English[edit]
Etymology[edit]
From Middle French théorie, from Late Latin theōria, from Ancient Greek θεωρία (theōría, “contemplation, speculation, a looking at, things looked at”), from θεωρέω (theōréō, “I look at, view, consider, examine”), from θεωρός (theōrós, “spectator”), from θέα (théa, “view”) + ὁράω (horáō, “I see, look”) [i. e. θέαν ὁράω (théan horáō, “see, look at a view; survey + genitive”)].
Pronunciation[edit]
- (Received Pronunciation, General Australian) IPA(key): /ˈθɪə.ɹi/, /ˈθiː.ə.ɹi/, /ˈθɪɹ.i/
- (General American) IPA(key): /ˈθɪɚ.i/, /ˈθi.ə.ɹi/
-
- Rhymes: -ɪəɹi, -iːəɹi
Noun[edit]
theory (countable and uncountable, plural theories)
- A description of an event or system that is considered to be accurate.
- 1646, Thomas Browne, Pseudodoxia Epidemica, VII.19:
- As they encrease the hatred of vice in some, so doe they enlarge the theory of wickednesse in all.
- 1646, Thomas Browne, Pseudodoxia Epidemica, VII.19:
- (sciences) A coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed; a hypothesis confirmed by observation, experiment etc. [from 17th c.]
- 1843, John Stuart Mill, «»A System of Logic, Ratiocinative and Inductive, …, Bk V, Ch 7:
- In its most proper acceptation, theory means the completed result of philosophical induction from experience.
-
1990, Tony Bennett, Outside Literature, page 139:
-
Does this mean, then, that there can be no such thing as a theory of literature?
-
- 2002, Duncan Steel, The Guardian, 23 May 2002:
- It was only when Einstein’s theory of relativity was published in 1915 that physicists could show that Mercury’s «anomaly» was actually because Newton’s gravitational theory was incomplete.
- 2003, Bill Bryson, A Short History of Nearly Everything, BCA, p. 118:
- The world would need additional decades […] before the Big Bang would begin to move from interesting idea to established theory.
- 2009, Richard Dawkins, The Greatest Show On Earth: The Evidence for Evolution, Bantam, p. 10:
- Scientists and creationists are understanding the word «theory» in two very different senses. Evolution is a theory in the same sense as the heliocentric theory. In neither case should the word «only» be used, as in «only a theory«.
-
2012 January 1, Michael Riordan, “Tackling Infinity”, in American Scientist[1], volume 100, number 1, archived from the original on 30 April 2013, page 86:
-
Some of the most beautiful and thus appealing physical theories, including quantum electrodynamics and quantum gravity, have been dogged for decades by infinities that erupt when theorists try to prod their calculations into new domains. Getting rid of these nagging infinities has probably occupied far more effort than was spent in originating the theories.
-
- 1843, John Stuart Mill, «»A System of Logic, Ratiocinative and Inductive, …, Bk V, Ch 7:
- (uncountable) The underlying principles or methods of a given technical skill, art etc., as opposed to its practice. [from 17th c.]
-
1998, Elizabeth Souritz, The Great History of Russian Ballet:
-
Lopukhov wrote a number of books and articles on ballet theory, as well as his memoirs.
-
-
- (mathematics) A field of study attempting to exhaustively describe a particular class of constructs. [from 18th c.]
- Knot theory classifies the mappings of a circle into 3-space.
- A hypothesis or conjecture. [from 18th c.]
-
1999, Wes DeMott, Vapors:
-
It’s just a theory I have, and I wonder if women would agree. But don’t men say a lot about themselves when a short-skirted woman slides out of a car or chair?
-
- 2003, Sean Coughlan, The Guardian, 21 Jun 2003:
- The theory is that by stripping costs to the bone, they are able to offer ludicrously low fares.
-
- (countable, logic) A set of axioms together with all statements derivable from them; or, a set of statements which are deductively closed. Equivalently, a formal language plus a set of axioms (from which can then be derived theorems). The statements may be required to all be bound (i.e., to have no free variables).
- A theory is consistent if it has a model.
- (obsolete) Mental conception; reflection, consideration. [16th–18th c.]
Usage notes[edit]
In scientific discourse, the sense “unproven conjecture” is discouraged (with hypothesis or conjecture preferred), due to unintentional ambiguity and intentional equivocation with the sense “well-developed statement or structure”.
Synonyms[edit]
- See also Thesaurus:supposition
Meronyms[edit]
- (in logic): axioms
Holonyms[edit]
- (in logic): formal system
Derived terms[edit]
- acoustic theory
- algorithmic information theory
- antenna theory
- atomic theory
- catastrophe theory
- category theory
- cell theory
- chaos theory
- circuit theory
- complexity theory
- computation theory
- control theory
- critical theory
- decision theory
- domino theory
- extreme value theory
- game theory
- giant impact theory
- graph theory
- group theory
- in theory
- information theory
- kinetic theory of gases
- knot theory
- literary theory
- M-theory
- music theory
- number theory
- opponent-process theory
- phlogiston theory
- probability theory
- proof theory
- quantum field theory
- rational choice theory
- set theory
- signal theory
- social theory
- spectral theory
- systems theory
- theory of gravity
- theory of relativity
- theory of truth
- Theory X
- Theory Y
- theoryhead
- type theory
- value theory
- virtue theory
[edit]
- theorem
- theoretical
- theorise, theorize
Translations[edit]
a coherent set of statements attempting to explain observed phenomena
- Albanian: teori (sq) f
- Arabic: نَظَرِيَّة (ar) f (naẓariyya)
- Armenian: տեսություն (hy) (tesutʿyun), թեորիա (hy) (tʿeoria)
- Azerbaijani: nəzəriyyə, teoriya
- Belarusian: тэо́рыя f (teóryja)
- Bengali: তত্ত্ব (bn) (tottto)
- Bulgarian: тео́рия (bg) f (teórija)
- Burmese: သီအိုရီ (my) (siuiri)
- Catalan: teoria (ca) f
- Chinese:
- Mandarin: 理論/理论 (zh) (lǐlùn), 學說/学说 (zh) (xuéshuō)
- Czech: teorie (cs) f
- Danish: teori c
- Dutch: theorie (nl) f
- Esperanto: teorio
- Estonian: teooria (et)
- Finnish: teoria (fi)
- French: théorie (fr) f
- Galician: teoría (gl) f
- Georgian: თეორია (teoria)
- German: Theorie (de) f
- Greek: θεωρία (el) f (theoría)
- Haitian Creole: teori
- Hebrew: תּוֹרָה (he) f (torá), תֵּאוֹרְיָה f (teórya)
- Hindi: सिद्धांत (hi) m (siddhānt), नज़रिया m (nazriyā), तथ्य (hi) m (tathya)
- Hungarian: elmélet (hu)
- Icelandic: kenning f
- Ido: teorio (io)
- Indonesian: teori (id)
- Irish: teoiric f
- Old Irish: teöir f, teoiricecht f (medical)
- Italian: teoria (it) f
- Japanese: 理論 (ja) (りろん, riron), 学説 (ja) (がくせつ, gakusetsu)
- Kazakh: теория (kk) (teoriä)
- Khmer: ទ្រឹស្ដី (km) (trɨhsdəy)
- Korean: 이론(理論) (ko) (iron), 리론(理論) (ko) (riron) (North Korea), 학설(學說) (ko) (hakseol)
- Kyrgyz: теория (ky) (teoriya)
- Lao: ທິດສະດີ (lo) (thit sa dī)
- Latvian: teorija f
- Lithuanian: teorija f
- Macedonian: теорија f (teorija)
- Malay: teori (ms)
- Malayalam: സിദ്ധാന്തം (ml) (siddhāntaṃ)
- Maltese: teorija f
- Maori: ariā
- Mongolian:
- Cyrillic: онол (mn) (onol)
- Moroccan Amazigh: ⵜⵉⵥⵕⵉ (tiẓṛi)
- Norwegian:
- Bokmål: teori m
- Nynorsk: teori m
- Occitan: teoria (oc) f
- Pashto: نظريه (ps) f (nazaryá), تيوري (ps) f (tyorí)
- Persian: نظریه (fa) (nazariye), تئوری (fa) (te’ori)
- Polish: teoria (pl) f
- Portuguese: teoria (pt) f
- Romanian: teorie (ro) f
- Russian: тео́рия (ru) f (teórija)
- Serbo-Croatian:
- Cyrillic: тѐо̄рија f
- Roman: tèōrija (sh) f
- Slovak: teória f
- Slovene: teorija (sl) f
- Spanish: teoría (es) f
- Swedish: teori (sv) c
- Tagalog: huna
- Tajik: назария (tg) (nazariya), теория (teoriya)
- Thai: ทฤษฎี (th) (trít-sà-dii)
- Turkish: kuram (tr), nazariye (tr) (obsolecent), teori (tr)
- Turkmen: teoriýa
- Ukrainian: тео́рія f (teórija)
- Urdu: نظریہ f (nazariyā)
- Uyghur: نەزەرىيە (nezeriye)
- Uzbek: nazariya (uz), teoriya (uz)
- Vietnamese: lý thuyết (vi), lý luận (vi), học thuyết (vi)
- Volapük: teorod (vo)
- Welsh: damcaniaeth f
- Yiddish: טעאָריע f (teorye)
an unproven conjecture
- Arabic: نَظَرِيَّة (ar) f (naẓariyya)
- Armenian: տեսություն (hy) (tesutʿyun)
- Bulgarian: хипотеза (bg) f (hipoteza)
- Catalan: teoria (ca) f
- Chinese:
- Mandarin: 理論/理论 (zh) (lǐlùn)
- Danish: teori c
- Dutch: theorie (nl) f
- Finnish: teoria (fi)
- French: théorie (fr) f
- Galician: teoría (gl) f
- German: Theorie (de) f
- Greek: θεωρία (el) f (theoría)
- Hindi: नज़रिया m (nazriyā)
- Indonesian: teori (id)
- Irish: teoiric f
- Italian: teoria (it) f
- Japanese: 憶測 (ja) (おくそく, okusoku), 推測 (ja) (すいそく, suisoku), 推論 (ja) (すいろん, suiron), 見解 (ja) (けんかい, kenkai)
- Macedonian: теорија f (teorija)
- Malay: teori (ms)
- Maltese: teorija f
- Norwegian:
- Bokmål: teori m
- Nynorsk: teori m
- Polish: teoria (pl) f
- Portuguese: teoria (pt) f
- Romanian: teorie (ro) f
- Russian: тео́рия (ru) f (teórija), гипо́теза (ru) f (gipóteza)
- Scottish Gaelic: beachd-smaoin f
- Serbo-Croatian:
- Cyrillic: тѐо̄рија f
- Roman: tèōrija (sh) f
- Spanish: teoría (es) f
- Swedish: teori (sv) c
- Tagalog: huna
- Thai: ทฤษฎี (th) (trít-sà-dii)
- Turkish: kuram (tr), nazariye (tr) (obsolecent), teori (tr)
- Volapük: teor (vo)
- Yiddish: טעאָריע f (teorye)
a field of study in mathematics
- Catalan: teoria (ca) f
- Chinese:
- Mandarin: 理論/理论 (zh) (lǐlùn), 學說/学说 (zh) (xuéshuō)
- Czech: teorie (cs) f
- Danish: teori c
- Dutch: theorie (nl) f
- Finnish: teoria (fi), oppi (fi)
- French: théorie (fr) f
- Galician: teoría (gl) f
- German: Theorie (de) f
- Greek: θεωρία (el) f (theoría)
- Hindi: सिद्धांत (hi) m (siddhānt)
- Indonesian: teori (id)
- Irish: teoiric f
- Italian: teoria (it) f
- Japanese: 定理 (ja) (ていり, teiri), 理論 (ja) (りろん, riron), 学説 (ja) (がくせつ, gakusetsu)
- Macedonian: теорија f (teorija)
- Malay: teori (ms)
- Maltese: teorija
- Mongolian: онол (mn) (onol)
- Norwegian:
- Bokmål: teori m
- Nynorsk: teori n
- Polish: teoria (pl) f
- Portuguese: teoria (pt) f
- Romanian: teorie (ro)
- Russian: тео́рия (ru) f (teórija)
- Serbo-Croatian:
- Cyrillic: тѐо̄рија f
- Roman: tèōrija (sh) f
- Spanish: teoría (es) f
- Swedish: teori (sv) c
- Tagalog: huna
- Turkish: kuram (tr), nazariye (tr) (obsolecent), teori (tr)
- Welsh: damcaniaeth f
See also[edit]
- axiom
- postulate
- proposition
References[edit]
- theory at OneLook Dictionary Search
- theory in Keywords for Today: A 21st Century Vocabulary, edited by The Keywords Project, Colin MacCabe, Holly Yanacek, 2018.
- «theory» in Raymond Williams, Keywords (revised), 1983, Fontana Press, page 316.
- “theory”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.
Anagrams[edit]
- Yother, thyreo-
A theory is a rational type of abstract thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking is often associated with such processes as observational study or research. Theories may be scientific, belong to a non-scientific discipline, or no discipline at all. Depending on the context, a theory’s assertions might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings.
In modern science, the term «theory» refers to scientific theories, a well-confirmed type of explanation of nature, made in a way consistent with the scientific method, and fulfilling the criteria required by modern science. Such theories are described in such a way that scientific tests should be able to provide empirical support for it, or empirical contradiction («falsify») of it. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge,[1] in contrast to more common uses of the word «theory» that imply that something is unproven or speculative (which in formal terms is better characterized by the word hypothesis).[2] Scientific theories are distinguished from hypotheses, which are individual empirically testable conjectures, and from scientific laws, which are descriptive accounts of the way nature behaves under certain conditions.
Theories guide the enterprise of finding facts rather than of reaching goals, and are neutral concerning alternatives among values.[3]: 131 A theory can be a body of knowledge, which may or may not be associated with particular explanatory models. To theorize is to develop this body of knowledge.[4]: 46
The word theory or «in theory» is sometimes used erroneously by people to explain something which they individually did not experience or test before.[5] In those instances, semantically, it is being substituted for another concept, a hypothesis. Instead of using the word «hypothetically», it is replaced by a phrase: «in theory». In some instances the theory’s credibility could be contested by calling it «just a theory» (implying that the idea has not even been tested).[6] Hence, that word «theory» is very often contrasted to «practice» (from Greek praxis, πρᾶξις) a Greek term for doing, which is opposed to theory.[6] A «classical example» of the distinction between «theoretical» and «practical» uses the discipline of medicine: medical theory involves trying to understand the causes and nature of health and sickness, while the practical side of medicine is trying to make people healthy. These two things are related but can be independent, because it is possible to research health and sickness without curing specific patients, and it is possible to cure a patient without knowing how the cure worked.[a]
Ancient usage[edit]
The English word theory derives from a technical term in philosophy in Ancient Greek. As an everyday word, theoria, θεωρία, meant «looking at, viewing, beholding», but in more technical contexts it came to refer to contemplative or speculative understandings of natural things, such as those of natural philosophers, as opposed to more practical ways of knowing things, like that of skilled orators or artisans.[b] English-speakers have used the word theory since at least the late 16th century.[7] Modern uses of the word theory derive from the original definition, but have taken on new shades of meaning, still based on the idea of a theory as a thoughtful and rational explanation of the general nature of things.
Although it has more mundane meanings in Greek, the word θεωρία apparently developed special uses early in the recorded history of the Greek language. In the book From Religion to Philosophy, Francis Cornford suggests that the Orphics used the word theoria to mean «passionate sympathetic contemplation».[8] Pythagoras changed the word to mean «the passionless contemplation of rational, unchanging truth» of mathematical knowledge, because he considered this intellectual pursuit the way to reach the highest plane of existence.[9] Pythagoras emphasized subduing emotions and bodily desires to help the intellect function at the higher plane of theory. Thus, it was Pythagoras who gave the word theory the specific meaning that led to the classical and modern concept of a distinction between theory (as uninvolved, neutral thinking) and practice.[10]
Aristotle’s terminology, as already mentioned, contrasts theory with praxis or practice, and this contrast exists till today. For Aristotle, both practice and theory involve thinking, but the aims are different. Theoretical contemplation considers things humans do not move or change, such as nature, so it has no human aim apart from itself and the knowledge it helps create. On the other hand, praxis involves thinking, but always with an aim to desired actions, whereby humans cause change or movement themselves for their own ends. Any human movement that involves no conscious choice and thinking could not be an example of praxis or doing.[c]
Formality[edit]
Theories are analytical tools for understanding, explaining, and making predictions about a given subject matter. There are theories in many and varied fields of study, including the arts and sciences. A formal theory is syntactic in nature and is only meaningful when given a semantic component by applying it to some content (e.g., facts and relationships of the actual historical world as it is unfolding). Theories in various fields of study are expressed in natural language, but are always constructed in such a way that their general form is identical to a theory as it is expressed in the formal language of mathematical logic. Theories may be expressed mathematically, symbolically, or in common language, but are generally expected to follow principles of rational thought or logic.
Theory is constructed of a set of sentences that are entirely true statements about the subject under consideration. However, the truth of any one of these statements is always relative to the whole theory. Therefore, the same statement may be true with respect to one theory, and not true with respect to another. This is, in ordinary language, where statements such as «He is a terrible person» cannot be judged as true or false without reference to some interpretation of who «He» is and for that matter what a «terrible person» is under the theory.[11]
Sometimes two theories have exactly the same explanatory power because they make the same predictions. A pair of such theories is called indistinguishable or observationally equivalent, and the choice between them reduces to convenience or philosophical preference.
The form of theories is studied formally in mathematical logic, especially in model theory. When theories are studied in mathematics, they are usually expressed in some formal language and their statements are closed under application of certain procedures called rules of inference. A special case of this, an axiomatic theory, consists of axioms (or axiom schemata) and rules of inference. A theorem is a statement that can be derived from those axioms by application of these rules of inference. Theories used in applications are abstractions of observed phenomena and the resulting theorems provide solutions to real-world problems. Obvious examples include arithmetic (abstracting concepts of number), geometry (concepts of space), and probability (concepts of randomness and likelihood).
Gödel’s incompleteness theorem shows that no consistent, recursively enumerable theory (that is, one whose theorems form a recursively enumerable set) in which the concept of natural numbers can be expressed, can include all true statements about them. As a result, some domains of knowledge cannot be formalized, accurately and completely, as mathematical theories. (Here, formalizing accurately and completely means that all true propositions—and only true propositions—are derivable within the mathematical system.) This limitation, however, in no way precludes the construction of mathematical theories that formalize large bodies of scientific knowledge.
Underdetermination[edit]
A theory is underdetermined (also called indeterminacy of data to theory) if a rival, inconsistent theory is at least as consistent with the evidence. Underdetermination is an epistemological issue about the relation of evidence to conclusions.
A theory that lacks supporting evidence is generally, more properly, referred to as a hypothesis.
Intertheoretic reduction and elimination[edit]
If a new theory better explains and predicts a phenomenon than an old theory (i.e., it has more explanatory power), we are justified in believing that the newer theory describes reality more correctly. This is called an intertheoretic reduction because the terms of the old theory can be reduced to the terms of the new one. For instance, our historical understanding about sound, «light» and heat have been reduced to wave compressions and rarefactions, electromagnetic waves, and molecular kinetic energy, respectively. These terms, which are identified with each other, are called intertheoretic identities. When an old and new theory are parallel in this way, we can conclude that the new one describes the same reality, only more completely.
When a new theory uses new terms that do not reduce to terms of an older theory, but rather replace them because they misrepresent reality, it is called an intertheoretic elimination. For instance, the obsolete scientific theory that put forward an understanding of heat transfer in terms of the movement of caloric fluid was eliminated when a theory of heat as energy replaced it. Also, the theory that phlogiston is a substance released from burning and rusting material was eliminated with the new understanding of the reactivity of oxygen.
Versus theorems[edit]
Theories are distinct from theorems. A theorem is derived deductively from axioms (basic assumptions) according to a formal system of rules, sometimes as an end in itself and sometimes as a first step toward being tested or applied in a concrete situation; theorems are said to be true in the sense that the conclusions of a theorem are logical consequences of the axioms. Theories are abstract and conceptual, and are supported or challenged by observations in the world. They are ‘rigorously tentative’, meaning that they are proposed as true and expected to satisfy careful examination to account for the possibility of faulty inference or incorrect observation. Sometimes theories are incorrect, meaning that an explicit set of observations contradicts some fundamental objection or application of the theory, but more often theories are corrected to conform to new observations, by restricting the class of phenomena the theory applies to or changing the assertions made. An example of the former is the restriction of classical mechanics to phenomena involving macroscopic length scales and particle speeds much lower than the speed of light.
The theory–practice gap[edit]
Theory is often distinguished from practice. The question of whether theoretical models of work are relevant to work itself is of interest to scholars of professions such as medicine, engineering, and law, and management.[12]: 802
This gap between theory and practice has been framed as a knowledge transfer where there is a task of translating research knowledge to be application in practice, and ensuring that practitioners are made aware of it academics have been criticized for not attempting to transfer the knowledge they produce to practitioners.[12]: 804 [13] Another framing supposes that theory and knowledge seek to understand different problems and model the world in different words (using different ontologies and epistemologies) . Another framing says that research does not produce theory that is relevant to practice.[12]: 803
In the context of management, Van de Van and Johnson propose a form of engaged scholarship where scholars examine problems that occur in practice, in an interdisciplinary fashion, producing results that create both new practical results as well as new theoretical models, but targeting theoretical results shared in an academic fashion.[12]: 815 They use a metaphor of «arbitrage» of ideas between disciplines, distinguishing it from collaboration.[12]: 803
Scientific[edit]
In science, the term «theory» refers to «a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.»[14][15] Theories must also meet further requirements, such as the ability to make falsifiable predictions with consistent accuracy across a broad area of scientific inquiry, and production of strong evidence in favor of the theory from multiple independent sources (consilience).
The strength of a scientific theory is related to the diversity of phenomena it can explain, which is measured by its ability to make falsifiable predictions with respect to those phenomena. Theories are improved (or replaced by better theories) as more evidence is gathered, so that accuracy in prediction improves over time; this increased accuracy corresponds to an increase in scientific knowledge. Scientists use theories as a foundation to gain further scientific knowledge, as well as to accomplish goals such as inventing technology or curing diseases.
Definitions from scientific organizations[edit]
The United States National Academy of Sciences defines scientific theories as follows:
The formal scientific definition of «theory» is quite different from the everyday meaning of the word. It refers to a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence. Many scientific theories are so well established that no new evidence is likely to alter them substantially. For example, no new evidence will demonstrate that the Earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the Earth is not divided into solid plates that have moved over geological timescales (the theory of plate tectonics) … One of the most useful properties of scientific theories is that they can be used to make predictions about natural events or phenomena that have not yet been observed.[16]
From the American Association for the Advancement of Science:
A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not «guesses» but reliable accounts of the real world. The theory of biological evolution is more than «just a theory.» It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact.[15]
The term theory is not appropriate for describing scientific models or untested, but intricate hypotheses.
Philosophical views[edit]
The logical positivists thought of scientific theories as deductive theories—that a theory’s content is based on some formal system of logic and on basic axioms. In a deductive theory, any sentence which is a logical consequence of one or more of the axioms is also a sentence of that theory.[11] This is called the received view of theories.
In the semantic view of theories, which has largely replaced the received view,[17][18] theories are viewed as scientific models. A model is a logical framework intended to represent reality (a «model of reality»), similar to the way that a map is a graphical model that represents the territory of a city or country. In this approach, theories are a specific category of models that fulfill the necessary criteria. (See Theories as models for further discussion.)
In physics[edit]
In physics the term theory is generally used for a mathematical framework—derived from a small set of basic postulates (usually symmetries, like equality of locations in space or in time, or identity of electrons, etc.)—which is capable of producing experimental predictions for a given category of physical systems. One good example is classical electromagnetism, which encompasses results derived from gauge symmetry (sometimes called gauge invariance) in a form of a few equations called Maxwell’s equations. The specific mathematical aspects of classical electromagnetic theory are termed «laws of electromagnetism», reflecting the level of consistent and reproducible evidence that supports them. Within electromagnetic theory generally, there are numerous hypotheses about how electromagnetism applies to specific situations. Many of these hypotheses are already considered adequately tested, with new ones always in the making and perhaps untested.
Regarding the term «theoretical»[edit]
Certain tests may be infeasible or technically difficult. As a result, theories may make predictions that have not been confirmed or proven incorrect. These predictions may be described informally as «theoretical». They can be tested later, and if they are incorrect, this may lead to revision, invalidation, or rejection of the theory.
[19]
Mathematical[edit]
In mathematics the use of the term theory is different, necessarily so, since mathematics contains no explanations of natural phenomena, per se, even though it may help provide insight into natural systems or be inspired by them. In the general sense, a mathematical theory is a branch of or topic in mathematics, such as Set theory, Number theory, Group theory, Probability theory, Game theory, Control theory, Perturbation theory, etc., such as might be appropriate for a single textbook.
In the same sense, but more specifically, the word theory is an extensive, structured collection of theorems, organized so that the proof of each theorem only requires the theorems and axioms that preceded it (no circular proofs), occurs as early as feasible in sequence (no postponed proofs), and the whole is as succinct as possible (no redundant proofs).[d] Ideally, the sequence in which the theorems are presented is as easy to understand as possible, although illuminating a branch of mathematics is the purpose of textbooks, rather than the mathematical theory they might be written to cover.
Philosophical[edit]
A theory can be either descriptive as in science, or prescriptive (normative) as in philosophy.[20] The latter are those whose subject matter consists not of empirical data, but rather of ideas. At least some of the elementary theorems of a philosophical theory are statements whose truth cannot necessarily be scientifically tested through empirical observation.
A field of study is sometimes named a «theory» because its basis is some initial set of assumptions describing the field’s approach to the subject. These assumptions are the elementary theorems of the particular theory, and can be thought of as the axioms of that field. Some commonly known examples include set theory and number theory; however literary theory, critical theory, and music theory are also of the same form.
Metatheory[edit]
One form of philosophical theory is a metatheory or meta-theory. A metatheory is a theory whose subject matter is some other theory or set of theories. In other words, it is a theory about theories. Statements made in the metatheory about the theory are called metatheorems.
Political[edit]
A political theory is an ethical theory about the law and government. Often the term «political theory» refers to a general view, or specific ethic, political belief or attitude, thought about politics.
Jurisprudential[edit]
In social science, jurisprudence is the philosophical theory of law. Contemporary philosophy of law addresses problems internal to law and legal systems, and problems of law as a particular social institution.
Examples[edit]
Most of the following are scientific theories. Some are not, but rather encompass a body of knowledge or art, such as Music theory and Visual Arts Theories.
- Anthropology: Carneiro’s circumscription theory
- Astronomy: Alpher–Bethe–Gamow theory — B2FH Theory — Copernican theory — Newton’s theory of gravitation — Hubble’s law — Kepler’s laws of planetary motion Ptolemaic theory
- Biology: Cell theory — Chemiosmotic theory — Evolution — Germ theory — Symbiogenesis
- Chemistry: Molecular theory — Kinetic theory of gases — Molecular orbital theory — Valence bond theory — Transition state theory — RRKM theory — Chemical graph theory — Flory–Huggins solution theory — Marcus theory — Lewis theory (successor to Brønsted–Lowry acid–base theory) — HSAB theory — Debye–Hückel theory — Thermodynamic theory of polymer elasticity — Reptation theory — Polymer field theory — Møller–Plesset perturbation theory — density functional theory — Frontier molecular orbital theory — Polyhedral skeletal electron pair theory — Baeyer strain theory — Quantum theory of atoms in molecules — Collision theory — Ligand field theory (successor to Crystal field theory) — Variational transition-state theory — Benson group increment theory — Specific ion interaction theory
- Climatology: Climate change theory (general study of climate changes) and anthropogenic climate change (ACC)/ global warming (AGW) theories (due to human activity)
- Computer Science: Automata theory — Queueing theory
- Cosmology: Big Bang Theory — Cosmic inflation — Loop quantum gravity — Superstring theory — Supergravity — Supersymmetric theory — Multiverse theory — Holographic principle — Quantum gravity — M-theory
- Economics: Macroeconomic theory — Microeconomic theory — Law of Supply and demand
- Education: Constructivist theory — Critical pedagogy theory — Education theory — Multiple intelligence theory — Progressive education theory
- Engineering: Circuit theory — Control theory — Signal theory — Systems theory — Information theory
- Film: Film theory
- Geology: Plate tectonics
- Humanities: Critical theory
- Jurisprudence or ‘Legal theory’: Natural law — Legal positivism — Legal realism — Critical legal studies
- Law: see Jurisprudence; also Case theory
- Linguistics: X-bar theory — Government and Binding — Principles and parameters — Universal grammar
- Literature: Literary theory
- Mathematics: Approximation theory — Arakelov theory — Asymptotic theory — Bifurcation theory — Catastrophe theory — Category theory — Chaos theory — Choquet theory — Coding theory — Combinatorial game theory — Computability theory — Computational complexity theory — Deformation theory — Dimension theory — Ergodic theory — Field theory — Galois theory — Game theory — Gauge theory — Graph theory — Group theory — Hodge theory — Homology theory — Homotopy theory — Ideal theory — Intersection theory — Invariant theory — Iwasawa theory — K-theory — KK-theory — Knot theory — L-theory — Lie theory — Littlewood–Paley theory — Matrix theory — Measure theory — Model theory — Module theory — Morse theory — Nevanlinna theory — Number theory — Obstruction theory — Operator theory — Order theory — PCF theory — Perturbation theory — Potential theory — Probability theory — Ramsey theory — Rational choice theory — Representation theory — Ring theory — Set theory — Shape theory — Small cancellation theory — Spectral theory — Stability theory — Stable theory — Sturm–Liouville theory — Surgery theory — Twistor theory — Yang–Mills theory
- Music: Music theory
- Philosophy: Proof theory — Speculative reason — Theory of truth — Type theory — Value theory — Virtue theory
- Physics: Acoustic theory — Antenna theory — Atomic theory — BCS theory — Conformal field theory — Dirac hole theory — Dynamo theory — Landau theory — M-theory — Perturbation theory — Theory of relativity (successor to classical mechanics) — Gauge theory — Quantum field theory — Scattering theory — String theory — Quantum information theory
- Psychology: Theory of mind — Cognitive dissonance theory — Attachment theory — Object permanence — Poverty of stimulus — Attribution theory — Self-fulfilling prophecy — Stockholm syndrome
- Public Budgeting: Incrementalism — Zero-based budgeting
- Public Administration: Organizational theory
- Semiotics: Intertheoricity – Transferogenesis
- Sociology: Critical theory — Engaged theory — Social theory — Sociological theory – Social capital theory
- Statistics: Extreme value theory
- Theatre: Performance theory
- Visual Arts: Aesthetics — Art educational theory — Architecture — Composition — Anatomy — Color theory — Perspective — Visual perception — Geometry — Manifolds
- Other: Obsolete scientific theories
See also[edit]
- Falsifiability
- Hypothesis testing
- Physical law
- Predictive power
- Testability
- Theoretical definition
Notes[edit]
- ^ See for example Hippocrates Praeceptiones, Part 1. Archived 12 September 2014 at the Wayback Machine
- ^ The word theoria occurs in Greek philosophy, for example, that of Plato. It is a statement of how and why particular facts are related. It is related to words for θεωρός «spectator», θέα thea «a view» + ὁρᾶν horan «to see», literally «looking at a show». See for example dictionary entries at Perseus website.
- ^ The LSJ cites two passages of Aristotle as examples, both from the Metaphysics and involving the definition of natural science: 11.1064a17, «it is clear that natural science (φυσικὴν ἐπιστήμην) must be neither practical (πρακτικὴν) nor productive (ποιητικὴν), but speculative (θεωρητικὴν)» and 6.1025b25, «Thus if every intellectual activity [διάνοια] is either practical or productive or speculative (θεωρητική), physics (φυσικὴ) will be a speculative [θεωρητική] science.» So Aristotle actually made a three way distinction between practical, theoretical and productive or technical—or between doing, contemplating or making. All three types involve thinking, but are distinguished by what causes the objects of thought to move or change.
- ^ Succinct in this sense refers to the whole collection of proofs, and means that any one proof contains no embedded stages that are equivalent to parts of proofs of later theorems.
References[edit]
Citations[edit]
- ^ Schafersman, Steven D. «An Introduction to Science».
- ^ National Academy of Sciences, Institute of Medicine (2008). Science, evolution, and creationism. Washington, D.C.: National Academies Press. p. 11. ISBN 978-0309105866. Retrieved 26 September 2015.
- ^ McMurray, Foster (July 1955). «Preface to an Autonomous Discipline of Education». Educational Theory. 5 (3): 129–140. doi:10.1111/j.1741-5446.1955.tb01131.x.
- ^ Thomas, Gary (2007). Education and theory : strangers in paradigms. Maidenhead: Open Univ. Press. ISBN 9780335211791.
- ^ What is a Theory?. American Museum of Natural History.
- ^ a b David J Pfeiffer. Scientific Theory vs Law. Science Journal (on medium.com). 30 January 2017
- ^ Harper, Douglas. «theory». Online Etymology Dictionary. Retrieved 18 July 2008.
- ^ Cornford, Francis Macdonald (8 November 1991). From religion to philosophy: a study in the origins of western speculation. Princeton University Press. p. 198. ISBN 978-0-691-02076-1.
- ^ Cornford, Francis M. (1991). From Religion to Philosophy: a study in the origins of western speculation. Princeton: Princeton University Press. p. 200. ISBN 0-691-02076-0.
- ^ Russell, Bertrand (1945). History of Western Philosophy.
- ^ a b Curry, Haskell, Foundations of Mathematical Logic
- ^ a b c d e Van De Ven, Andrew H.; Johnson, Paul E. (1 October 2006). «Knowledge for Theory and Practice». Academy of Management Review. 31 (4): 802–821. doi:10.5465/amr.2006.22527385. ISSN 0363-7425.
- ^ Beer, Michael (1 March 2001). «Why Management Research Findings Are Unimplementable: An Action Science Perspective». Reflections: The SoL Journal. 2 (3): 58–65. doi:10.1162/152417301570383.
- ^ National Academy of Sciences, 1999
- ^ a b «AAAS Evolution Resources».
- ^ Science, Evolution, and Creationism. National Academy of Sciences. 2008. doi:10.17226/11876. ISBN 978-0-309-10586-6.
- ^ Suppe, Frederick (1998). «Understanding Scientific Theories: An Assessment of Developments, 1969–1998» (PDF). Philosophy of Science. 67: S102–S115. doi:10.1086/392812. S2CID 37361274. Retrieved 14 February 2013.
- ^ Halvorson, Hans (2012). «What Scientific Theories Could Not Be» (PDF). Philosophy of Science. 79 (2): 183–206. CiteSeerX 10.1.1.692.8455. doi:10.1086/664745. S2CID 37897853. Retrieved 14 February 2013.
- ^ Bradford, Alina (25 March 2015). «What Is a Law in Science?». Live Science. Retrieved 1 January 2017.
- ^ Kneller, George Frederick (1964). Introduction to the philosophy of education. New York: J. Wiley. p. 93.
Sources[edit]
- Davidson Reynolds, Paul (1971). A primer in theory construction. Boston: Allyn and Bacon.
- Guillaume, Astrid (2015). « Intertheoricity: Plasticity, Elasticity and Hybridity of Theories. Part II: Semiotics of Transferogenesis », in Human and Social studies, Vol.4, N°2 (2015), éd.Walter de Gruyter, Boston, Berlin, pp. 59–77.
- Guillaume, Astrid (2015). « The Intertheoricity : Plasticity, Elasticity and Hybridity of Theories », in Human and Social studies, Vol.4, N°1 (2015), éd.Walter de Gruyter, Boston, Berlin, pp. 13–29.
- Hawking, Stephen (1996). A Brief History of Time (Updated and expanded ed.). New York: Bantam Books, p. 15.
- James, Paul (2006). Globalism, Nationalism, Tribalism: Bringing Theory Back In. London, England: Sage Publications.
- Matson, Ronald Allen, «Comparing scientific laws and theories», Biology, Kennesaw State University.
- Popper, Karl (1963), Conjectures and Refutations, Routledge and Kegan Paul, London, UK, pp. 33–39. Reprinted in Theodore Schick (ed., 2000), Readings in the Philosophy of Science, Mayfield Publishing Company, Mountain View, California, USA, pp. 9–13.
- Zima, Peter V. (2007). «What is theory? Cultural theory as discourse and dialogue». London: Continuum (translated from: Was ist Theorie? Theoriebegriff und Dialogische Theorie in der Kultur- und Sozialwissenschaften. Tübingen: A. Franke Verlag, 2004).
External links[edit]
- «How science works: Even theories change», Understanding Science by the University of California Museum of Paleontology.
- What is a Theory?
- Top Definitions
- Synonyms
- Quiz
- Related Content
- Examples
- British
- Scientific
- Cultural
This shows grade level based on the word’s complexity.
[ thee—uh-ree, theer-ee ]
/ ˈθi ə ri, ˈθɪər i /
This shows grade level based on the word’s complexity.
noun, plural the·o·ries.
a coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena: Einstein’s theory of relativity.
a proposed explanation whose status is still conjectural and subject to experimentation, in contrast to well-established propositions that are regarded as reporting matters of actual fact.
Mathematics. a body of principles, theorems, or the like, belonging to one subject: number theory.
the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.
a particular conception or view of something to be done or of the method of doing it; a system of rules or principles: conflicting theories of how children best learn to read.
contemplation or speculation: the theory that there is life on other planets.
guess or conjecture: My theory is that he never stops to think words have consequences.
QUIZ
CAN YOU ANSWER THESE COMMON GRAMMAR DEBATES?
There are grammar debates that never die; and the ones highlighted in the questions in this quiz are sure to rile everyone up once again. Do you know how to answer the questions that cause some of the greatest grammar debates?
Which sentence is correct?
Idioms about theory
in theory, ideally; hypothetically: In theory, mapping the human genome may lead to thousands of cures.
Origin of theory
First recorded in 1590–1600; from Late Latin theōria, from Greek theōría “a viewing, contemplating,” equivalent to theōr(eîn) “to view” + -ia noun suffix; see -y3
synonym study for theory
1, 2. In technical or scientific use, Theory, principle, and law represent established, evidence-based explanations accounting for currently known facts or phenomena or for historically verified experience: the theory of relativity, the germ theory of disease, the law of supply and demand, the principle of conservation of energy. Often the word law is used in reference to scientific facts that can be reduced to a mathematical formula: Newton’s laws of motion. In these contexts the terms theory and law often appear in well-established, fixed phrases and are not interchangeable. In both technical and nontechnical contexts, theory can also be synonymous with hypothesis, a conjecture put forth as a possible explanation of phenomena or relations, serving as a basis for thoughtful discussion and subsequent collection of data or engagement in scientific experimentation in order to rule out alternative explanations and reach the truth. In these contexts of early speculation, the words theory and hypothesis are often substitutable for one another: Remember, this idea is only a theory/hypothesis; Pasteur’s experiments helped prove the theory/hypothesis that germs cause disease. Obviously, certain theories that start out as hypothetical eventually receive enough supportive data and scientific findings to become established, verified explanations. Although they retain the term theory in their names, they have evolved from mere conjecture to scientifically accepted fact.
WORDS THAT MAY BE CONFUSED WITH theory
hypothesis, law, theory (see synonym study at the current entry)
Words nearby theory
theoretics, The Orient, Origin of Species, The, theorist, theorize, theory, theory-laden, theory of equations, Theory of Everything, theory of games, theory of mind
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Words related to theory
approach, argument, assumption, code, concept, doctrine, idea, ideology, method, philosophy, plan, position, premise, proposal, provision, rationale, scheme, speculation, suspicion, system
How to use theory in a sentence
-
“Our prosecutors have all too often inserted themselves into the political process based on the flimsiest of legal theories,” Barr went on.
-
Turn Wilson’s mathematical crank, and you get a related theory describing groups of those pieces — perhaps billiard ball molecules.
-
She also learns immediately that this theory is “not just incorrect but hateful, like saying that different races had different IQs” — and yet, “in my heart, I knew that Whorf was right,” that language does change the way you think.
-
It applies a different random error to each piece of information that’s encoded—which in theory makes it impossible to break without knowing the key.
-
Kindrachuk also works on ebola, and he says over the years many such theories have been put forth in scientific journals without provoking this kind of response.
-
But at the heart of this “Truther” conspiracy theory is the idea that “someone” wants to destroy Bill Cosby.
-
Is it sort of evidence of the Gladwellian 10,000 hours theory?
-
But a 2011 study of genetic evidence from 30 ethnic groups in India disproved this theory.
-
But, in theory, that started to change last week with the first meeting of SIX, the State Innovation Exchange.
-
So I was happy to see that the European theory of terroir was in action, promoting with pride the qualities of a specific region.
-
In the year of misery, of agony and suffering in general he had endured, he had settled upon one theory.
-
Dean Swift was indeed a misanthrope by theory, however he may have made exception to private life.
-
The other is the new theory: that the Bible is the work of many men whom God had inspired to speak or write the truth.
-
The evolution theory alleges that they were evolved, slowly, by natural processes out of previously existing matter.
-
And our surroundings at that particular moment were not the most favorable to coherent thought or plausible theory-building.
British Dictionary definitions for theory
noun plural -ries
a system of rules, procedures, and assumptions used to produce a result
abstract knowledge or reasoning
a speculative or conjectural view or ideaI have a theory about that
an ideal or hypothetical situation (esp in the phrase in theory)
a set of hypotheses related by logical or mathematical arguments to explain and predict a wide variety of connected phenomena in general termsthe theory of relativity
Word Origin for theory
C16: from Late Latin theōria, from Greek: a sight, from theōrein to gaze upon
Collins English Dictionary — Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for theory
A set of statements or principles devised to explain a group of facts or phenomena. Most theories that are accepted by scientists have been repeatedly tested by experiments and can be used to make predictions about natural phenomena. See Note at hypothesis.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for theory
In science, an explanation or model that covers a substantial group of occurrences in nature and has been confirmed by a substantial number of experiments and observations. A theory is more general and better verified than a hypothesis. (See Big Bang theory, evolution, and relativity.)
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Continue Learning about English Language Arts
What is the word origin for the word incredulous?
what is the word origin for incredulous
What is the origin of the word ballot?
the origin is where the word came from but the specific origin
of the word ballot is latin root word.
Origin of the word kitchen?
What is the origin of the word kitchen
What is the origin of the word rebellion?
The origin of the word rebellion is Latin.
What is the origin of the word stomach?
the origin of the word stomach : greek
A hypothesis is an assumption, an idea that is proposed for the sake of argument so that it can be tested to see if it might be true.
In the scientific method, the hypothesis is constructed before any applicable research has been done, apart from a basic background review. You ask a question, read up on what has been studied before, and then form a hypothesis.
A hypothesis is usually tentative; it’s an assumption or suggestion made strictly for the objective of being tested.
A theory, in contrast, is a principle that has been formed as an attempt to explain things that have already been substantiated by data. It is used in the names of a number of principles accepted in the scientific community, such as the Big Bang Theory. Because of the rigors of experimentation and control, it is understood to be more likely to be true than a hypothesis is.
In non-scientific use, however, hypothesis and theory are often used interchangeably to mean simply an idea, speculation, or hunch, with theory being the more common choice.
Since this casual use does away with the distinctions upheld by the scientific community, hypothesis and theory are prone to being wrongly interpreted even when they are encountered in scientific contexts—or at least, contexts that allude to scientific study without making the critical distinction that scientists employ when weighing hypotheses and theories.
The most common occurrence is when theory is interpreted—and sometimes even gleefully seized upon—to mean something having less truth value than other scientific principles. (The word law applies to principles so firmly established that they are almost never questioned, such as the law of gravity.)
This mistake is one of projection: since we use theory in general to mean something lightly speculated, then it’s implied that scientists must be talking about the same level of uncertainty when they use theory to refer to their well-tested and reasoned principles.
The distinction has come to the forefront particularly on occasions when the content of science curricula in schools has been challenged—notably, when a school board in Georgia put stickers on textbooks stating that evolution was «a theory, not a fact, regarding the origin of living things.» As Kenneth R. Miller, a cell biologist at Brown University, has said, a theory «doesn’t mean a hunch or a guess. A theory is a system of explanations that ties together a whole bunch of facts. It not only explains those facts, but predicts what you ought to find from other observations and experiments.”
While theories are never completely infallible, they form the basis of scientific reasoning because, as Miller said «to the best of our ability, we’ve tested them, and they’ve held up.»