them. Conway Morris sees this as evidence that not only life but human life, and humanlike minds, will emerge naturally from the cosmos: "If we humans had not evolved, then something more or less identical would have emerged sooner or later."
Other biologists are proposing laws that would explain evolutionary ascent in fundamental terms.
6) Daniel McShea and Robert Brandon, a biologist and a philosopher of science, respectively, at Duke University, have argued for what they call a "zero-force evolutionary law," which posits that diversity and complexity will necessarily increase even without environmental change. The chemist Addy Pross, at Ben-Gurion University of the Negev, in Israel, argues that life exhibits "dynamic kinetic stability," in which self-replicating systems become more stable through becoming more complex—and are therefore inherently driven to do so.
Still other scientists have asked how we could measure increases in complexity without being biased by our human-centric perspective.
7) Robert Hazen, working with the Nobel Prize winner Jack Szostak, has proposed a metric he calls "functional information," which measures the number of functions and relationships an organism has relative to its environment.
8) The Harvard astrophysicist Eric Chaisson has proposed measuring a quantity that he calls "energy-rate density": how much energy flows through one gram of a system per second. He argues that when he plots energy-rate density against the emergence of new species, the clear result is an overall increase in complexity over time.
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While the jury is most definitely out on whether these proposed laws and measures are right or wrong (and if right, whether they are profound or trivial), this is a body of work that Nagel could have drawn upon in making his argument. He apparently felt it was acceptable to ignore the science. "Philosophy cannot generate such explanations," he wrote; "it can only point out the gaping lack of them." But there is no gaping lack of attempts to supply them. "He's done so little serious homework," says Michael Ruse. "He just dismisses origin-of-life studies without any indication that he's done any work on it whatsoever."
In short, Mind and Cosmos is not only negative but underpowered, as if Nagel had brought a knife to a shootout. (He declines to comment, telling me by e-mail, "I have a longstanding aversion to interviews.")
But Nagel's goal was valid: to point out that fundamental questions of origins, evolution, and intelligence remain unanswered, and to question whether current ways of thinking are up to the task. A really good book on this subject would need to be both scientific and philosophical: scientific to show what is known, philosophical to show how to go beyond what is known. (A better term might be "metascientific," that is, talking about the science and about how to make new sciences.)
The pieces of this book are scattered about the landscape, in a thousand scraps of ideas from biologists, physicists, physicians, chemists, mathematicians, journalists, public intellectuals, and philosophers. But no book has yet emerged that is mighty enough to shove aside the current order, persuading scientists and nonscientists alike, sparking new experiments, changing syllabi, rejiggering budget priorities, spawning new departments, and changing human language and ways of thought forever. On the Origin of Species did it in 1859. We await the next Darwin.
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