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A great article from the New Yorker which rationally explains why the Creationists latest attempts to pass off creationism under a different name (this time they're calling it "Intelligent Design") is being laughed at by the scientific community. Intelligent design is the work of two men who's goal was to save as much of biblical creationism as possible while still acknowledging scientific advances which proved previous creationist dogma was false (the young earth "theory", the six day creation "theory", etc...). This is a great article.
DEVOLUTION
by H. ALLEN ORR
Why intelligent design isn’t.
Issue of 2005-05-30
Posted 2005-05-23
If you are in ninth grade and live in Dover, Pennsylvania, you are learning things in your biology class that differ considerably from what your peers just a few miles away are learning. In particular, you are learning that Darwin’s theory of evolution provides just one possible explanation of life, and that another is provided by something called intelligent design. You are being taught this not because of a recent breakthrough in some scientist’s laboratory but because the Dover Area School District’s board mandates it. In October, 2004, the board decreed that “students will be made aware of gaps/problems in Darwin’s theory and of other theories of evolution including, but not limited to, intelligent design.”
While the events in Dover have received a good deal of attention as a sign of the political times, there has been surprisingly little discussion of the science that’s said to underlie the theory of intelligent design, often called I.D. Many scientists avoid discussing I.D. for strate
gic reasons. If a scientific claim can be loosely defined as one that scientists take seriously enough to debate, then engaging the intelligent-design movement on scientific grounds, they worry, cedes what it most desires: recognition that its claims are legitimate scientific ones.
Meanwhile, proposals hostile to evolution are being considered in more than twenty states; earlier this month, a bill was introduced into the New York State Assembly calling for instruction in intelligent design for all public-school students. The Kansas State Board of Education is weighing new standards, drafted by supporters of intelligent design, that would encourage schoolteachers to challenge Darwinism. Senator Rick Santorum, a Pennsylvania Republican, has argued that “intelligent design is a legitimate scientific theory that should be taught in science classes.” An I.D.-friendly amendment that he sponsored to the No Child Left Behind Act—requiring public schools to help students understand why evolution “generates so much continuing controversy”—was overwhelmingly approved in the Senate. (The amendment was not included in the version of the bill that was signed into law, but similar language did appear in a conference report that accompanied it.) In the past few years, college students across the country have formed Intelligent Design and Evolution Awareness chapters. Clearly, a policy of limited scientific engagement has failed. So just what is this movement?
First of all, intelligent design is not what people often assume it is. For one thing, I.D. is not Biblical literalism. Unlike earlier generations of creationists—the so-called Young Earthers and scientific creationists—proponents of intelligent design do not believe that the universe was created in six days, that Earth is ten thousand years old, or that the fossil record was deposited during Noah’s flood. (Indeed, they shun the label “creationism” altogether.) Nor does I.D. flatly reject evolution: adherents freely admit that some evolutionary change occurred during the history of life on Earth. Although the movement is loosely allied with, and heavily funded by, various conservative Christian groups—and although I.D. plainly maintains that life was created—it is generally silent about the identity of the creator.
The movement’s main positive claim is that there are things in the world, most notably life, that cannot be accounted for by known natural causes and show features that, in any other context, we would attribute to intelligence. Living organisms are too complex to be explained by any natural—or, more precisely, by any mindless—process. Instead, the design inherent in organisms can be accounted for only by invoking a designer, and one who is very, very smart.
All of which puts I.D. squarely at odds with Darwin. Darwin’s theory of evolution was meant to show how the fantastically complex features of organisms—eyes, beaks, brains—could arise without the intervention of a designing mind. According to Darwinism, evolution largely reflects the combined action of random mutation and natural selection. A random mutation in an organism, like a random change in any finely tuned machine, is almost always bad. That’s why you don’t, screwdriver in hand, make arbitrary changes to the insides of your television. But, once in a great while, a random mutation in the DNA that makes up an organism’s genes slightly improves the function of some organ and thus the survival of the organism. In a species whose eye amounts to nothing more than a primitive patch of light-sensitive cells, a mutation that causes this patch to fold into a cup shape might have a survival advantage. While the old type of organism can tell only if the lights are on, the new type can detect the direction of any source of light or shadow. Since shadows sometimes mean predators, that can be valuable information. The new, improved type of organism will, therefore, be more common in the next generation. That’s natural selection. Repeated over billions of years, this process of incremental improvement should allow for the gradual emergence of organisms that are exquisitely adapted to their environments and that look for all the world as though they were designed. By 1870, about a decade after “The Origin of Species” was published, nearly all biologists agreed that life had evolved, and by 1940 or so most agreed that natural selection was a key force driving this evolution.
Advocates of intelligent design point to two developments that in their view undermine Darwinism. The first is the molecular revolution in biology. Beginning in the nineteen-fifties, molecular biologists revealed a staggering and unsuspected degree of complexity within the cells that make up all life. This complexity, I.D.’s defenders argue, lies beyond the abilities of Darwinism to explain. Second, they claim that new mathematical findings cast doubt on the power of natural selection. Selection may play a role in evolution, but it cannot accomplish what biologists suppose it can.
These claims have been championed by a tireless group of writers, most of them associated with the Center for Science and Culture at the Discovery Institute, a Seattle-based think tank that sponsors projects in science, religion, and national defense, among other areas. The center’s fellows and advisers—including the emeritus law professor Phillip E. Johnson, the philosopher Stephen C. Meyer, and the biologist Jonathan Wells—have published an astonishing number of articles and books that decry the ostensibly sad state of Darwinism and extoll the virtues of the design alternative. But Johnson, Meyer, and Wells, while highly visible, are mainly strategists and popularizers. The scientific leaders of the design movement are two scholars, one a biochemist and the other a mathematician. To assess intelligent design is to assess their arguments.
Michael J. Behe, a professor of biological sciences at Lehigh University (and a senior fellow at the Discovery Institute), is a biochemist who writes technical papers on the structure of DNA. He is the most prominent of the small circle of scientists working on intelligent design, and his arguments are by far the best known. His book “Darwin’s Black Box” (1996) was a surprise best-seller and was named by National Review as one of the hundred best nonfiction books of the twentieth century. (A little calibration may be useful here; “The Starr Report” also made the list.)
Not surprisingly, Behe’s doubts about Darwinism begin with biochemistry. Fifty years ago, he says, any biologist could tell stories like the one about the eye’s evolution. But such stories, Behe notes, invariably began with cells, whose own evolutionary origins were essentially left unexplained. This was harmless enough as long as cells weren’t qualitatively more complex than the larger, more visible aspects of the eye. Yet when biochemists began to dissect the inner workings of the cell, what they found floored them. A cell is packed full of exceedingly complex structures—hundreds of microscopic machines, each performing a specific job. The “Give me a cell and I’ll give you an eye” story told by Darwinists, he says, began to seem suspect: starting with a cell was starting ninety per cent of the way to the finish line.
Behe’s main claim is that cells are complex not just in degree but in kind. Cells contain structures that are “irreducibly complex.” This means that if you remove any single part from such a structure, the structure no longer functions. Behe offers a simple, nonbiological example of an irreducibly complex object: the mousetrap. A mousetrap has several parts—platform, spring, catch, hammer, and hold-down bar—and all of them have to be in place for the trap to work. If you remove the spring from a mousetrap, it isn’t slightly worse at killing mice; it doesn’t kill them at all. So, too, with the bacterial flagellum, Behe argues. This flagellum is a tiny propeller attached to the back of some bacteria. Spinning at more than twenty thousand r.p.m.s, it motors the bacterium through its aquatic world. The flagellum comprises roughly thirty different proteins, all precisely arranged, and if any one of them is removed the flagellum stops spinning.
In “Darwin’s Black Box,” Behe maintained that irreducible complexity presents Darwinism with “unbridgeable chasms.” How, after all, could a gradual process of incremental improvement build something like a flagellum, which needs all its parts in order to work? Scientists, he argued, must face up to the fact that “many biochemical systems cannot be built by natural selection working on mutations.” In the end, Behe concluded that irreducibly complex cells arise the same way as irreducibly complex mousetraps—someone designs them. As he put it in a recent Times Op-Ed piece: “If it looks, walks, and quacks like a duck, then, absent compelling evidence to the contrary, we have warrant to conclude it’s a duck. Design should not be overlooked simply because it’s so obvious.” In “Darwin’s Black Box,” Behe speculated that the designer might have assembled the first cell, essentially solving the problem of irreducible complexity, after which evolution might well have proceeded by more or less conventional means. Under Behe’s brand of creationism, you might still be an ape that evolved on the African savanna; it’s just that your cells harbor micro-machines engineered by an unnamed intelligence some four billion years ago.
But Behe’s principal argument soon ran into trouble. As biologists pointed out, there are several different ways that Darwinian evolution can build irreducibly complex systems. In one, elaborate structures may evolve for one reason and then get co-opted for some entirely different, irreducibly complex function. Who says those thirty flagellar proteins weren’t present in bacteria long before bacteria sported flagella? They may have been performing other jobs in the cell and only later got drafted into flagellum-building. Indeed, there’s now strong evidence that several flagellar proteins once played roles in a type of molecular pump found in the membranes of bacterial cells.
Behe doesn’t consider this sort of “indirect” path to irreducible complexity—in which parts perform one function and then switch to another—terribly plausible. And he essentially rules out the alternative possibility of a direct Darwinian path: a path, that is, in which Darwinism builds an irreducibly complex structure while selecting all along for the same biological function. But biologists have shown that direct paths to irreducible complexity are possible, too. Suppose a part gets added to a system merely because the part improves the system’s performance; the part is not, at this stage, essential for function. But, because subsequent evolution builds on this addition, a part that was at first just advantageous might become essential. As this process is repeated through evolutionary time, more and more parts that were once merely beneficial become necessary. This idea was first set forth by H. J. Muller, the Nobel Prize-winning geneticist, in 1939, but it’s a familiar process in the development of human technologies. We add new parts like global-positioning systems to cars not because they’re necessary but because they’re nice. But no one would be surprised if, in fifty years, computers that rely on G.P.S. actually drove our cars. At that point, G.P.S. would no longer be an attractive option; it would be an essential piece of automotive technology. It’s important to see that this process is thoroughly Darwinian: each change might well be small and each represents an improvement.
Design theorists have made some concessions to these criticisms. Behe has confessed to “sloppy prose” and said he hadn’t meant to imply that irreducibly complex systems “by definition” cannot evolve gradually. “I quite agree that my argument against Darwinism does not add up to a logical proof,” he says—though he continues to believe that Darwinian paths to irreducible complexity are exceedingly unlikely. Behe and his followers now emphasize that, while irreducibly complex systems can in principle evolve, biologists can’t reconstruct in convincing detail just how any such system did evolve.
What counts as a sufficiently detailed historical narrative, though, is altogether subjective. Biologists actually know a great deal about the evolution of biochemical systems, irreducibly complex or not. It’s significant, for instance, that the proteins that typically make up the parts of these systems are often similar to one another. (Blood clotting—another of Behe’s examples of irreducible complexity—involves at least twenty proteins, several of which are similar, and all of which are needed to make clots, to localize or remove clots, or to prevent the runaway clotting of all blood.) And biologists understand why these proteins are so similar. Each gene in an organism’s genome encodes a particular protein. Occasionally, the stretch of DNA that makes up a particular gene will get accidentally copied, yielding a genome that includes two versions of the gene. Over many generations, one version of the gene will often keep its original function while the other one slowly changes by mutation and natural selection, picking up a new, though usually related, function. This process of “gene duplication” has given rise to entire families of proteins that have similar functions; they often act in the same biochemical pathway or sit in the same cellular structure. There’s no doubt that gene duplication plays an extremely important role in the evolution of biological complexity.
It’s true that when you confront biologists with a particular complex structure like the flagellum they sometimes have a hard time saying which part appeared before which other parts. But then it can be hard, with any complex historical process, to reconstruct the exact order in which events occurred, especially when, as in evolution, the addition of new parts encourages the modification of old ones. When you’re looking at a bustling urban street, for example, you probably can’t tell which shop went into business first. This is partly because many businesses now depend on each other and partly because new shops trigger changes in old ones (the new sushi place draws twenty-somethings who demand wireless Internet at the café next door). But it would be a little rash to conclude that all the shops must have begun business on the same day or that some Unseen Urban Planner had carefully determined just which business went where.
by H. ALLEN ORR
Why intelligent design isn’t.
Issue of 2005-05-30
Posted 2005-05-23
If you are in ninth grade and live in Dover, Pennsylvania, you are learning things in your biology class that differ considerably from what your peers just a few miles away are learning. In particular, you are learning that Darwin’s theory of evolution provides just one possible explanation of life, and that another is provided by something called intelligent design. You are being taught this not because of a recent breakthrough in some scientist’s laboratory but because the Dover Area School District’s board mandates it. In October, 2004, the board decreed that “students will be made aware of gaps/problems in Darwin’s theory and of other theories of evolution including, but not limited to, intelligent design.”
While the events in Dover have received a good deal of attention as a sign of the political times, there has been surprisingly little discussion of the science that’s said to underlie the theory of intelligent design, often called I.D. Many scientists avoid discussing I.D. for strate
gic reasons. If a scientific claim can be loosely defined as one that scientists take seriously enough to debate, then engaging the intelligent-design movement on scientific grounds, they worry, cedes what it most desires: recognition that its claims are legitimate scientific ones.
Meanwhile, proposals hostile to evolution are being considered in more than twenty states; earlier this month, a bill was introduced into the New York State Assembly calling for instruction in intelligent design for all public-school students. The Kansas State Board of Education is weighing new standards, drafted by supporters of intelligent design, that would encourage schoolteachers to challenge Darwinism. Senator Rick Santorum, a Pennsylvania Republican, has argued that “intelligent design is a legitimate scientific theory that should be taught in science classes.” An I.D.-friendly amendment that he sponsored to the No Child Left Behind Act—requiring public schools to help students understand why evolution “generates so much continuing controversy”—was overwhelmingly approved in the Senate. (The amendment was not included in the version of the bill that was signed into law, but similar language did appear in a conference report that accompanied it.) In the past few years, college students across the country have formed Intelligent Design and Evolution Awareness chapters. Clearly, a policy of limited scientific engagement has failed. So just what is this movement?
First of all, intelligent design is not what people often assume it is. For one thing, I.D. is not Biblical literalism. Unlike earlier generations of creationists—the so-called Young Earthers and scientific creationists—proponents of intelligent design do not believe that the universe was created in six days, that Earth is ten thousand years old, or that the fossil record was deposited during Noah’s flood. (Indeed, they shun the label “creationism” altogether.) Nor does I.D. flatly reject evolution: adherents freely admit that some evolutionary change occurred during the history of life on Earth. Although the movement is loosely allied with, and heavily funded by, various conservative Christian groups—and although I.D. plainly maintains that life was created—it is generally silent about the identity of the creator.
The movement’s main positive claim is that there are things in the world, most notably life, that cannot be accounted for by known natural causes and show features that, in any other context, we would attribute to intelligence. Living organisms are too complex to be explained by any natural—or, more precisely, by any mindless—process. Instead, the design inherent in organisms can be accounted for only by invoking a designer, and one who is very, very smart.
All of which puts I.D. squarely at odds with Darwin. Darwin’s theory of evolution was meant to show how the fantastically complex features of organisms—eyes, beaks, brains—could arise without the intervention of a designing mind. According to Darwinism, evolution largely reflects the combined action of random mutation and natural selection. A random mutation in an organism, like a random change in any finely tuned machine, is almost always bad. That’s why you don’t, screwdriver in hand, make arbitrary changes to the insides of your television. But, once in a great while, a random mutation in the DNA that makes up an organism’s genes slightly improves the function of some organ and thus the survival of the organism. In a species whose eye amounts to nothing more than a primitive patch of light-sensitive cells, a mutation that causes this patch to fold into a cup shape might have a survival advantage. While the old type of organism can tell only if the lights are on, the new type can detect the direction of any source of light or shadow. Since shadows sometimes mean predators, that can be valuable information. The new, improved type of organism will, therefore, be more common in the next generation. That’s natural selection. Repeated over billions of years, this process of incremental improvement should allow for the gradual emergence of organisms that are exquisitely adapted to their environments and that look for all the world as though they were designed. By 1870, about a decade after “The Origin of Species” was published, nearly all biologists agreed that life had evolved, and by 1940 or so most agreed that natural selection was a key force driving this evolution.
Advocates of intelligent design point to two developments that in their view undermine Darwinism. The first is the molecular revolution in biology. Beginning in the nineteen-fifties, molecular biologists revealed a staggering and unsuspected degree of complexity within the cells that make up all life. This complexity, I.D.’s defenders argue, lies beyond the abilities of Darwinism to explain. Second, they claim that new mathematical findings cast doubt on the power of natural selection. Selection may play a role in evolution, but it cannot accomplish what biologists suppose it can.
These claims have been championed by a tireless group of writers, most of them associated with the Center for Science and Culture at the Discovery Institute, a Seattle-based think tank that sponsors projects in science, religion, and national defense, among other areas. The center’s fellows and advisers—including the emeritus law professor Phillip E. Johnson, the philosopher Stephen C. Meyer, and the biologist Jonathan Wells—have published an astonishing number of articles and books that decry the ostensibly sad state of Darwinism and extoll the virtues of the design alternative. But Johnson, Meyer, and Wells, while highly visible, are mainly strategists and popularizers. The scientific leaders of the design movement are two scholars, one a biochemist and the other a mathematician. To assess intelligent design is to assess their arguments.
Michael J. Behe, a professor of biological sciences at Lehigh University (and a senior fellow at the Discovery Institute), is a biochemist who writes technical papers on the structure of DNA. He is the most prominent of the small circle of scientists working on intelligent design, and his arguments are by far the best known. His book “Darwin’s Black Box” (1996) was a surprise best-seller and was named by National Review as one of the hundred best nonfiction books of the twentieth century. (A little calibration may be useful here; “The Starr Report” also made the list.)
Not surprisingly, Behe’s doubts about Darwinism begin with biochemistry. Fifty years ago, he says, any biologist could tell stories like the one about the eye’s evolution. But such stories, Behe notes, invariably began with cells, whose own evolutionary origins were essentially left unexplained. This was harmless enough as long as cells weren’t qualitatively more complex than the larger, more visible aspects of the eye. Yet when biochemists began to dissect the inner workings of the cell, what they found floored them. A cell is packed full of exceedingly complex structures—hundreds of microscopic machines, each performing a specific job. The “Give me a cell and I’ll give you an eye” story told by Darwinists, he says, began to seem suspect: starting with a cell was starting ninety per cent of the way to the finish line.
Behe’s main claim is that cells are complex not just in degree but in kind. Cells contain structures that are “irreducibly complex.” This means that if you remove any single part from such a structure, the structure no longer functions. Behe offers a simple, nonbiological example of an irreducibly complex object: the mousetrap. A mousetrap has several parts—platform, spring, catch, hammer, and hold-down bar—and all of them have to be in place for the trap to work. If you remove the spring from a mousetrap, it isn’t slightly worse at killing mice; it doesn’t kill them at all. So, too, with the bacterial flagellum, Behe argues. This flagellum is a tiny propeller attached to the back of some bacteria. Spinning at more than twenty thousand r.p.m.s, it motors the bacterium through its aquatic world. The flagellum comprises roughly thirty different proteins, all precisely arranged, and if any one of them is removed the flagellum stops spinning.
In “Darwin’s Black Box,” Behe maintained that irreducible complexity presents Darwinism with “unbridgeable chasms.” How, after all, could a gradual process of incremental improvement build something like a flagellum, which needs all its parts in order to work? Scientists, he argued, must face up to the fact that “many biochemical systems cannot be built by natural selection working on mutations.” In the end, Behe concluded that irreducibly complex cells arise the same way as irreducibly complex mousetraps—someone designs them. As he put it in a recent Times Op-Ed piece: “If it looks, walks, and quacks like a duck, then, absent compelling evidence to the contrary, we have warrant to conclude it’s a duck. Design should not be overlooked simply because it’s so obvious.” In “Darwin’s Black Box,” Behe speculated that the designer might have assembled the first cell, essentially solving the problem of irreducible complexity, after which evolution might well have proceeded by more or less conventional means. Under Behe’s brand of creationism, you might still be an ape that evolved on the African savanna; it’s just that your cells harbor micro-machines engineered by an unnamed intelligence some four billion years ago.
But Behe’s principal argument soon ran into trouble. As biologists pointed out, there are several different ways that Darwinian evolution can build irreducibly complex systems. In one, elaborate structures may evolve for one reason and then get co-opted for some entirely different, irreducibly complex function. Who says those thirty flagellar proteins weren’t present in bacteria long before bacteria sported flagella? They may have been performing other jobs in the cell and only later got drafted into flagellum-building. Indeed, there’s now strong evidence that several flagellar proteins once played roles in a type of molecular pump found in the membranes of bacterial cells.
Behe doesn’t consider this sort of “indirect” path to irreducible complexity—in which parts perform one function and then switch to another—terribly plausible. And he essentially rules out the alternative possibility of a direct Darwinian path: a path, that is, in which Darwinism builds an irreducibly complex structure while selecting all along for the same biological function. But biologists have shown that direct paths to irreducible complexity are possible, too. Suppose a part gets added to a system merely because the part improves the system’s performance; the part is not, at this stage, essential for function. But, because subsequent evolution builds on this addition, a part that was at first just advantageous might become essential. As this process is repeated through evolutionary time, more and more parts that were once merely beneficial become necessary. This idea was first set forth by H. J. Muller, the Nobel Prize-winning geneticist, in 1939, but it’s a familiar process in the development of human technologies. We add new parts like global-positioning systems to cars not because they’re necessary but because they’re nice. But no one would be surprised if, in fifty years, computers that rely on G.P.S. actually drove our cars. At that point, G.P.S. would no longer be an attractive option; it would be an essential piece of automotive technology. It’s important to see that this process is thoroughly Darwinian: each change might well be small and each represents an improvement.
Design theorists have made some concessions to these criticisms. Behe has confessed to “sloppy prose” and said he hadn’t meant to imply that irreducibly complex systems “by definition” cannot evolve gradually. “I quite agree that my argument against Darwinism does not add up to a logical proof,” he says—though he continues to believe that Darwinian paths to irreducible complexity are exceedingly unlikely. Behe and his followers now emphasize that, while irreducibly complex systems can in principle evolve, biologists can’t reconstruct in convincing detail just how any such system did evolve.
What counts as a sufficiently detailed historical narrative, though, is altogether subjective. Biologists actually know a great deal about the evolution of biochemical systems, irreducibly complex or not. It’s significant, for instance, that the proteins that typically make up the parts of these systems are often similar to one another. (Blood clotting—another of Behe’s examples of irreducible complexity—involves at least twenty proteins, several of which are similar, and all of which are needed to make clots, to localize or remove clots, or to prevent the runaway clotting of all blood.) And biologists understand why these proteins are so similar. Each gene in an organism’s genome encodes a particular protein. Occasionally, the stretch of DNA that makes up a particular gene will get accidentally copied, yielding a genome that includes two versions of the gene. Over many generations, one version of the gene will often keep its original function while the other one slowly changes by mutation and natural selection, picking up a new, though usually related, function. This process of “gene duplication” has given rise to entire families of proteins that have similar functions; they often act in the same biochemical pathway or sit in the same cellular structure. There’s no doubt that gene duplication plays an extremely important role in the evolution of biological complexity.
It’s true that when you confront biologists with a particular complex structure like the flagellum they sometimes have a hard time saying which part appeared before which other parts. But then it can be hard, with any complex historical process, to reconstruct the exact order in which events occurred, especially when, as in evolution, the addition of new parts encourages the modification of old ones. When you’re looking at a bustling urban street, for example, you probably can’t tell which shop went into business first. This is partly because many businesses now depend on each other and partly because new shops trigger changes in old ones (the new sushi place draws twenty-somethings who demand wireless Internet at the café next door). But it would be a little rash to conclude that all the shops must have begun business on the same day or that some Unseen Urban Planner had carefully determined just which business went where.
created the universe
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