Difference between revisions of "Reductionism" - New World Encyclopedia

From New World Encyclopedia
Line 8: Line 8:
  
 
==Varieties of reductionism==
 
==Varieties of reductionism==
−
There are several generally accepted types or forms of reduction in both science and philosophy:
+
Most reductionist claims in philosophy can be put in one of two categories, which are sometimes called ontological reductionism and theoretical reductionism.
  
 
===Ontological reductionism===
 
===Ontological reductionism===
−
{{main|Ontological reductionism}}
+
Some claims about reductionism concern things in the world, such as objects, properties, and events.  These claims state that one thing or set of things can be reduced to some other, more basic thing or set of things. Consider a particular example:
−
Is the idea that everything that exists is made from a small number of basic substances that behave in regular ways (''compare to [[monism]]''). There are two forms of ontological reductionism: token ontological reductionism, and type ontological reductionism.  [[Token ontological reductionism]] is the idea that every item that exists is a sum item. For perceivable items, it says that every perceivable item is a sum of items at a smaller level of complexity.  [[Type ontological reductionism]] is the idea that every type of item is a sum (of typically less complex) type(s) of item(s). For perceivable types of item, it says that every perceivable type of item is a sum of types of items at a lower level of complexity. Token ontological reduction of biological things to chemical things is generally accepted. Type ontological reduction of biological things to chemical things is often rejected.
 
  
−
===Methodological reductionism===
+
<blockquote>The population of Springfield is nothing more than Adam, Alex, Alice, Anna...</blockquote>
−
{{main|Methodological reductionism}}
 
−
Is the idea that developing an understanding of a complex system's constituent parts (and their interactions) is the best way to develop an understanding of the system as a whole.<ref name = "Stanford">[http://plato.stanford.edu/entries/physics-holism/  Phisics Holism], Stanford University.</ref>
 
  
−
===Methodological individualism===
+
In this claim, a thing (the population of Springfield) is reduced to a set of individual people.  The idea is that that set of people is all there is to 'the population', and everything that's true about the latter comes down to something that's true about the former.  For example, if it's true that the population is shrinking, this might be explained by saying that Adam and Alex left town.
−
{{main|Methodological individualism}}
 
−
Protends [[sociology|sociological]] inquiry based on individual decisions.
 
  
−
===Theoretical reductionism===
+
Note that there's an asymmetry in the relation between those two facts: if Adam and Alex leave town (and everyone else stays put), then it's necessarily true that the population of Springfield shrinks.  But if the population of Springfield shrinks, it's not necessarily true that Adam and Alex left; it might instead be the case that Alice and Anna left.  This asymmetry is indicative of the fact that the set of people is more 'basic' than the population.  So the reductionist claim doesn't merely state that there's some close relation between the two, it further claims that one is more fundamental.  You can understand everything about the population by understanding what's going on with Adam, Alex, Alice, Anna etc., but not the other way around.
−
Has two definitions. In the first definition it is  the idea that the terms of a theory of science A referring to objects at a higher level of complexity than the objects of science B can be replaced by the terms of science B.  In the second definition of [[theoretical reductionism]] the older theories or explanations are not generally replaced outright by new ones, but new theories are refinements or reductions of the old theory into more efficacious forms with greater detail and explanatory power. The older theories are supposedly ''absorbed'' into the newer ones and they can be deductively derived from the latter.
 
  
−
===Scientific reductionism===
+
One subtle issue about ontological reductionism is whether one 'reduces away' the thing or things in question. In the above example, it intuitively seems that even though the population reduces to the set of people, the population still exists. But consider a different example:
−
{{main|Scientific reductionism}}
 
−
Has been used to describe all of the above ideas as they relate to science, but is most often used to describe the idea that all phenomena can be reduced by scientific explanations. It is useful to note in addition that there are no explicit theories that reject token ontological reduction of biological items to chemical items, or that reject token ontological reduction of chemical items to physics items. Also by the middle of the 20th century the empirical results made extremely implausible the view that there are fundamental forces activated only by highly complex configurations of subatomic particles.
 
  
−
===Set-Theoretic Reductionism===
+
<blockquote>Santa Claus is nothing more than a story told to children.</blockquote>
−
Is the idea that all of mathematics can be reduced to set theory.  Throughout the history of mathematics, the idea that all  of mathematics can be reduced to a single branch has been very powerful.  However, most of the attempts to reduce mathematics to a single branch have been proven either incomplete or inconsistent.  Most of these proofs were developed by [[Gottlob Frege]].  He then proposed his own form of reductionism, [[logicism]], which in turn was famously disproven by [[Russell's Paradox]].  Many believe that [[Godel's Incompleteness Theorem]] proves that reductionism in mathematics is impossible (since all systems cannot be both complete and consistent at the same time), but there is still a great deal of debate on the matter.
 
  
−
===Linguistic reductionism===
+
As before, everything that's true about Santa Claus comes down to something true about the story.  If it's true that Santa Claus lives on the North Pole, that's just because that's part of the story.  But in this case, the fact that Santa Claus is reduced to a story seems to mean that Santa does not exist. Putting the matter metaphorically, he has been reduced away.
−
Is the idea that everything can be described in a language with a limited number of core concepts, and combinations of those concepts. (See [[Basic English]] and the constructed language [[Toki Pona language|Toki Pona]]).
 
  
−
===Greedy reductionism===
+
===Theoretical reductionism===
−
{{main|Greedy reductionism}}
+
A distinct but related type of reduction can hold between ''theories'' - where 'theories' are understood as sets of claims. For example, it is often claimed (though not without controversy) that biology will ultimately be reduced to chemistry, and chemistry in turn will be reduced to physics. There are two dominant models of how this is supposed to work, one expounded by Ernest Nagel and the other by John Kemeny and Paul Oppenheim.
−
Is a term coined by [[Daniel Dennett]] to condemn those forms of reductionism that try to explain too much with too little.
 
−
 
 
−
===Eliminativism===
 
−
{{main|Eliminativism}}
 
−
Is sometimes regarded as a form of reductionism. [[Eliminativism]] is the idea that some objects referred to in a given theory do not exist. Accordingly, the terms of that theory are abandoned or eliminated.  [[Eliminativism]] is often regarded as a form of reductionism, since the eliminated theory is at some point replaced by a theory referring to the objects that were not eliminated. For example, the theory that some diseases are caused by occupation by a demon has been eliminated. Accordingly it has been reduced by elimination to other theories about the causes of diseases. 
 
  
−
Other typologies are also possible.  For example, Richard Jones in a systematic study of reductionism in philosophy, the natural sciences, the social sciences and religion differentiates five types: substantive, structural (causal), theoretical, conceptual (descriptive), and methodological.  He critiicizes reductionism and advocates the importance of emergence.  John Dupre also advocates antireductionism.
+
====The Nagel Model====
  
−
The denial of reductionist ideas is [[holism]] or [[emergence|emergentism]]: the idea that things can have properties as a whole that are not explainable from the sum of their parts. The principle of holism was concisely summarized by Aristotle in the Metaphysics: "The whole is more than the sum of its parts". Phenomena such as [[emergence]] and work within the field of [[complex systems]] theory are also considered to bring forth possible [[objection]]s to some forms of reductionism. It's worth noticing that they don't object to token ontological reduction of biology to chemistry, nor to token ontological reduction of chemistry to physics. They would only be possible objections to other forms of reduction.
 
  
−
Outside the field of strictly philosophical discourse and outside the fields of biology, chemistry and physics, the best known denial of reductionisms of whatever kind is [[religion|religious belief]], which, in most of its forms, assigns supernatural original causes to phenomena.  In this approach, even if a given system operates by strictly reductionistic causes-and-effects, its "true" genesis and placement within larger (and typically unknown) systems is bound up with an intelligence or "consciousness" beyond normal human perception. It is worth asking how religious systems regard token biological reduction of biological items to chemical items and chemical items to physics items.
+
====The Kemeny-Oppenheim Model====
  
 
== History ==
 
== History ==
Line 61: Line 45:
  
 
==References==
 
==References==
−
*Dawkins, R. (1976) ''The Selfish Gene''. Oxford University Press; 2nd edition, December 1989 ISBN 0-19-217773-7.
+
*Churchland, P.S. (1986) ''Neurophilosophy'', Cambridge, MA: MIT Press.  
−
*Descartes (1637) Discourses Part V
+
*Kemeny, J. and Oppenheim, P. (1956) ‘On Reduction’, ''Philosophical Studies'' 7: 6–18.
−
*Dupre, J. (1993) ''The Disorder of Things''. Harvard University Press.
+
*Kim, J. (1998) 'Reduction, Problems of'. In E. Craig (Ed.), ''Routledge Encyclopedia of Philosophy.'' London: Routledge
−
*Jones, R. (2000) ''Reductionism: Analysis and the Fullness of Reality''. Bucknell University Press.
+
*Nagel, E. (1961) ''The Structure of Science''. New York: Harcourt Press.
−
*Nagel, E. (1961) ''The Structure of Science''. New York.
 
−
*Ruse, M. (1988) ''Philosophy of Biology''. Albany, NY.
 
−
*Dennett, Daniel. (1995) ''Darwin's Dangerous Idea''. Simon & Schuster. ISBN 0-684-82471-X.
 
−
* [[Alexander Rosenberg]] (2006) ''Darwinian Reductionism or How to Stop Worrying and Love Molecular Biology''. University of Chicago Press.
 
  
 
==External links==
 
==External links==

Revision as of 00:57, 24 August 2007

Descartes held that non-human animals could be reductively explained as automata — De homines 1622.

In philosophy, reductionism is a theory that asserts that the nature of complex things is reduced to the nature of sums of simpler or more fundamental things. This can be said of objects, phenomena, explanations, theories, and meanings.

Reductionism is often understood to imply the unity of science. For example, fundamental chemistry is based on physics, fundamental biology and geology are based on chemistry, psychology is based on biology, sociology is based on psychology, and political science, anthropology, and even economics are based on sociology. The first two of these reductions are commonly accepted but the last three or four — psychology to biology and so on — are controversial. For example, aspects of evolutionary psychology and sociobiology are rejected by those who claim that complex systems are inherently irreducible or holistic. Some strong reductionists believe that the behavioral sciences should become "genuine" scientific disciplines by being based on genetic biology, and on the systematic study of culture (cf. Dawkins's concept of memes).

In his book The Blind Watchmaker, Richard Dawkins introduced the term "hierarchical reductionism" (p. 13) to describe the view that complex systems can be described with a hierarchy of organizations, each of which can only be described in terms of objects one level down in the hierarchy. He provides the example of a computer, which under hierarchical reductionism can be explained well in terms of the operation of hard drives, processors, and memory, but not on the level of AND or NOR gates, or on the even lower level of electrons in a semiconductor medium.

Varieties of reductionism

Most reductionist claims in philosophy can be put in one of two categories, which are sometimes called ontological reductionism and theoretical reductionism.

Ontological reductionism

Some claims about reductionism concern things in the world, such as objects, properties, and events. These claims state that one thing or set of things can be reduced to some other, more basic thing or set of things. Consider a particular example:

The population of Springfield is nothing more than Adam, Alex, Alice, Anna...

In this claim, a thing (the population of Springfield) is reduced to a set of individual people. The idea is that that set of people is all there is to 'the population', and everything that's true about the latter comes down to something that's true about the former. For example, if it's true that the population is shrinking, this might be explained by saying that Adam and Alex left town.

Note that there's an asymmetry in the relation between those two facts: if Adam and Alex leave town (and everyone else stays put), then it's necessarily true that the population of Springfield shrinks. But if the population of Springfield shrinks, it's not necessarily true that Adam and Alex left; it might instead be the case that Alice and Anna left. This asymmetry is indicative of the fact that the set of people is more 'basic' than the population. So the reductionist claim doesn't merely state that there's some close relation between the two, it further claims that one is more fundamental. You can understand everything about the population by understanding what's going on with Adam, Alex, Alice, Anna etc., but not the other way around.

One subtle issue about ontological reductionism is whether one 'reduces away' the thing or things in question. In the above example, it intuitively seems that even though the population reduces to the set of people, the population still exists. But consider a different example:

Santa Claus is nothing more than a story told to children.

As before, everything that's true about Santa Claus comes down to something true about the story. If it's true that Santa Claus lives on the North Pole, that's just because that's part of the story. But in this case, the fact that Santa Claus is reduced to a story seems to mean that Santa does not exist. Putting the matter metaphorically, he has been reduced away.

Theoretical reductionism

A distinct but related type of reduction can hold between theories - where 'theories' are understood as sets of claims. For example, it is often claimed (though not without controversy) that biology will ultimately be reduced to chemistry, and chemistry in turn will be reduced to physics. There are two dominant models of how this is supposed to work, one expounded by Ernest Nagel and the other by John Kemeny and Paul Oppenheim.

The Nagel Model

The Kemeny-Oppenheim Model

History

The idea of reductionism was introduced by Descartes in Part V of his Discourses (1637). Descartes argued the world was like a machine, its pieces like clockwork mechanisms, and that the machine could be understood by taking its pieces apart, studying them, and then putting them back together to see the larger picture. Descartes was a full mechanist, but only because he did not accept the conservation of direction of motions of small things in a machine, including an organic machine. Newton's theory required such conservation for inorganic things at least. When such conservation was accepted for organisms as well as inorganic objects by the middle of the 20th century, no organic mechanism could easily, if at all, be a Cartesian mechanism.

See also

References
ISBN links support NWE through referral fees

  • Churchland, P.S. (1986) Neurophilosophy, Cambridge, MA: MIT Press.
  • Kemeny, J. and Oppenheim, P. (1956) ‘On Reduction’, Philosophical Studies 7: 6–18.
  • Kim, J. (1998) 'Reduction, Problems of'. In E. Craig (Ed.), Routledge Encyclopedia of Philosophy. London: Routledge
  • Nagel, E. (1961) The Structure of Science. New York: Harcourt Press.

External links

Credits

New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

The history of this article since it was imported to New World Encyclopedia:

Note: Some restrictions may apply to use of individual images which are separately licensed.

Retrieved from https://www.newworldencyclopedia.org/p/index.php?title=Reductionism&oldid=424395

Content is available under Creative Commons Attribution/Share-Alike License; additional terms may apply. See Terms of Use for details.
Copyright Logo
Powered by MediaWiki