Reductionism is any of several related philosophical ideas regarding the associations between phenomena which can be described in terms of other simpler or more fundamental phenomena.
The Oxford Companion to Philosophy suggests that reductionism is "one of the most used and abused terms in the philosophical lexicon" and suggests a three part division:
Reductionism can be applied to any phenomenon, including objects, explanations, theories, and meanings.
For the sciences, application of methodological reductionism attempts explanation of entire systems in terms of their individual, constituent parts and their interactions. For example, the temperature of a gas is reduced to nothing beyond the average kinetic energy of its molecules in motion. Thomas Nagel speaks of 'psychophysical reductionism' (the attempted reduction of psychological phenomena to physics and chemistry), as do others and 'physico-chemical reductionism' (the attempted reduction of biology to physics and chemistry), again as do others.In a very simplified and sometimes contested form, such reductionism is said to imply that a system is nothing but the sum of its parts. However, a more nuanced opinion is that a system is composed entirely of its parts, but the system will have features that none of the parts have (which, in essence is the basis of emergentism). "The point of mechanistic explanations is usually showing how the higher level features arise from the parts."
Other definitions are used by other authors. For example, what John Polkinghorne terms 'conceptual' or 'epistemological' reductionismis the definition provided by Simon Blackburn and by Jaegwon Kim: that form of reductionism concerning a program of replacing the facts or entities entering statements claimed to be true in one type of discourse with other facts or entities from another type, thereby providing a relationship between them. Such an association is provided where the same idea can be expressed by "levels" of explanation, with higher levels reducible if need be to lower levels. This use of levels of understanding in part expresses our human limitations in remembering detail. However, "most philosophers would insist that our role in conceptualizing reality [our need for a hierarchy of "levels" of understanding] does not change the fact that different levels of organization in reality do have different 'properties'."
Reductionism should be distinguished from eliminationism: reductionists do not deny the existence of phenomena, but explain them in terms of another reality; eliminationists deny the existence of the phenomena themselves. For example, eliminationists deny the existence of life by their explanation in terms of physical and chemical processes.
Reductionism does not preclude the existence of what might be termed emergent phenomena, but it does imply the ability to understand those phenomena completely in terms of the processes from which they are composed. This reductionist understanding is very different from emergentism, which intends that what emerges in "emergence" is more than the sum of the processes from which it emerges.Some physicists, however, claim that reductionism and emergentism are complementary: both are needed to explain natural processes .
Most philosophers delineate three types of reductionism and anti-reductionism.
Ontological reductionism is the belief that reality is composed of a minimum number of kinds of entities or substances. This claim is usually metaphysical, and is most commonly a form of monism, in effect claiming that all objects, properties and events are reducible to a single substance. (A dualist who is an ontological reductionist would believe that everything is reducible to two substances—as one possible example, a dualist might claim that reality is composed of "matter" and "spirit".)
Richard Jones divides ontological reductionism into two: the reductionism of substances (e.g., the reduction of mind to matter) and the reduction of the number of structures operating in nature (e.g., the reduction of one physical force to another). This permits scientists and philosophers to affirm the former while being anti-reductionists regarding the latter.
Nancey Murphy has claimed that there are two species of ontological reductionism: one that claims that wholes are nothing more than their parts; and atomist reductionism, claiming that wholes are not "really real". She admits that the phrase "really real" is apparently senseless but she has tried to explicate the supposed difference between the two.
Ontological reductionism denies the idea of ontological emergence, and claims that emergence is an epistemological phenomenon that only exists through analysis or description of a system, and does not exist fundamentally.
Ontological reductionism takes two forms: 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 affirms that every perceivable item is a sum of items with a lesser degree of complexity. Token ontological reduction of biological things to chemical things is generally accepted.
Type ontological reductionism is the idea that every type of item is a sum type of item, and that every perceivable type of item is a sum of types of items with a lesser degree of complexity. Type ontological reduction of biological things to chemical things is often rejected.
Michael Ruse has criticized ontological reductionism as an improper argument against vitalism.
Methodological reductionism is the position that the best scientific strategy is to attempt to reduce explanations to the smallest possible entities. In a biological context, this means attempting to explain all biological phenomena in terms of their underlying biochemical and molecular processes.
Theory reduction is the process by which one theory absorbs another. For example, both Kepler's laws of the motion of the planets and Galileo's theories of motion formulated for terrestrial objects are reducible to Newtonian theories of mechanics because all the explanatory power of the former are contained within the latter. Furthermore, the reduction is considered beneficial because Newtonian mechanics is a more general theory—that is, it explains more events than Galileo's or Kepler's. Besides scientific theories, theory reduction more generally can be the process by which one explanation subsumes another.
This section needs additional citations for verification . (August 2011) (Learn how and when to remove this template message)
Reductionist thinking and methods form the basis for many of the well-developed topics of modern science, including much of physics, chemistry and cell biology. Classical mechanics in particular is seen as a reductionist framework, and statistical mechanics can be considered as a reconciliation of macroscopic thermodynamic laws with the reductionist method of explaining macroscopic properties in terms of microscopic components.
In science, reductionism implies that certain topics of study are based on areas that study smaller spatial scales or organizational units. While it is commonly accepted that the foundations of chemistry are based in physics, and molecular biology is based on chemistry, similar statements become controversial when one considers less rigorously defined intellectual pursuits. For example, claims that sociology is based on psychology, or that economics is based on sociology and psychology would be met with reservations. These claims are difficult to substantiate even though there are obvious associations between these topics (for instance, most would agree that psychology can affect and inform economics). The limit of reductionism's usefulness stems from emergent properties of complex systems, which are more common at certain levels of organization. For example, certain aspects of evolutionary psychology and sociobiology are rejected by some who claim that complex systems are inherently irreducible and that a holistic method is needed to understand them.
Some strong reductionists believe that the behavioral sciences should become "genuine" scientific disciplines based on genetic biology, and on the systematic study of culture (see Richard Dawkins's concept of memes). In his book The Blind Watchmaker , Dawkins introduced the term "hierarchical reductionism"to describe the opinion that complex systems can be described with a hierarchy of organizations, each of which is only described in terms of objects one level down in the hierarchy. He provides the example of a computer, which using hierarchical reductionism is explained in terms of the operation of hard drives, processors, and memory, but not on the level of logic gates, or on the even simpler level of electrons in a semiconductor medium.
Others argue that inappropriate use of reductionism limits our understanding of complex systems. In particular, ecologist Robert Ulanowicz says that science must develop techniques to study ways in which larger scales of organization influence smaller ones, and also ways in which feedback loops create structure at a given level, independently of details at a lower level of organization. He advocates (and uses) information theory as a framework to study propensities in natural systems.Ulanowicz attributes these criticisms of reductionism to the philosopher Karl Popper and biologist Robert Rosen.
Stuart Kauffman has argued that complex systems theory and phenomena such as emergence pose limits to reductionism.Emergence is especially relevant when systems exhibit historicity. Emergence is strongly related to nonlinearity. The limits of the application of reductionism are claimed to be especially evident at levels of organization with greater complexity, including living cells, neural networks, ecosystems, society, and other systems formed from assemblies of large numbers of diverse components linked by multiple feedback loops.
Nobel laureate Philip Warren Anderson used the idea that symmetry breaking is an example of an emergent phenomenon in his 1972 Science paper "More is different" to make an argument about the limitations of reductionism.One observation he made was that the sciences can be arranged roughly in a linear hierarchy—particle physics, solid state physics, chemistry, molecular biology, cellular biology, physiology, psychology, social sciences—in that the elementary entities of one science obeys the principles of the science that precedes it in the hierarchy; yet this does not imply that one science is just an applied version of the science that precedes it. He writes that "At each stage, entirely new laws, concepts and generalizations are necessary, requiring inspiration and creativity to just as great a degree as in the previous one. Psychology is not applied biology nor is biology applied chemistry."
Disciplines such as cybernetics and systems theory imply non-reductionism, sometimes to the extent of explaining phenomena at a given level of hierarchy in terms of phenomena at a higher level, in a sense, the opposite of reductionism.
In mathematics, reductionism can be interpreted as the philosophy that all mathematics can (or ought to) be based on a common foundation, which for modern mathematics is usually axiomatic set theory. Ernst Zermelo was one of the major advocates of such an opinion; he also developed much of axiomatic set theory. It has been argued that the generally accepted method of justifying mathematical axioms by their usefulness in common practice can potentially weaken Zermelo's reductionist claim.
Jouko Väänänen has argued for second-order logic as a foundation for mathematics instead of set theory,whereas others have argued for category theory as a foundation for certain aspects of mathematics.
The incompleteness theorems of Kurt Gödel, published in 1931, caused doubt about the attainability of an axiomatic foundation for all of mathematics. Any such foundation would have to include axioms powerful enough to describe the arithmetic of the natural numbers (a subset of all mathematics). Yet Gödel proved that for any self-consistent recursive axiomatic system powerful enough to describe the arithmetic of the natural numbers, there are propositions about the natural numbers that cannot be proved from the axioms but can be proved in the natural language with which we described the axioms. Such propositions are known as formally undecidable propositions. For example, the continuum hypothesis is undecidable in the Zermelo-Fraenkel set theory as shown by Cohen.
Religious reductionism generally attempts to explain religion by explaining it in terms of nonreligious causes. A few examples of reductionistic explanations for the presence of religion are: that religion can be reduced to humanity's conceptions of right and wrong, that religion is fundamentally a primitive attempt at controlling our environments, that religion is a way to explain the existence of a physical world, and that religion confers an enhanced survivability for members of a group and so is reinforced by natural selection.Anthropologists Edward Burnett Tylor and James George Frazer employed some religious reductionist arguments. Sigmund Freud held that religion is nothing more than an illusion, or even a mental illness, and Marx claimed that religion is "the sigh of the oppressed," and the opium of the people providing only "the illusory happiness of the people," thus providing two influential examples of reductionistic views against the idea of religion.
Linguistic reductionism is the idea that everything can be described or explained by a language with a limited number of concepts, and combinations of those concepts.An example is the language Toki Pona.
The concept of downward causation poses an alternative to reductionism within philosophy. This opinion is developed by Peter Bøgh Andersen, Claus Emmeche, Niels Ole Finnemann, and Peder Voetmann Christiansen, among others. These philosophers explore ways in which one can talk about phenomena at a larger-scale level of organization exerting causal influence on a smaller-scale level, and find that some, but not all proposed types of downward causation are compatible with science. In particular, they find that constraint is one way in which downward causation can operate.The notion of causality as constraint has also been explored as a way to shed light on scientific concepts such as self-organization, natural selection, adaptation, and control.
Philosophers of the Enlightenment worked to insulate human free will from reductionism. Descartes separated the material world of mechanical necessity from the world of mental free will. German philosophers introduced the concept of the "noumenal" realm that is not governed by the deterministic laws of "phenomenal" nature, where every event is completely determined by chains of causality.The most influential formulation was by Immanuel Kant, who distinguished between the causal deterministic framework the mind imposes on the world—the phenomenal realm—and the world as it exists for itself, the noumenal realm, which, as he believed, included free will. To insulate theology from reductionism, 19th century post-Enlightenment German theologians, especially Friedrich Schleiermacher and Albrecht Ritschl, used the Romantic method of basing religion on the human spirit, so that it is a person's feeling or sensibility about spiritual matters that comprises religion.
The anti-reductionist considers as minimum requirement upon the reductionist: "At the very least the anti-reductionist is owed an account of why the intuitions arise if they are not accurate."
A contrast to reductionism is holism or emergentism. Holism is the idea that items can have properties, (emergent properties), as a whole that are not explainable from the sum of their parts. The principle of holism was summarized concisely by Aristotle in the Metaphysics: "The whole is more than the sum of its parts".
The development of systems thinking has provided methods that seek to describe issues in a holistic rather than a reductionist way, and many scientists use a holistic paradigm.When the terms are used in a scientific context, holism and reductionism refer primarily to what sorts of models or theories offer valid explanations of the natural world; the scientific method of falsifying hypotheses, checking empirical data against theory, is largely unchanged, but the method guides which theories are considered.
In many cases (such as the kinetic theory of gases), given a good understanding of the components of the system, one can predict all the important properties of the system as a whole. In other systems, especially concerned with life and life's emergent properties (morphogenesis, autopoiesis, and metabolism), emergent properties of the system are said to be almost impossible to predict from knowledge of the parts of the system. Complexity theory studies systems and properties of the latter type.
Alfred North Whitehead's metaphysics opposed reductionism. He refers to this as the "fallacy of the misplaced concreteness". His scheme was to frame a rational, general understanding of phenomena, derived from our reality.
Ecologist Sven Erik Jorgensen makes both theoretical and practical arguments for a holistic method in certain topics of science, especially ecology. He argues that many systems are so complex that they can ever be described in complete detail. In analogy to the Heisenberg uncertainty principle in physics, he argues that many interesting ecological phenomena cannot be replicated in laboratory conditions, and so cannot be measured or observed without changing the system in some way. He also indicates the importance of inter-connectedness in biological systems. He believes that science can only progress by outlining questions that are unanswerable and by using models that do not try to explain everything in terms of smaller hierarchical levels of organization, but instead model them on the scale of the system itself, taking into account some (but not all) factors from levels higher and lower in the hierarchy.
In cognitive psychology, George Kelly developed "constructive alternativism" as a form of personal construct psychology and an alternative to what he considered "accumulative fragmentalism". For this theory, knowledge is seen as the construction of successful mental models of the exterior world, rather than the accumulation of independent "nuggets of truth".
An alternative term for ontological reductionism is fragmentalism,often used in a pejorative sense. Anti-realists use the term fragmentalism in arguments that the world does not exist of separable entities, instead consisting of wholes. For example, advocates of this idea claim that:
The linear deterministic approach to nature and technology promoted a fragmented perception of reality, and a loss of the ability to foresee, to adequately evaluate, in all their complexity, global crises in ecology, civilization and education.
The term fragmentalism is usually applied to reductionist modes of thought, often with the related pejorative term scientism . This usage is popular among some ecological activists:
There is a need now to move away from scientism and the ideology of cause-and-effect determinism toward a radical empiricism, such as William James proposed, as an epistemology of science.
These perspectives are not new; during the early 20th century, William James noted that rationalist science emphasized what he called fragmentation and disconnection.
Such opinions also motivate many criticisms of the scientific method:
The scientific method only acknowledges monophasic consciousness. The method is a specialized system that emphasizes studying small and distinctive parts in isolation, which results in fragmented knowledge.
Materialism is a form of philosophical monism that holds that matter is the fundamental substance in nature, and that all things, including mental states and consciousness, are results of material interactions. According to philosophical materialism, mind and consciousness are by-products or epiphenomena of material processes, without which they cannot exist. This concept directly contrasts with idealism, where mind and consciousness are first-order realities to which matter is subject and material interactions are secondary.
In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own. These properties or behaviors emerge only when the parts interact in a wider whole. For example, smooth forward motion emerges when a bicycle and its rider interoperate, but neither part can produce the behavior on their own.
Reality is the sum or aggregate of all that is real or existent, as opposed to that which is only imaginary. The term is also used to refer to the ontological status of things, indicating their existence. In physical terms, reality is the totality of the universe, known and unknown. Philosophical questions about the nature of reality or existence or being are considered under the rubric of ontology, which is a major branch of metaphysics in the Western philosophical tradition. Ontological questions also feature in diverse branches of philosophy, including the philosophy of science, philosophy of religion, philosophy of mathematics, and philosophical logic. These include questions about whether only physical objects are real, whether reality is fundamentally immaterial, whether hypothetical unobservable entities posited by scientific theories exist, whether God exists, whether numbers and other abstract objects exist, and whether possible worlds exist.
Vitalism is the belief that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things". Where vitalism explicitly invokes a vital principle, that element is often referred to as the "vital spark", "energy" or "élan vital", which some equate with the soul. In the 18th and 19th centuries vitalism was discussed among biologists, between those who felt that the known mechanics of physics would eventually explain the difference between life and non-life and vitalists who argued that the processes of life could not be reduced to a mechanistic process. Some vitalist biologists proposed testable hypotheses meant to show inadequacies with mechanistic explanations, but these experiments failed to provide support for vitalism. Biologists now consider vitalism in this sense to have been refuted by empirical evidence, and hence regard it as a superseded scientific theory, according to Elizabeth Ann Williams.
"The Unreasonable Effectiveness of Mathematics in the Natural Sciences" is the title of an article published in 1960 by the physicist Eugene Wigner. In the paper, Wigner observed that the mathematical structure of a physical theory often points the way to further advances in that theory and even to empirical predictions.
Consilience: The Unity of Knowledge is a 1998 book by biologist E. O. Wilson, in which the author discusses methods that have been used to unite the sciences and might in the future unite them with the humanities. Wilson uses the term consilience to describe the synthesis of knowledge from different specialized fields of human endeavor.
In philosophy of science and in epistemology, instrumentalism is a methodological view that ideas are useful instruments, and that the worth of an idea is based on how effective it is in explaining and predicting phenomena. Instrumentalism is a pragmatic philosophy of John Dewey that thought is an instrument for solving practical problems, and that truth is not fixed but changes as problems change. Instrumentalism is the view that scientific theories are useful tools for predicting phenomena instead of true or approximately true descriptions.
In philosophy, emergentism is the belief in emergence, particularly as it involves consciousness and the philosophy of mind, and as it contrasts with reductionism. A property of a system is said to be emergent if it is a new outcome of some other properties of the system and their interaction, while it is itself different from them. Emergent properties are not identical with, reducible to, or deducible from the other properties. The different ways in which this independence requirement can be satisfied lead to variant types of emergence.
Holism in science, or holistic science, is an approach to research that emphasizes the study of complex systems. Systems are approached as coherent wholes whose component parts are best understood in context and in relation to one another and to the whole.
Scientific formalism is a family of approaches to the presentation of science. It is viewed as an important part of the scientific method, especially in the physical sciences.
The philosophy of biology is a subfield of philosophy of science, which deals with epistemological, metaphysical, and ethical issues in the biological and biomedical sciences. Although philosophers of science and philosophers generally have long been interested in biology, philosophy of biology only emerged as an independent field of philosophy in the 1960s and 1970s. Philosophers of science then began paying increasing attention to biology, from the rise of Neodarwinism in the 1930s and 1940s to the discovery of the structure of DNA in 1953 to more recent advances in genetic engineering. Other key ideas include the reduction of all life processes to biochemical reactions, and the incorporation of psychology into a broader neuroscience.
Hempel's dilemma is a question first asked by the philosopher Carl Hempel. It has relevance to naturalism and physicalism in philosophy, and to philosophy of mind.
Multiple realizability, in the philosophy of mind, is the thesis that the same mental property, state, or event can be implemented by different physical properties, states, or events. Philosophers of mind have used multiple realizability to argue that that mental states are not the same as — and cannot be reduced to — physical states. They have also used it to defend many versions of functionalism, especially machine-state functionalism. In recent years, however, multiple realizability has been used to attack functionalism, the theory that it was originally used to defend. As a result, functionalism has fallen out of favor in the philosophy of mind.
Antireductionism is the position in science and metaphysics that stands in contrast to reductionism (anti-holism) by advocating that not all properties of a system can be explained in terms of its constituent parts and their interactions.
Developmental systems theory (DST) is an overarching theoretical perspective on biological development, heredity, and evolution. It emphasizes the shared contributions of genes, environment, and epigenetic factors on developmental processes. DST, unlike conventional scientific theories, is not directly used to help make predictions for testing experimental results; instead, it is seen as a collection of philosophical, psychological, and scientific models of development and evolution. As a whole, these models argue the inadequacy of the modern evolutionary synthesis on the roles of genes and natural selection as the principle explanation of living structures. Developmental systems theory embraces a large range of positions that expand biological explanations of organismal development and hold modern evolutionary theory as a misconception of the nature of living processes.
In the science of biology, a mechanism is a system of causally interacting parts and processes that produce one or more effects. Scientists explain phenomena by describing mechanisms that could produce the phenomena. For example, natural selection is a mechanism of biological evolution; other mechanisms of evolution include genetic drift, mutation, and gene flow. In ecology, mechanisms such as predation and host-parasite interactions produce change in ecological systems. In practice, no description of a mechanism is ever complete because not all details of the parts and processes of a mechanism are fully known. For example, natural selection is a mechanism of evolution that includes countless, inter-individual interactions with other individuals, components, and processes of the environment in which natural selection operates.
In philosophy of science, intertheoretic reduction occurs when a reducing theory makes predictions that perfectly or almost perfectly match the predictions of a reduced theory, while the reducing theory explains or predicts a wider range of phenomena under more general conditions. Special relativity, for example, can be reduced to Newtonian mechanics for velocities far less than c.
Fragmentalism is a view that holds that the world consists of individual and independent objects. The term contends that the world is indeed composed of separable parts, and that it is chiefly knowable through the study of these component parts, rather than through wholes. It therefore stands opposed to holistic interpretations of phenomena.
"The Fragmentalists carved the universe up into smaller and smaller pieces until they reached such a fine level of subdivision that they could no longer observe the pieces directly." "As the tale of the Fragmentalists demonstrates, reductionist science usually looks for a mathematical equation, formula, or process that describes general features of the universe."
An integrative level, or level of organization, is a set of phenomena emerging from pre-existing phenomena of a lower level. The levels concept is an intellectual framework for structuring reality. It arranges all material entities and all processes in the universe into a hierarchy based on how complex the entity's organization is. When arranged this way, each entity is three things at the same time: It is made up of parts from the previous level below. It is a whole in its own right. And it is a part of the whole that is on the next level above. Typical examples include life emerging from non-living substances, and consciousness emerging from nervous systems.
Epistemological pluralism is a term used in philosophy, economics, and virtually any field of study to refer to different ways of knowing things, different epistemological methodologies for attaining a fuller description of a particular field. A particular form of epistemological pluralism is dualism, for example, the separation of methods for investigating mind from those appropriate to matter. By contrast, monism is the restriction to a single approach, for example, reductionism, which asserts the study of all phenomena can be seen as finding relations to some few basic entities.
|Look up reductionism in Wiktionary, the free dictionary.|
|Wikimedia Commons has media related to Reductionism .|