Specified complexity: Difference between revisions

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{{Intelligent Design}}

'''Specified complexity''' is a creationist argument introduced by [[William Dembski]], used by advocates to promote the [[pseudoscience]] of [[intelligent design]].<ref name="Boudry 2010">{{cite journal |last1=Boudry |first1=Maarten |author-link1=Maarten Boudry |last2=Blancke |first2=Stefaan |last3=Braeckman |first3=Johan |author-link3=Johan Braeckman |date=December 2010 |title=Irreducible Incoherence and Intelligent Design: A Look into the Conceptual Toolbox of a Pseudoscience |journal=[[The Quarterly Review of Biology]] |volume=85 |issue=4 |pages=473–482 |doi=10.1086/656904 |pmid=21243965|url=https://biblio.ugent.be/publication/952482/file/6828579.pdf |hdl=1854/LU-952482 |s2cid=27218269 |hdl-access=free | issn=0033-5770 }} Article available from [https://biblio.ugent.be/publication/952482 Universiteit Gent]</ref> According to Dembski, the concept can formalize a property that singles out patterns that are both ''specified'' and ''complex'', where in Dembski's terminology, a ''specified'' pattern is one that admits short descriptions, whereas a ''complex'' pattern is one that is unlikely to occur by chance. An example cited by Dembski is a poker hand, where for example the repeated appearance of a [[royal flush (poker hand)|royal flush]] will raise suspicion of cheating.<ref>{{cite web | url=https://billdembski.com/intelligent-design/specified-complexity-made-simple/ | title=Specified Complexity Made Simple | date=26 February 2024 }}</ref> Proponents of intelligent design use specified complexity as one of their two main arguments, alongsidealong with [[irreducible complexity]].

Dembski argues that it is impossible for specified complexity to exist in patterns displayed by configurations formed by unguided processes. Therefore, Dembski argues, the fact that specified complex patterns can be found in living things indicates some kind of guidance in their formation, which is indicative of intelligence. Dembski further argues that one can show by applying [[No free lunch in search and optimization|no-free-lunch theorems]] the inability of evolutionary algorithms to select or generate configurations of high specified complexity. Dembski states that specified complexity is a reliable marker of design by an [[intelligent designer|intelligent agent]]—a central tenet to intelligent design, which Dembski argues for in opposition to [[evolution|modern evolutionary theory]]. Specified complexity is what Dembski terms an "explanatory filter": one can recognize design by detecting '''complex specified information''' ('''CSI'''). Dembski argues that the unguided emergence of CSI solely according to known [[physical laws]] and chance is highly improbable.<ref>Olofsson, P., "Intelligent design and mathematical statistics: a troubled alliance", ''Biology and Philosophy'', (2008) 23: 545. {{doi|10.1007/s10539-007-9078-6}} ([https://web.archive.org/web/20180120070714/https://pdfs.semanticscholar.org/8def/d6c4582d252e55d8b4a188ccdb9bff6453c3.pdf pdf], retrieved December 18, 2017)</ref>

The concept of specified complexity is widely regarded as mathematically unsound and has not been the basis for further independent work in [[information theory]], in the theory of [[complex systems]], or in [[biology]].<ref>{{cite web |url=http://www.talkorigins.org/faqs/information/dembski.html |title=Information Theory and Creationism: William Dembski |author=Rich Baldwin |year=2005 |publisher=[[TalkOrigins Archive]] |access-date=2010-05-10}}</ref><ref>Mark Perakh, (2005). ''[http://www.talkreason.org/articles/newmath.cfm Dembski "displaces Darwinism" mathematically -- or does he?]''</ref><ref>Jason Rosenhouse, (2001). ''[http://educ.jmu.edu/~rosenhjd/sewell.pdf How Anti-Evolutionists Abuse Mathematics]'' The Mathematical Intelligencer, Vol. 23, No. 4, Fall 2001, pp. 3–8.</ref> A study by [[Wesley R. Elsberry|Wesley Elsberry]] and [[Jeffrey Shallit]] states: "Dembski's work is riddled with inconsistencies, equivocation, flawed use of mathematics, poor scholarship, and misrepresentation of others' results."<ref>{{cite web|url=http://www.talkreason.org/articles/eandsdembski.pdf|last1=Elsberry|first1=Wesley|last2=Shallit|first2=Jeffrey|year=2003|title=Information Theory, Evolutionary Computation, and Dembski's 'Complex Specified Information|access-date=20 October 2017}}</ref> Another objection concerns Dembski's calculation of probabilities. According to [[Martin Nowak]], a Harvard professor of mathematics and evolutionary biology, "We cannot calculate the probability that an eye came about. We don't have the information to make the calculation."<ref name="time.comTime">

Wallis, Claudia (2005). [http://content.time.com/time/magazine/article/0,9171,1090909,00.html Time Magazine], printed 15 August 2005, page 32

</ref>

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</blockquote>

Dembski notes that the term "Law of Conservation of Information" was previously used by [[Peter Medawar]] in his book <cite>The Limits of Science</cite> (1984) "to describe the weaker claim that deterministic laws cannot produce novel information."<ref>[http://www.designinference.com/documents/2005.03.Searching_Large_Spaces.pdf "Searching Large Spaces: Displacement and the No Free Lunch Regress (356k PDF)] {{Webarchive|url=https://web.archive.org/web/20150104032640/http://www.designinference.com/documents/2005.03.Searching_Large_Spaces.pdf |date=2015-01-04 }}", pp. 15-16, describing an argument made by [[Michael Shermer]] in ''How We Believe: Science, Skepticism, and the Search for God'', 2nd ed. (2003).</ref> The actual validity and utility of Dembski's proposed law are uncertain; it is neither widely used by the scientific community nor cited in mainstream scientific literature. A 2002 essay by Erik Tellgren provided a mathematical rebuttal of Dembski's law and concludes that it is "mathematically unsubstantiated."<ref>[http://www.talkreason.org/articles/dembski_LCI.pdf On Dembski's law of conservation of information] Erik Tellgren. talkreason.org, 2002. (PDF file)</ref>

==Specificity==

In a more recent paper,<ref>William A. Dembski (2005). [http://www.designinference.com/documents/2005.06.Specification.pdf ''Specification: The Pattern that Signifies intelligence''] {{Webarchive|url=https://web.archive.org/web/20070728121523/http://www.designinference.com/documents/2005.06.Specification.pdf |date=2007-07-28 }}</ref> Dembski provides an account which he claims is simpler and adheres more closely to the theory of [[statistical hypothesis testing]] as formulated by [[Ronald Fisher]]. In general terms, Dembski proposes to view design inference as a statistical test to reject a chance hypothesis P on a space of outcomes Ω.

Dembski's proposed test is based on the [[Kolmogorov complexity]] of a pattern ''T'' that is exhibited by an event ''E'' that has occurred. Mathematically, ''E'' is a subset of Ω, the pattern ''T'' specifies a set of outcomes in Ω and ''E'' is a subset of ''T''. Quoting Dembski<ref>(loc. cit. p. 16)</ref>

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Kolmogorov complexity provides a measure of the computational resources needed to specify a pattern (such as a DNA sequence or a sequence of alphabetic characters).<ref>Michael Sipser (1997). ''Introduction to the Theory of Computation'', PWS Publishing Company.</ref> Given a pattern ''T'', the number of other patterns may have Kolmogorov complexity no larger than that of ''T'' is denoted by φ(''T''). The number φ(''T'') thus provides a ranking of patterns from the simplest to the most complex. For example, for a pattern ''T'' which describes the bacterial [[flagellum]], Dembski claims to obtain the upper bound φ(''T'') ≤ 10²⁰.

Dembski defines '''specified complexity''' of the pattern ''T'' under the chance hypothesis P as

:<math> \sigma= - \log_2 [R \times \varphi(T) \times \operatorname{P}(T)], </math>

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| title = On Dembski's Law Of Conservation Of Information

| date = June 30, 2002

| author = Erik Tellgren}}</ref> Dembski responded in part that he is not "in the business of offering a strict [[mathematical proof]] for the inability of material mechanisms to generate specified complexity".<ref>William A. Dembski, (Aug 2002). [http://www.designinference.com/documents/2002.08.Erik_Response.htm ''If Only Darwinists Scrutinized Their Own Work as Closely: A Response to "Erik"''] {{Webarchive|url=https://web.archive.org/web/20130226010345/http://designinference.com/documents/2002.08.Erik_Response.htm |date=2013-02-26 }}.</ref> [[Jeffrey Shallit]] states that Demski's mathematical argument has multiple problems, for example; a crucial calculation on page 297 of ''No Free Lunch'' is off by a factor of approximately 10⁶⁵.<ref name=shallit>[[Jeffrey Shallit]] (2002) [http://www.cs.uwaterloo.ca/~shallit/nflr3.txt A review of Dembski's ''No Free Lunch'']</ref>

Dembski's calculations show how a simple [[smooth function]] cannot gain information. He therefore concludes that there must be a designer to obtain CSI. However, natural selection has a branching mapping from one to many (replication) followed by pruning mapping of the many back down to a few (selection). When information is replicated, some copies can be differently modified while others remain the same, allowing information to increase. These increasing and reductional mappings were not modeled by Dembski. In other words, Dembski's calculations do not model birth and death. This basic flaw in his modeling renders all of Dembski's subsequent calculations and reasoning in ''No Free Lunch'' irrelevant because his basic model does not reflect reality. Since the basis of ''No Free Lunch'' relies on this flawed argument, the entire thesis of the book collapses.<ref>Thomas D. Schneider. (2002) [http://www.lecb.ncifcrf.gov/~toms/paper/ev/dembski/specified.complexity.html Dissecting Dembski's "Complex Specified Information"] {{webarchive|url=https://web.archive.org/web/20051026135240/http://www.lecb.ncifcrf.gov/~toms/paper/ev/dembski/specified.complexity.html |date=2005-10-26 }}</ref>

According to Martin Nowak, a Harvard professor of mathematics and evolutionary biology "We cannot calculate the probability that an eye came about. We don't have the information to make the calculation".<ref name="time.comTime"/>

Dembski's critics note that specified complexity, as originally defined by Leslie Orgel, is precisely what Darwinian evolution is supposed to create. Critics maintain that Dembski uses "complex" as most people would use "absurdly improbable". They also claim that his argument is [[circular reasoning|circular]]: CSI cannot occur naturally because Dembski has defined it thus. They argue that to successfully demonstrate the existence of CSI, it would be necessary to show that some biological feature undoubtedly has an extremely low probability of occurring by any natural means whatsoever, something which Dembski and others have almost never attempted to do. Such calculations depend on the accurate assessment of numerous contributing probabilities, the determination of which is often necessarily subjective. Hence, CSI can at most provide a "very high probability", but not absolute certainty.

Another criticism refers to the problem of "arbitrary but specific outcomes". For example, if a coin is tossed randomly 1000 times, the probability of any particular outcome occurring is roughly one in 10³⁰⁰. For any particular specific outcome of the coin-tossing process, the ''a priori'' probability (probability measured before event happens) that this pattern occurred is thus one in 10³⁰⁰, which is astronomically smaller than Dembski's universal probability bound of one in 10¹⁵⁰. Yet we know that the ''post hoc'' probability (probabilitlyprobability as observed after event occurs) of its happening is exactly one, since we observed it happening. This is similar to the observation that it is unlikely that any given person will win a lottery, but, eventually, a lottery will have a winner; to argue that it is very unlikely that any one player would win is not the same as proving that there is the same chance that no one will win. Similarly, it has been argued that "a space of possibilities is merely being explored, and we, as pattern-seeking animals, are merely imposing patterns, and therefore targets, after the fact."<ref name="arn.org"/>

Apart from such theoretical considerations, critics cite reports of evidence of the kind of evolutionary "spontanteous generation" that Dembski claims is too improbable to occur naturally. For example, in 1982, B.G. Hall published research demonstrating that after removing a gene that allows sugar digestion in certain bacteria, those bacteria, when grown in media rich in sugar, rapidly evolve new sugar-digesting enzymes to replace those removed.<ref>B.G. Hall (1982). "Evolution of a regulated operon in the laboratory", ''[[Genetics (journal)|Genetics]]'', 101(3-4):335-44. [https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=6816666&query_hl=1 In PubMed.]</ref> Another widely cited example is the discovery of [[nylon eating bacteria]] that produce enzymes only useful for digesting synthetic materials that did not exist prior to the invention of [[nylon]] in 1935.

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* [http://www.talkorigins.org/faqs/information/dembski.html Information Theory and Creationism William Dembski] by Rich Baldwin, from Information Theory and Creationism, compiled by Ian Musgrave and Rich Baldwin

* [http://www.bostonreview.net/BR27.3/orr.html Critique of ''No Free Lunch'' by H. Allen Orr] from the Boston Review

* [https://schneider.ncifcrf.gov/paper/ev/dembski/specified.complexity.html Dissecting Dembski's "Complex Specified Information"] {{Webarchive|url=https://web.archive.org/web/20170317075913/https://schneider.ncifcrf.gov/paper/ev/dembski/specified.complexity.html |date=2017-03-17 }} by Thomas D. Schneider.

* [http://www.talkreason.org/articles/jello.cfm William Dembski's treatment of the No Free Lunch theorems is written in jello] by No Free Lunch theorems co-founder, [[David Wolpert]]

* [httphttps://evolutionlist.blogspot.com/2006/05/genetic-id-and-explanatory-filter.html The Evolution List - Genetic ID and the Explanatory Filter] by Allen MacNeill.

* [http://www.designinference.com/ Design Inference Website] - The writing of William A. Dembski

* [https://web.archive.org/web/20080313093300/http://csicop.org/sb/2000-12/reality-check.html Committee for Skeptical Inquiry - Reality Check, The Emperor's New Designer Clothes] - [[Victor J. Stenger]]