Intelligent design
Intelligent design (ID) approaches evolution by hypothesizing that life is the product of an" intelligent designer". ID is in direct opposition to theory of evolution originally proposed by Charles Darwin and accepted by virtually all modern biologists.
Proponents of ID claim that it is different from creationism, because ID neither begins with the faith that God exists or that God did create the world and living things. Rather ID proponents argue that the various forms of life show signs of having been created.
Opponents of ID tend to dismiss ID's claim of differentiation from creationism, seeing it as a way of dressing up religious claims in scientific guise. Some opponents of ID say it serves primarily as a big tent under which to rally all sorts of creationists; the godfather of the ID movement, the UC Berkeley law professor Phillip Johnson (now emeritus), is quoted as saying that issues such as the age of the earth can be taken up once the common enemy of evolution has been done away with.
A key problem for opponents of ID is that ID does not explain where the "intelligent designer" comes from. These opponents say that instead of reducing the problem of evolution it has greatly expanded it and made it much more difficult, since now explanations have to cover a newly introduced supernatural entity while evolution does not need to.
Intelligent Design differs from creationism on two closely related points.
- First, ID is silent regarding geologists' estimates for the age of the Earth (billions of years), while Biblical literalists say the earth was created only 6,000 years ago. Many ID proponents are old-earth creationists, who accept the antiquity of the Earth, but some, e.g. John Mark Reynolds and Paul Nelson, are young-earth creationists.
- Second, ID is silent regarding biologists' estimates of when the various species of life appeared and disappeared, according to the fossil record, although many proponents of ID express willingness to agree with them, while others, especially young-earth creationists (including Biblical literalists), disagree.
ID agrees to some extent with the theory of evolution, accepting the principle that after a new species has come into existence, its survival or extinction depends on its ability to compete with other forms of life (see natural selection). However, ID adherents immediately part company with evolutionists over this same point.
ID adherents and evolutionists alike believe that small changes can accumulate to create distinctions of breeds, such as Chiuhuahua and Saint Bernard. But evolutionists believe these changes can lead to the establishment of a new species, while ID adherents claim that this is impossible. This is the biggest difference between intelligent design and the theory of evolution, and apparently an irreconcilable one.
Intelligent Design and the Theory of Evolution
The generally accepted view of evolution is based on two premises. Variations occur in the genetic makeup of organisms, and through the process of natural selection, the most fit of those variations survive while the others eventually die out. (There are other forces at work in evolution, e.g., genetic drift, but it is natural selection plus random mutation that typically are criticized by ID proponents.) Intelligent design differs from the rest of creationism by agreeing somewhat with Darwinian evolution.
Intelligent Design accepts much of evolutionary theory, but differs in one crucial aspect -- it insists that there is empirical evidence that an intelligent designer or designer has been at work in the history of life. ID proponents are typically avoid identifying the designer, but for most of them there is no serious doubt that it is the Judeo-Christian concept of God.
ID accepts that fact that there has been microevolution, i.e., populations of species have changed and diverged over time. It may or may not accept that there is speciation, the creation of more than one species out of a single species. Some proponents of ID accept the fossil record as an accurate representation of the history of the evolution of species, and accept that analysis of the fossil record gives accurate and useful results; others do not.
It accepts that there is a process of natural selection, although it may insist that the results of this process must be limited. Once the variation has been caused due to deliberate acts of God, or the unnamed intelligent designer, the survival or extinction of a newly arisen species is believed to then be subject to natural selection, although further acts of God are not ruled out.
Scientific vs ID views
In the scientific view, genetic variations occur randomly, and environmental stress selects against those variations that are not as advantageous as others. In the Intelligent Design viewpoint, these random variations exist but are not the explanation for the appearance of new species. Instead, new species arise when God steps in and causes significant variation to occur. (Actually, this expresses what's usually called progressive creationism)
Adherents of Intelligent Design call the idea that God causes new species to come into being a viable scientific hypothesis (see scientific creationism). Nearly all scientists consider it pseudo-scientific [pseudoscientific?], on the grounds that it is an amalgam of false or unsupported claims within the realm of science and of philosophical or religious claims which are outside the realm of science.
To underscore the pseudo-scientific nature of ID, in the mid-1990s George W. Gilchrist of the University of Washington looked through thousands of scientific journals searching for any articles on intelligent design or creation science -- he didn't find any. Other more recent surveys have also failed to find articles on these subjects in the primary scientific literature (not to mention that only a handful of these articles were even submitted).
Advocates of intelligent design argue that the biological evidence presents serious problems for macroevolution. For example, they claim that all the major types of animals appeared at the same time in the fossil record, with no evidence of common ancestry--a pattern they say is inconsistent with Darwin's theory of evolution. However, modern evolutionary biologists' concept of evolution goes beyond the gradual mechanism proposed by Darwin in the 19th century. Better evidence gathered since the time of Darwin has shown that evolution occurs at a steady Darwinian rate until a large environmental change occurs (such as an ice age, asteroid impact, or very large volcanic eruption). Evolution then occurs at a greatly accelerated rate. Those that adhere to the concept of intelligent design seem to ignore the modern concept of evolution, say many scientists.
They also argued that complex organs that cannot function without all their parts provide evidence for a cause having intelligence. Usually, this intelligence is attributed to God. This may be considered an outgrowth of the idea, held by some, that some biological developments are too complex to have come about without having been designed. This idea is particularly pressed by Michael J. Behe under the rubric irreducible complexity in his Darwin's Black Box (1996; see reference above). See also : argument from design.
Proponents of Intelligent Design point to complex biological structures such as the eye, birds' wings, the existence of mitochondria, etc., arguing that such structures could not possibly have developed due purely to random mutations, even with the aid of natural selection. Symbiotic relationships, such as plants who can only be pollinated by a specific species of insect, which in turn can only reproduce by using the plant, could not have arisen, they argue--a typical chicken-and-egg problem. It is argued that these kinds of biological features are by their very nature too interdependent to come into existence independently through a natural process and then become so intricately intertwined.
Intelligent design does not necessarily claim that living things came together suddenly in their present form through the efforts of a supernatural creator. William A. Dembski, a major ID writer, has claimed that intelligent design is not a doctrine of creation. Intelligent design merely concerns itself with features of natural objects that reliably signal the action of an intelligence, whatever that intelligence might be.
Criticism of Intelligent Design
Some Intelligent Design arguments fall to later scientific study, critics say. For example, the development of mitochondria was once puzzling, but Lynn Margulis's theory of their evolution from endosymbiotic bacteria, once rejected even by biologists, has amassed enough evidence that it is now widely accepted. Evolutionary development of such structures as eyes and wings has been simulated in computers. Studies of fig wasps have revealed how symbiotic species can evolve.
In 1802 theologian William Paley wrote that if a pocket watch is found on a field, it is most reasonable to assume that someone dropped it and that it was made by a watch maker and not by natural forces. Paley went on to argue that complex structures of living things must be the work of an intelligent designer because they are too complex to work half-evolved. Many early creationists cited the human eye as their prime example of this principle; what use is half an eye?, they asked. Evolutionists would provide a detailed explanation for this and would state that creationists were simply falling into the logical fallacy called lack of imagination. Here is the modern view on how eyes have resolved:
The apparent "miracle" of the human eye, along with other body parts and organs, has often been used as proof by both creationists and intelligent design proponents that a higher power must be responsible for creating such a complex organ. Scientists, however, have devised working hypotheses on how certain body parts and organs have evolved.
For example, many biological cells not associated with the senses respond to the presence of light. Most notable of this group are photosynthetic cells of algae and plants. Other very primitive organisms have very rudimentary photoreceptive cells that can only tell the difference between light and dark. These organisms use this primitive sense to orient themselves correctly toward light. Yet other organisms have clusters of these photoreceptive cells that can distinguish crude shapes. Increasing the complexity, number and arrangement of these cells will then yield rudimentary eyes that can recognize certain objects by shape and so on until an eye capable of seeing in color and three dimensions is produced (this has happened at least twice in evolution with the advent of the cephalopod eye and is currently under way with many other animal groups). Each of these steps in the development of a fully functioning eye has modern analogues in the animal kingdom, and each step need only develop through nothing more than natural selection: those animals with a better ability to sense their environment with photoreceptive cells will survive to produce more young than those that don't have this ability, and so on. There is no need for divine intervention of intelligent design, say scientists.
Richard Dawkins in particular has vigorously challenged this aspect of ID (as well as the "impossibility" of natural selection producing symbiotic relationships). Furthermore, he points out that a hypothetical evolutionary path such as that given above for the eye need not even be correct; in order to refute the argument from design it need only be plausible, thus demonstrating that there are other ways in which such an organ could have come about. The title of Dawkins' book The Blind Watchmaker is a reference to Paley's example of the pocket watch.
Other body parts and organ systems that ID mentions could only have arisen through intelligent design have similar scientifically valid explanations. Further, say scientists, a body part or organ that has a modern function does not necessarily have to had the same function in the past. Evolution works on chance and opportunity, they say, with gill bones of mouth-less fishes evolving into jaws, fish air bladders becoming vertebrate lungs, and fin support structures becoming fingers and toes.
However, the term "intelligent design" has a broader usage than that given in the Intelligent Design Theory. It can refer simply to the belief that God designed the universe, without any specific claim as to how or when he did so. Many people consider this belief entirely compatible with standard Darwinian evolution, with no divine intervention -- life could be produced by a purely natural process, evolution, designed by God. God might merely have written the laws of physics, or chosen the fundamental constants, and left the universe to run like clockwork afterwards. This would be a form of deism. The belief that the laws of the universe were constructed to allow for the existence of intelligent life is known as the Anthropic Cosmological Principle. A more theologically robust view is theistic evolution (see e.g. Kenneth R. Miller's ""Finding Darwin's God"" cited above), where, far from being a hands-off deity, God continually oversees and sustains the processes of evolution.
Not all people who believe that God was involved in the design of the Universe also adhere to the specifics of the Intelligent Design belief as proposed by Creationists.
Intelligent Design has lately been a controversial subject, particularly in American schools. After years of judicial rejection of Creationist teaching--on the grounds that Creationism is a religious, not a scientific theory--many Creationists have begun to promote Intelligent Design as a non-religious, scientifically acceptable alternative to the theory of Evolution. However, this attempt has met with strong opposition from some theologians. In order to be non-religious, one must argue that the intelligent being who designed the universe is not necessarily the same as the religious God. This view has been criticized as allowing for the existence of a demiurge and for being perilously close to Gnosticism, which is considered heretical by most Christian groups.
See: Creationism, evolution, theory of evolution, falsifiability, protoscience, pseudoscience, irreducible complexity, Argument from evolution
Further Reading:
- Michael J. Behe: Darwin's Black Box: The Biochemical Challenge to Evolution, Free Press 1996. Argues that several exquisite biochemical mechanisms could not have arisen by a sequence of random mutations and selection.
- Ernst Mayr: One Long Argument: Charles Darwin and the Genesis of Modern Evolutionary Thought, Harvard University Press 1993. Explanation of the evidence behind the mainstream evolutionary theory.
- Kenneth R. Miller: Finding Darwin's God, HarperCollins 1999. A cell biologist (and devout Christian) pokes holes in intelligent design theory.
- Robert T. Pennock: Tower of Babel: The Evidence against the New Creationism, MIT Press 1999. A philosopher pokes holes in intelligent design theory.
- Intelligent Design Creationism and its Critics, ed. Robert T. Pennock, MIT Press 2002. A comprehensive anthology.
External links:
- Entry about Intelligent Design in the "The Skeptic's Dictionary" by Robert Todd Carroll:
- Intelligent Design FAQ
- See also : Tim Berra