Reductionism

{{bronze}}[[Image:Duck_of_Vaucanson.jpg|right|thumb|165px|Reductionism in practice: a duck is the sum of a bunch of gears and a big hose.]]
{{philosophy}}

'''Reductionism''' is the [[philosophy|philosophical]] position that a complex phenomenon can be described ultimately by the component pieces that make up that phenomenon. Reductionism can be applied to almost anything, whether it is a physical system, a process, a thought, or a living creature.  Many argue that the [[scientific method]] relies heavily on reductionism, and [[science]]'s ability to accurately model [[reality]] is linked to how much it can be reduced. Others have argued that certain systems demonstrate [[emergence|emergent properties]] that are above and beyond the component pieces of the system. Many attempts are being developed to figure out a way to test for the existence of and ultimately rigorously study these kinds of phenomena.

==Ontological vs. methodological reductionism==
Two forms of reductionism are often contrasted. Methodological reductionism refers to the use of a methodology that seeks to describe or explain a phenomenon in terms of its constituent pieces. Ontological reductionism makes the stronger, [[metaphysical]] claim that the phenomenon itself doesn't exist, but only its constituent parts do. This is sometimes referred to as "eliminativism".

==Unification of science by means of reductionism==
{{cquote|[[Math]] is really [[logic]]. Logic is really philosophy. Philosophy is really [[psychology]]. Psychology is really [[biology]]. Biology is really [[Chemistry]]. Chemistry is really [[physics]]. Physics is really math.|||Ben Mordecai<ref>[https://www.quora.com/Humor/Whats-a-good-ending-for-Biology-is-really-chemistry-Chemistry-is-really-physics-Physics-is-really-math-Math-is-really-hard#answer_1638266 What's a good ending for 'Biology is really chemistry. Chemistry is really physics. Physics is really math. Math is really hard'?] - Quora</ref>}}

Various schemes to subsume what are sometimes known as the "special sciences" into a "fundamental" or "general science" have been proposed throughout the history of science. The search for a "[[theory of everything]]" has been construed by some as a potential discovery that would unify and reduce all science to [[physics]]. This is pithily summed up by Ernest Rutherford's quip that "All science is either physics or stamp collecting."<ref>[http://www.americanscientist.org/issues/pub/undisciplined-science Undisciplined Science], Brian Hayes, ''American Scientist''</ref> This position is often ascribed to the "unity of science" movement associated with [[logical positivism]], though not all the scientists and philosophers in this tradition held to a strict version of it.<ref>See [http://plato.stanford.edu/entries/scientific-unity/ The Unity of Science] in the SEP</ref> Others have advocated collapsing the [[social science]]s and humanities into [[biology]], using [[evolution]] as unifying theory. (Or sometimes, the weaker claim that all the special sciences should be done using an evolutionary or biological approach.) This notion was popularized by [[Edward O. Wilson]] in his book ''Consilience: The Unity of Knowledge''.<ref>{{wpa|Consilience (book)|''Consilience''}}</ref> In ''Darwin's Dangerous Idea'', [[Daniel Dennett]] used evolution as a unifying theory but takes a different approach by re-conceptualizing [[natural selection]] as an algorithmic process that can be applied to all fields of knowledge.<ref>{{wpa|Darwin's Dangerous Idea|''Darwin's Dangerous Idea''}}</ref>

==Arguments against reductionism==
Due to the success of reductionist programs in science, it has often been taken that (by [[induction]]) all scientifically-oriented research ought to be reductionist in nature. A number of arguments have been made against this line of thinking, proposing methodologies from ones that fully integrate reductionism but constrain its applicability to some degree to ones that reject reductionism entirely.

The majority of states of matter in [[quantum theory]] have holistic features, but these can be analysed by studying correlations of repeated measurements on the components. Thus although the world actually is holistic, it's not so holistic that reductionist techniques cannot be applied.<ref>''Quantum Theory from First Principles: An Informational Approach'' by  Giacomo D'Ariano et al. (2017) Cambridge University Press. ISBN 9781107043428.</ref>

===Anti-reductionism and holism===
Anti-reductionist arguments are often associated with holism, although this is not necessarily the case. The term "holism" was originally coined by {{wpl|Jan Smuts}} to refer to the co-evolution between parts and wholes. He defined "wholism" as the concept that the whole is more than the sum of its parts.<ref>[http://djmarsay.wordpress.com/bibliography/science/smuts/smuts-holism-and-evolution/ Smuts' Holism and Evolution], Dave Marsay</ref> 

In [[philosophy of mind]], Jerry Fodor argued against reductionism (extending an argument made by Hilary Putnam) on the grounds of multiple realizability, i.e., that multiple physical kinds may underlie a single mental state.<ref>Jerry Fodor. [http://ethik.univie.ac.at/fileadmin/user_upload/inst_ethik_wiss_dialog/Fodor__J._1974._Special_sciences_in_Synhtese.pdf Special Sciences (Or: The Disunity of Science as a Working Hypothesis.] ''Synthese'', Vol. 28, No. 2 (Oct., 1974), pp. 97-115</ref><ref>See also SEP's entry for [http://plato.stanford.edu/entries/multiple-realizability/ Multiple Realizability]</ref> But Fodor has also argued against holism, claiming that it would make scientific [[psychology]] impossible because it would prevent any generalizations being made about mental states.<ref>Ernest Lepore and Jerry Fodor. [http://www.jstor.org/discover/10.2307/2108085?uid=3739832&uid=2129&uid=2&uid=70&uid=4&uid=3739256&sid=21100836942231 Precis of ''Holism: A Shopper's Guide''.] ''Philosophy and Phenomenological Research'' Vol. 53, No. 3 (Sep., 1993), pp. 637-640</ref> 

Another common angle from which to attack reductionism is to point out failed attempts to reduce certain special sciences. In biology, this usually involves arguing from the lack of a reductive account of evolution or [[genetics]] in terms of [[molecular biology]].<ref>See SEP's entry for [http://plato.stanford.edu/entries/reduction-biology/ Reductionism in Biology]</ref> In the behavioral and [[cognitive science|cognitive sciences]], the lack of a reductive account of the "hard problem" of [[consciousness]] is used as ammo for anti-reductionist arguments.<ref>See the IEP's entry for [http://www.iep.utm.edu/hard-con/ The Hard Problem of Consciousness.]</ref> (Though [[Daniel Dennett|some]] deny that the hard problem exists.)

===Anti-science rhetoric===
"Reductionism" is sometimes used as a [[snarl word|euphemism]] in [[anti-science]] [[rhetoric]]. For example, a common accusation from [[alternative medicine]] practitioners is that real doctors practice reductionism and refuse to consider the "whole". This is untrue; proper medical practice is to look at all possible disease vectors when diagnosing a patient, including the possibility of [[psychosomatic]] illness.<ref group=note>Some [[quack]]s use this to suggest that the "whole patient" is not treated because there is little or no personal interaction with the dreaded "[[allopathic]]" doctor. While the lack of personal interaction is an acknowledged problem of modern medical practice, it is a consequence of [[economics]] and logistical complexity, not of flawed methodology as quacks allege. Anti-reductionism here serves to [[Framing|frame]] legitimate practical problems as evidence of something more sinister; e.g., quacks claim scientists face these issues not because their solutions are complicated and they deal with a high number of patients, but because they're blinded by reductivist [[ideology]]. And, for good measure, quacks turn what is, in reality, evidence of their fraudulent practice into a virtue!</ref> Ironically, practitioners such as many [[chiropractic|chiropractors]] think one can ''reduce'' a diagnosis to the spine only. ([[Golden hammer|When one's only tool's a hammer…]])

Quite often, this comes down to a (sometimes cynical) failure to distinguish between ontological and methodological reductionism.

== See also ==
*[[Daniel Dennett#Dennettisms|Greedy reductionism]]
*[[Systems thinking]]
*[[Scientism]]
*[[Denis Noble]]

==External links==
*[http://www.iep.utm.edu/red-ism/ Reductionism], Internet Encyclopedia of Philosophy
*[http://onphilosophy.wordpress.com/2007/03/28/ Reduction], On Philosophy
*[http://www.drury.edu/ess/philsci/KleeCh5.html Reductionism, Anti-Reductionism, and Supervenience], Philosophy of Science notes, Drury University
*[[Thomas Nagel]]. [http://www.isnature.org/events/2009/Summer/r/Nagel1998-Rednism&AntiRednism.pdf Reductionism and Antireductionism.] ''The Limits of Reductionism in Biology'', 1998 Novartis Foundation symposium.

==Notes==
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==References==
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[[Category:Philosophy]]
[[Category:Philosophy of science]]

Categories: Philosophy, Philosophy of science