Editing Irreducible complexity (section)

{{Short description|Argument by proponents of intelligent design}}
{{about|the concept in intelligent design|the concept in systems theory|Emergence}}
{{Intelligent Design}}

'''Irreducible complexity''' ('''IC''') is the argument that certain [[biological system]]s with multiple interacting parts would not function if one of the parts were removed, so supposedly could not have [[evolution|evolved]] by successive small modifications from earlier less complex systems through [[natural selection]], which would need all intermediate precursor systems to have been fully functional.<ref name="Behe 1996 p. 39" /> This negative argument is then complemented by the claim that the only alternative explanation is a "purposeful arrangement of parts" inferring design by an intelligent agent.<ref name="bio design classrooms" /> Irreducible complexity has become central to the [[creationism|creationist]] concept of [[intelligent design]] (ID), but the concept of irreducible complexity has been rejected by the [[scientific community]],<ref name="dover_behe_ruling">"We therefore find that Professor Behe's claim for irreducible complexity has been refuted in peer-reviewed research papers and has been rejected by the scientific community at large." [[s:Kitzmiller v. Dover Area School District#E. Application of the Endorsement Test to the ID Policy|4:Whether ID Is Science, in E. Application of the Endorsement Test to the ID Policy, Ruling, Judge John E. Jones III, ''Kitzmiller v. Dover Area School District'']]</ref> which regards intelligent design as [[pseudoscience]].<ref>"True in this latest creationist variant, advocates of so-called intelligent design ... use more slick, pseudoscientific language. They talk about things like "irreducible complexity" {{cite book |author= Shulman, Seth |title= Undermining science: suppression and distortion in the Bush Administration |publisher= University of California Press |location= Berkeley |year= 2006 |page= [https://archive.org/details/underminingscien00shul/page/13 13] |isbn= 978-0-520-24702-4 |url= https://archive.org/details/underminingscien00shul/page/13 }} "for most members of the mainstream scientific community, ID is not a scientific theory, but a creationist pseudoscience."<br />{{cite journal |first= David |last= Mu |title= Trojan Horse or Legitimate Science: Deconstructing the Debate over Intelligent Design |journal= Harvard Science Review |volume= 19 |issue= 1 |date= Fall 2005 |url= http://www.hcs.harvard.edu/~hsr/fall2005/mu.pdf |url-status= dead |archive-url= https://web.archive.org/web/20070724203349/http://www.hcs.harvard.edu/~hsr/fall2005/mu.pdf |archive-date= 2007-07-24 }}<br />{{cite journal |author= Perakh, M |title= Why Intelligent Design Isn't Intelligent — Review of: Unintelligent Design |journal= Cell Biol. Educ. |volume= 4 |issue= 2 |pages= 121–2 |date= Summer 2005 |doi= 10.1187/cbe.05-02-0071 |pmc= 1103713}}<br />Mark D. Decker. College of Biological Sciences, General Biology Program, University of Minnesota {{usurped|1=[https://web.archive.org/web/20100930160317/http://www.texscience.org/files/faqs.htm Frequently Asked Questions About the Texas Science Textbook Adoption Controversy]}} "The Discovery Institute and ID proponents have a number of goals that they hope to achieve using disingenuous and mendacious methods of marketing, publicity, and political persuasion. They do not practice real science because that takes too long, but mainly because this method requires that one have actual evidence and logical reasons for one's conclusions, and the ID proponents just don't have those. If they had such resources, they would use them, and not the disreputable methods they actually use."<br />See also [[list of scientific societies explicitly rejecting intelligent design]]</ref> Irreducible complexity and [[specified complexity]], are the two main arguments used by intelligent-design proponents to support their version of the theological [[teleological argument|argument from design]].<ref name="bio design classrooms" /><ref name="LiveScience- msnbc.com">{{cite web |url= https://www.nbcnews.com/id/wbna9452500 |title= Why scientists dismiss 'intelligent design' – LiveScience |first= Ker |last= Than |date= September 23, 2005 |publisher= [[NBC News]] |access-date= 2010-05-17 }}</ref>

The central concept, that complex biological systems which require all their parts to function could not evolve by the incremental changes of natural selection so must have been produced by an intelligence, was already featured in [[creation science]].<ref name="Scott 2009 p. 126">{{harvnb| Scott | 2009 | pp=[https://books.google.com/books?id=FAAlDQAAQBAJ&pg=PA126 123, 126]}} "The biochemist Michael Behe contends that intelligence is required to produce irreducibly complex cellular structures (ones that couldn't function if a single part were removed) because such structures could not have been produced by the incremental additions of natural selection (Behe 1996).  ... More important than whether irreducibly complex structures actually occur other than by definition, however, is the critical question of whether they can be produced by natural mechanisms. Behe answers no, claiming that natural selection, the main mechanism of evolutionary change, is inadequate to the task. He views natural selection as assembling a complex structure by stringing together components one at a time, with each addition requiring a selective advantage. .... Behe's idea of irreducible complexity was anticipated in creation science; much as in Paley's conception, creation science proponents hold that structures too complex to have occurred 'by chance' require special creation."</ref><ref name="Slack 2008 p. 173" /> The 1989 school textbook ''[[Of Pandas and People]]'' introduced the alternative terminology of ''intelligent design'', a revised section in the 1993 edition of the textbook argued that a blood-clotting system demonstrated this concept.<ref>{{cite book |last=William |first=Davis |title=OF PANDAS AND PEOPLE - The Central Question of Biological Origins |publisher=Haughton Publishing Company |year=1993 |isbn=0914513400 |chapter=Excursion Chapter 6 - Biochemical Similarities}}, p. 145; "<i>In fact, having a primitive, poorly controlled clotting system would probably be more dangerous to an animal, and therefore less advantageous, than no having no such system at all!</i> Thus the clotting system cannot have emerged piecemeal.  Like a car or a sentence, it requires the cooperative interaction of pre-existing components to work."</ref><ref name="flare-up 2006" />

This section was written by [[Michael Behe]], a professor of biochemistry at [[Lehigh University]]. He subsequently introduced the expression ''irreducible complexity'' along with a full account of his arguments, in his 1996 book ''[[Darwin's Black Box]]'', and said it made evolution through natural selection of random mutations impossible, or extremely improbable.<ref name="bio design classrooms" /><ref name="Behe 1996 p. 39">{{cite book | last=Behe | first=M.J. | title=Darwin's Black Box: The Biochemical Challenge to Evolution | publisher=Free Press | series=Touchstone book | year=2006| isbn=978-0-684-82754-4 | url=https://books.google.com/books?id=7L8mkq4jG6EC&pg=PA39 | access-date=16 July 2023 | page=39|quote=By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning. An irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional. An irreducibly complex biological system, if there is such a thing, would be a powerful challenge to Darwinian evolution. Since natural selection can only choose systems that are already working, then if a biological system cannot be produced gradually it would have to arise as an integrated unit, in one fell swoop, for natural selection to have anything to act on.|edition=2}} (originally published 1996).</ref> This was based on the mistaken assumption that evolution relies on improvement of existing functions, ignoring how complex adaptations originate from changes in function, and disregarding published research.<ref name="bio design classrooms" /> [[evolutionary biology|Evolutionary biologists]] have published rebuttals showing how systems discussed by Behe can evolve.<ref name="thornton2006" /><ref name="Redundant Complexity" />

In the 2005 ''[[Kitzmiller v. Dover Area School District]]'' trial, Behe gave testimony on the subject of irreducible complexity. The court found that "Professor Behe's claim for irreducible complexity has been refuted in peer-reviewed research papers and has been rejected by the scientific community at large."<ref name="dover_behe_ruling" />