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Irreducible complexity is a controversial concept invoked in support of Intelligent Design which claims that the generally accepted Scientific Theory that Life evolved through biological Evolution by Natural Selection is incomplete and flawed and that the intervention of an Intelligent Designer is required to explain the origins of life. An ''' Irreducibly Complex ''' system is defined as one that could not function if it were any simpler, and therefore could not possibly have been formed by successive additions to a precursor system with the same functionality. The concept was popularized by Lehigh University Biochemist and Fellow of the Discovery Institute Michael Behe in his 1996 book '' Darwin's Black Box '', wherein Behe argued that there are biochemical systems which are "irreducibly complex" because he saw no way in which these systems could be broken down into smaller functioning systems. With this argument, the book in effect supports what is known as Intelligent Design , a form of the Argument From Design , which is one of the arguments for the existence of a Supernatural Deity . In 2001, , Behe fails to provide a testable Hypothesis , and there is a lack of evidence in support of the concept. As such, irreducible complexity is seen by the supporters of Evolutionary Theory as an example of Creationist Pseudoscience , amounting to a God Of The Gaps argument. In the 2005 IRREDUCIBLE COMPLEXITY (IC) An early concept of irreducibly complex systems comes from systems in order to fully understand how they work. He extended his work on biological complexity into a general theory of systems in a book titled '' General Systems Theory ''. After James Watson and Francis Crick published the structure of DNA in the early 1950s, General Systems Theory lost many of its adherents in the physical and biological sciences. Jacques Monod 's ''Chance and Necessity'' provides a good discussion of the "triumph" of the mechanistic view in biochemistry. Systems theory remained popular among social sciences long after its demise in the physical and biological sciences. Michael Behe uses the term "irreducible complexity" in his 1996 book '' Darwin's Black Box '', to refer to certain complex biochemical Cellular systems. He posits that evolutionary mechanisms cannot explain the development of such 'irreducibly complex' systems. Notably, Behe credits philosopher William Paley for the original concept, not von Bertalanffy, and suggests that his application of the concept to biological systems is entirely original. Intelligent design advocates argue that irreducibly complex systems must have been deliberately engineered by some form of intelligence. According to the theory of evolution, genetic variations occur without specific design or intent. The environment "selects" the variants that have the highest fitness, which are then passed on to the next generation of organisms. Change occurs by the gradual operation of natural forces over time, perhaps slowly, perhaps more quickly (see Punctuated Equilibrium ). This process is able to "create" complex structures from simpler beginnings, or convert complex structures from one function to another (see Spandrel ). Most intelligent design advocates accept that evolution occurs through mutation and natural selection at the "micro level," such as changing the relative frequency of various beak lengths in finches, but assert that it cannot account for irreducible complexity, because none of the parts of an irreducible system would be functional or advantageous until the entire system is in place. Behe uses the mousetrap as an illustrative example of this concept. A mousetrap consists of several interacting pieces—the base, the catch, the spring, the hammer—all of which must be in place for the mousetrap to work. The removal of any one piece destroys the function of the mousetrap. Likewise, biological systems require multiple parts working together in order to function. Intelligent design advocates claim that natural selection could not create from scratch those systems for which science is currently not able to find a viable evolutionary pathway of successive, slight modifications, because the selectable function is only present when all parts are assembled. Behe's original examples of irreducibly complex mechanisms included the bacterial Flagellum of '' E. Coli '', the Blood Clotting cascade, Cilia , and the adaptive Immune System . Criticism The irreducible complexity argument also assumes that the necessary parts of a system have always been necessary, and therefore could not have been added sequentially. But something which is at first merely advantageous can later become necessary. For example, one of the clotting factors that Behe listed as a part of the clotting cascade was later found to be absent in whales, demonstrating that it is not essential for a clotting system.1 Many purportedly irreducible structures can be found in other organisms as simpler systems that utilize fewer parts. These systems may have had even simpler precursors that are now extinct. Perhaps most importantly, potentially viable evolutionary pathways have been proposed for allegedly irreducibly complex systems such as blood clotting, the immune systemMatt Inlay, 2002. " Evolving Immunity ." In ''TalkDesign.org''. and the flagellum,Nic J. Matzke, 2003. " Evolution in (Brownian) space: a model for the origin of the bacterial flagellum ." which were the three examples Behe used. Even his example of a mousetrap was shown to be reducible by John H. McDonald.In ''TalkDesign.org'' John H. McDonald A reducibly complex mousetrap . If irreducible complexity is an insurmountable obstacle to evolution, it should not be possible to conceive of such pathways—Behe has remarked that such plausible pathways would defeat his argument. Niall Shanks and Karl H. Joplin have shown that systems satisfying Behe's characterization of irreducible biochemical complexity can arise naturally and spontaneously as the result of self-organizing chemical processes.Niall Shanks and Karl H. Joplin. Redundant Complexity:A Critical Analysis of Intelligent Design in Biochemistry. East Tennessee State University. They also assert that what evolved biochemical and molecular systems actually exhibit is redundant complexity—a kind of complexity that is the product of an Evolved biochemical process. They claim that Behe overestimated the significance of irreducible complexity because his simple, linear view of biochemical reactions results in his taking snapshots of selective features of biological systems, structures and processes, while ignoring the redundant complexity of the context in which those features are naturally embedded and an over-reliance of overly simplistic metaphors such as his mousetrap. In addition, it has been claimed that computer simulations of evolution demonstrate that it is possible for irreducible complexity to evolve naturally.2 It is illustrative to compare a mousetrap with a cat, in this context. Both normally function so as to control the mouse population. The cat has many parts that can be removed leaving it still functional; for example, its tail can be bobbed or it can be spayed. Evolution has endowed it with redundant eyes, so if one eye goes blind, the cat can still catch mice. Comparing the cat and the mousetrap, then, one sees that the mousetrap (which is not alive) offers better evidence, in terms of irreducible complexity, for intelligent design than the cat. DEFINITIONS The term "irreducible complexity" was originally defined by Behe as: : ''A single system which is composed of several interacting parts that contribute to the basic function, and where the removal of any one of the parts causes the system to effectively cease functioning''". ('' Darwin's Black Box '' p9) Supporters of intelligent design use this term to refer to biological systems and organs that they Believe could not have come about by any series of small changes. They argue that anything less than the complete form of such a system or organ would not work ''at all'', or would in fact be a ''detriment'' to the organism, and would therefore never survive the process of natural selection. Although they accept that some complex systems and organs ''can'' be explained by evolution, they claim that organs and biological features which are ''irreducibly complex'' cannot be explained by current models, and that an intelligent designer must have created life or guided its evolution. Accordingly, the debate on irreducible complexity concerns two questions: whether irreducible complexity can be found in nature, and what significance it would have if it did exist in nature. A second definition given by Behe (his "evolutionary definition") is as follows: :''An irreducibly complex evolutionary pathway is one that contains one or more unselected steps (that is, one or more necessary-but-unselected mutations). The degree of irreducible complexity is the number of unselected steps in the pathway. Intelligent design advocate William Dembski gives this definition: :''A system performing a given basic function is irreducibly complex if it includes a set of well-matched, mutually interacting, nonarbitrarily individuated parts such that each part in the set is indispensable to maintaining the system's basic, and therefore original, function. The set of these indispensable parts is known as the irreducible core of the system. (No Free Lunch, 285) STATED EXAMPLES Behe and others have suggested a number of biological features that they believe may be irreducibly complex. Flagella See Also: Evolution of flagella The Flagella of certain bacteria constitute a Molecular Motor requiring the interaction of about 40 complex protein parts, and the absence of any one of these proteins causes the flagella to fail to function. Behe holds that the flagellum "engine" is irreducibly complex because if we try to reduce its complexity by positing an earlier and simpler stage of its evolutionary development, we get an organism which functions improperly. Mainstream scientists regard this argument as having been largely disproved in the light of fairly recent research.Miller, Kenneth R. The Flagellum Unspun: The Collapse of "Irreducible Complexity" with reply here They point out that the basal body of the flagella has been found to be similar to the Type III Secretion System (TTSS), a needle-like structure that pathogenic germs such as Salmonella use to inject Toxin s into living Eucaryote cells. The needle's base has many elements in common with the flagellum, but it is missing most of the proteins that make a flagellum work. Thus, this system seems to negate the claim that taking away any of the flagellum's parts would render it useless. This has caused Miller to note that, "The parts of this supposedly irreducibly complex system actually have functions of their own." Manier, Jeremy [http://www.myrtlebeachonline.com/mld/myrtlebeachonline/news/nation/13896398.htm Unlocking cell secrets bolsters evolutionists] (Chicago Tribune, 2006 Feb 13) Blood clotting cascade The Blood Clotting Cascade in vertebrates is another complex biological pathway that is given as an example of irreducible complexity.Action, George "Behe and the Blood Clotting Cascade" FORERUNNERS The argument from irreducible complexity is a descendant of the Teleological Argument for God (the argument from design or argument from complexity). This states that because certain things in nature are very complicated, they must have been designed, just as the existence of a watch implies the existence of a watchmaker (in William Paley 's Famous Argument of 1802). This argument has a long history and can be traced back at least as far as Cicero 's ''De natura deorum'', ii. 34 (see Hallam, Literature of Europe, ii. 385, note). While he did not originate the term, Charles Darwin identified the argument as a Testable prediction of the theory of Evolution at the outset. In The Origin Of Species , he wrote, "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case." Darwin's theory of evolution challenges the teleological argument by postulating an alternative explanation to that of an intelligent designer: namely evolution by natural and sexual selection. The argument from irreducible complexity attempts to demonstrate that certain biological features cannot be purely the product of Darwinian evolution. CRITICISMS OF IRREDUCIBLE COMPLEXITY There has been much scientific opposition to the irreducible complexity, with one science writer calling it a "full-blown intellectual surrender strategy."Mirsky, Steve Sticker Shock: In the beginning was the cautionary advisory ''Scientific American'', Feb 2005 It may be that irreducible complexity does not actually exist in nature: that the examples given by Behe and others are not in fact irreducibly complex, but can be explained in terms of simpler precursors. Thus they would either be merely ''very complex'', or they would be misunderstood or misrepresented. |
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