This article has multiple issues. Please help improve it or discuss these issues on the talk page. It needs additional references or sources for verification. Tagged since March 2010. It may contain original research or unverifiable claims. Tagged since August 2008. It may contain an unpublished synthesis of published material that conveys ideas not verifiable with the given sources. Please help add reliable sources about this topic. Tagged since August 2008. Sir John Tenniel's illustration of the Caterpillar for Lewis Carroll's Alice's Adventures in Wonderland is noted for its ambiguous central figure whose head can be viewed as being a human male's face with a pointed nose and pointy chin or being the head end of an actual caterpillar with the right three "true" legs visible.1

Ambiguity is a term used in writing and math and under conditions where information can be understood or interpreted in more than one way and is distinct from vagueness which is a statement about the lack of precision contained or available in the information.

Context may play a role in resolving ambiguity. For example the same piece of information may be ambiguous in one context and unambiguous in another. Contents 1 Linguistic forms 2 Intentional application 2.1 Psychology and management 3 Music 4 Visual art 5 Constructed language 6 Mathematical notation 6.1 Names of functions 6.2 Expressions 6.3 Examples of potentially confusing ambiguous mathematical expressions 6.4 Notations in quantum optics and quantum mechanics 6.5 Ambiguous terms in physics and mathematics 7 Mathematical interpretation of ambiguity 8 Pedagogic use of ambiguous expressions 9 See also 10 References 11 External links Linguistic forms

The lexical ambiguity of a word or phrase contains in its having more than one meaning in the language to which the word belongs. "Meaning" hereby refers to whatever should be captured by a good dictionary. For instance the word "bank" has several distinct lexical definitions including "financial institution" and "edge of a river". Another example is as in apothecary. One could say "I bought herbs from the apothecary". This could mean you actually spoke to the apothecary (pharmacist) or went to the apothecary (pharmacy).

The context in which an ambiguous word is used often makes it evident which of the meanings is intended. If for instance someone says "I deposited $100 in the bank" most people would not think you used a shovel to dig in the mud. However some linguistic contexts do not provide sufficient information to disambiguate a used word. For example "Biweekly" can mean "fortnightly" (once every two weeks 26 times a year) OR "twice a week" (104 times a year). If "biweekly" is used in a conversation about a meeting schedule it may be difficult to infer which meaning was intended. Many peoplewho believe that such lexically ambiguous miscommunication-prone words should be avoided wherever possible since the user generally has to waste time effort and attention span to define what is meant when they are used.

Lexical ambiguity can be addressed by algorithmic methods that automatically associate the appropriate meaning with a word in context a task referred to as Word Sense Disambiguation.

The use of multi-defined words requires the author or speaker to clarify their context and sometimes elaborate on their specific intended meaning (in which case a less ambiguous term should have been used). The goal of clear concise communication is that the receiver(s) have no misunderstanding about what was meant to be conveyed. An exception to this could include a politician whose "weasel words" and obfuscation are necessary to gain support from multiple constituents with mutually exclusive conflicting desires from their candidate of choice. Ambiguity is a powerful tool of political science.

More problematic are words whose senses express closely related concepts. Good for example can mean "useful" or "functional" (Thats a good hammer) "exemplary" (Shes a good student) "pleasing" (This is good soup) "moral (a good person versus the lesson to be learned from a story) "righteous" etc. " I have a good daughter" is not clear about which sense is intended. The various ways to apply prefixes and suffixes can also create ambiguity ("unlockable" can mean "capable of being unlocked" or "impossible to lock").

Syntactic ambiguity arises when a phrase can be parsed in more than one way. Such phrases can be assigned different interpretations because different grammatical structures can be assigned to the same string of words.2 "He ate the cookies on the couch" for example could mean that he ate those cookies which were on the couch (as opposed to those that were on the table) or it could mean that he was sitting on the couch when he ate the cookies.

Spoken language can contain many more types of ambiguities where there is more than one way to compose a set of sounds into words for example "ice cream" and "I scream". Such ambiguity is generally resolved according to the context. A mishearing of such based on incorrectly resolved ambiguity is called a mondegreen. Semantic ambiguity arises when a word or concept has an inherently diffuse meaning based on widespread or informal usage. This is often the case for example with idiomatic expressions whose definitions are rarely or never well-defined and are presented in the context of a larger argument that invites a conclusion. For example "You could do with a new automobile. How about a test drive" The clause "You could do with" presents a statement with such wide possible interpretation as to be essentially meaningless.citation needed Lexical ambiguity is contrasted with semantic ambiguity. The former represents a choice between a finite number of known and meaningful context-dependent interpretations. The latter represents a choice between any number of possible interpretations none of which may have a standard agreed-upon meaning. This form of ambiguity is closely related to vagueness. Linguistic ambiguity can be a problem in law (see Ambiguity (law)) because the interpretation of written documents and oral agreements is often of paramount importance. Intentional application Philosophers (and other users of logic) spend a lot of time and effort searching for and removing (or intentionally adding) ambiguity in arguments because it can lead to incorrect conclusions and can be used to deliberately conceal bad arguments. For example a politician might say "I oppose taxes which hinder economic growth" an example of a glittering generality. Some will think he opposes taxes in general because they hinder economic growth. Others may think he opposes only those taxes that he believes will hinder economic growth. In writing the sentence can be rewritten to reduce possible misinterpretation either by adding a comma after "taxes" (to convey the first sense) or by changing "which" to "that" (to convey the second sense) or by rewriting it in other ways. The devious politician hopes that each constituent (politics) will interpret the statement in the most desirable way and think the politician supports everyone's opinion. However the opposite can also be true - An opponent can turn a positive statement into a bad one if the speaker uses ambiguity (intentionally or not). The logical fallacies of amphiboly and equivocation rely heavily on the use of ambiguous words and phrases. In Continental philosophy (particularly phenomenology and existentialism) there is much greater tolerance of ambiguity as it is generally seen as an integral part of the human condition. Martin Heidegger argued that the relation between the subject and object is ambiguous as is the relation of mind and body and part and whole.3 In Heidegger's phenomenology Dasein is always in a meaningful world but there is always an underlying background for every instance of signfication. Thus although some things may be certain they have little to do with Dasein's sense of care and existential anxiety e.g. in the face of death. In calling his work Being and Nothingness an "essay in phenomenological ontology" Jean-Paul Sartre follows Heidegger in defining the human essence as ambiguous or relating fundamentally to such ambiguity. Simone de Beauvoir tries to base an ethics on Heidegger's and Sartre's writings (The Ethics of Ambiguity) where she highlights the need to grapple with ambiguity: "as long as philosophers and they men have thought most of them have tried to mask it...And the ethics which they have proposed to their disciples has always pursued thre same goal. It has been a matter of eliminating the ambiguity by making oneself pure inwardness or pure externality by escaping from the sensible world or being engulfed by it by yielding to eternity or enclosing oneself in the pure moment.".4 Ethics cannot be based on the authoritative certainty given by mathematics and logic or prescribed directly from the empirical findings of science. She states: "Since we do not succeed in fleeing it let us therefore try to look the truth in the face. Let us try to assume our fundamental ambiguity. It is in the knowledge of the genuine conditions of our life that we must draw our strength to live and our reason for acting.".5 Other continental philosophers suggest that concepts such as life nature and sex are ambiguous.6 Recently Corey Anton has argued that we cannot be certain what is separate from or unified with something else: language he asserts divides what is not in fact separate.7 Following Ernest Becker he argues that the desire to 'authoritatively disambiguate' the world and existence has led to numerous ideologies and historical events such as genocide. On this basis he argues that ethics must focus on 'dialectically integrating opposites' and balancing tension rather than seeking a priori validation or certainty. Like the existentialists and phenomenologists he sees the ambiguity of life as the basis of creativity.8 In literature and rhetoric ambiguity can be a useful tool. Groucho Marxs classic joke depends on a grammatical ambiguity for its humor for example: "Last night I shot an elephant in my pajamas. How he got in my pajamas Ill never know". Ambiguity can also be used as a comic device through a genuine intention to confuse as does Magic: The Gathering's Unhinged Ambiguity which makes puns with homophones mispunctuation and run-ons: "Whenever a player plays a spell that counters a spell that has been played or a player plays a spell that comes into play with counters that player may counter the next spell played or put an additional counter on a permanent that has already been played but not countered". Songs and poetry often rely on ambiguous words for artistic effect as in the song title "Dont It Make My Brown Eyes Blue" (where "blue" can refer to the color or to sadness). In narrative ambiguity can be introduced in several ways: motive plot character. F. Scott Fitzgerald uses the latter type of ambiguity with notable effect in his novel The Great Gatsby. All religions debate the orthodoxy or heterodoxy of ambiguity. Christianity and Judaism employ the concept of paradox synonymously with 'ambiguity'. Ambiguity within Christianity9 (and other religions) is resisted by the conservatives and fundamentalists who regard the concept as equating with 'contradiction'. Non-fundamentalist Christians and Jews endorse Rudolf Otto's description of the sacred as 'mysterium tremendum et fascinans' the awe-inspiring mystery which fascinates humans. Metonymy involves the use of the name of a subcomponent part as an abbreviation or jargon for the name of the whole object (for example "wheels" to refer to a car or "flowers" to refer to beautiful offspring an entire plant or a collection of blooming plants). In modern vocabulary critical semiotics10 metonymy encompasses any potentially ambiguous word substitution that is based on contextual contiguity (located close together) or a function or process that an object performs such as "sweet ride" to refer to a nice car. Metonym miscommunication is considered a primary mechanism of linguistic humour.11 Psychology and management In sociology and social psychology the term "ambiguity" is used to indicate situations that involve uncertainty. An increasing amount of research is concentrating on how people react and respond to ambiguous situations. Much of this focuses on ambiguity tolerance. A number of correlations have been found between an individuals reaction and tolerance to ambiguity and a range of factors. Apter and Desselles (2001)12 for example found a strong correlation with such attributes and factors like a greater preference for safe as opposed to risk-based sports a preference for endurance-type activities as opposed to explosive activities a more organized and less casual lifestyle greater care and precision in descriptions a lower sensitivity to emotional and unpleasant words a less acute sense of humor engaging a smaller variety of sexual practices than their more risk-comfortable colleagues a lower likelihood of the use of drugs pornography and drink a greater likelihood of displaying obsessional behavior. In the field of leadership David Wilkinson (2006)13 found strong correlations between an individual leader's reaction to ambiguous situations and the Modes of Leadership they use the type of creativity Kirton (2003)14 and how they relate to others. Music In music pieces or sections which confound expectations and may be or are interpreted simultaneously in different ways are ambiguous such as some polytonality polymeter other ambiguous meters or rhythms and ambiguous phrasing or (Stein 2005 p. 79) any aspect of music. The music of Africa is often purposely ambiguous. To quote Sir Donald Francis Tovey (1935 p. 195) Theorists are apt to vex themselves with vain efforts to remove uncertainty just where it has a high aesthetic value. Visual art The Necker cube an ambiguous image. In visual art certain images are visually ambiguous such as the Necker cube which can be interpreted in two ways. Perceptions of such objects remain stable for a time then may flip a phenomenon called multistable perception. The opposite of such ambiguous images are impossible objects. Pictures or photographs may also be ambiguous at the semantic level: the visual image is unambiguous but the meaning and narrative may be ambiguous: is a certain facial expression one of excitement or fear for instance Constructed language Some languages have been created with the intention of avoiding ambiguity especially lexical ambiguity. Lojban and Loglan are two related languages which have been created with this in mind focusing chiefly on syntactic ambiguity as well. The languages can be both spoken and written. These languages are intended to provide a greater technical precision over big natural languages although historically such attempts at language improvement have been criticized. Languages composed from many diverse sources contain much ambiguity and inconsistency. The many exceptions to syntax and semantic rules are time-consuming and difficult to learn. Mathematical notation Mathematical notation widely used in physics and other sciences avoids many ambiguities compared to expression in natural language. However for various reasons several lexical syntactic and semantic ambiguities remain. Names of functions The ambiguity in the style of writing a function should not be confused with a multivalued function which can (and should) be defined in a deterministic and unambiguous way. Several special functions still do not have established notations. Usually the conversion to another notation requires to scale the argument and/or the resulting value; sometimes the same name of the function is used causing confusions. Examples of such underestablished functions: Sinc function Elliptic integral of the Third Kind; translating elliptic integral form MAPLE to Mathematica one should replace the second argument to its square see Talk:Elliptic integral#Listofnotations; dealing with complex values this may cause problems. Exponential integral15 page 228 http://www.math.sfu.ca/cbm/aands/page228.htm Hermite polynomial15 page 775 http://www.math.sfu.ca/cbm/aands/page775.htm Expressions Ambiguous expressions often appear in physical and mathematical texts. It is common practice to omit multiplication signs in mathematical expressions. Also it is common to give the same name to a variable and a function for example . Then if one sees there is no way to distinguish does it mean multiplied by or function evaluated at argument equal to . In each case of use of such notations the reader is supposed to be able to perform the deduction and reveal the true meaning. Creators of algorithmic languages try to avoid ambiguities. Many algorithmic languages (C++ MATLAB Fortran) require the character * as symbol of multiplication. The language Mathematica allows the user to omit the multiplication symbol but requires square brackets to indicate the argument of a function; square brackets are not allowed for grouping of expressions. Fortran in addition does not allow use of the same name (identifier) for different objects for example function and variable; in particular the expression ff(x) is qualified as an error. The order of operations may depend on the context. In most programming languages the operations of division and multiplication have equal priority and are executed from left to right. Until the last century many editorials assumed that multiplication is performed first for example is interpreted as ; in this case the insertion of parentheses is required when translating the formulas to an algorithmic language. In addition it is common to write an argument of a function without parenthesis which also may lead to ambiguity. Sometimes one uses italics letters to denote elementary functions. In the scientific journal style the expression means product of variables and although in a slideshow it may mean . Comma in subscripts and superscripts sometimes is omitted; it is also ambiguous notation. If it is written the reader should guess from the context does it mean a single-index object evaluated while the subscript is equal to product of variables and or it is indication to a three-valent tensor. The writing of instead of may mean that the writer either is stretched in space (for example to reduce the publication fees or aims to increase number of publications without considering readers. The same may apply to any other use of ambiguous notations. Subscripts are also used to denote the argument to a function as in Fx. Examples of potentially confusing ambiguous mathematical expressions which could be understood to mean either or . In addition sin2(x) may mean sin(sin(x)) as exp2(x) means exp(exp(x)) (see tetration). which by convention means though it might be thought to mean since means . which arguably should mean but would commonly be understood to mean Notations in quantum optics and quantum mechanics It is common to define the coherent states in quantum optics with and states with fixed number of photons with . Then there is an "unwritten rule": the state is coherent if there are more Greek characters than Latin characters in the argument and photon state if the Latin characters dominate. The ambiguity becomes even worse if is used for the states with certain value of the coordinate and means the state with certain value of the momentum which may be used in books on quantum mechanics. Such ambiguities easy lead to confusions especially if some normalized adimensional dimensionless variables are used. Expression may mean a state with single photon or the coherent state with mean amplitude equal to 1 or state with momentum equal to unity and so on. The reader is supposed to guess from the context. Ambiguous terms in physics and mathematics Some physical quantities do not yet have established notations; their value (and sometimes even dimension as in the case of the Einstein coefficients) depends on the system of notations. Many terms are ambiguous. Each use of an ambiguous term should be preceded by the definition suitable for a specific case. Just like Ludwig Wittgenstein states in Tractatus Logico-Philosophicus: "... Only in the context of a proposition has a name meaning." 16 A highly confusing term is gain. For example the sentence "the gain of a system should be doubled" without context means close to nothing. It may mean that the ratio of the output voltage of an electric circuit to the input voltage should be doubled. It may mean that the ratio of the output power of an electric or optical circuit to the input power should be doubled. It may mean that the gain of the laser medium should be doubled for example doubling the population of the upper laser level in a quasi-two level system (assuming negligible absorption of the ground-state). The term intensity is ambiguous when applied to light. The term can refer to any of irradiance luminous intensity radiant intensity or radiance depending on the background of the person using the term. Also confusions may be related with the use of atomic percent as measure of concentration of a dopant or resolution of an imaging system as measure of the size of the smallest detail which still can be resolved at the background of statistical noise. See also Accuracy and precision and its talk. The Berry paradox arises as a result of systematic ambiguity in the meaning of terms such as "definable" or "nameable". Terms of this kind give rise to vicious circle fallacies. Other terms with this type of ambiguity are: satisfiable true false function property class relation cardinal and ordinal.17 Mathematical interpretation of ambiguity The Necker cube and impossible cube an underdetermined and overdetermined object respectively. In mathematics and logic ambiguity can be considered to be an underdetermined system (of equations or logic) for example X Y leaves open what the value of X is while its opposite is a self-contradiction also called inconsistency paradoxicalness or oxymoron in an overdetermined system such as X 2X 3 which has no solution see also underdetermination. Logical ambiguity and self-contradiction is analogous to visual ambiguity and impossible objects such as the Necker cube and impossible cube or many of the drawings of M. C. Escher.18 Pedagogic use of ambiguous expressions Ambiguity can be used as a pedagogical trick to force students to reproduce the deduction by themselves. Some textbooks19 give the same name to the function and to its Fourier transform: . Rigorously speaking such an expression requires that ; even if function is a self-Fourier function the expression should be written as ; however it is assumed that the shape of the function (and even its norm ) depend on the character used to denote its argument. If the Greek letter is used it is assumed to be a Fourier transform of another function The first function is assumed if the expression in the argument contains more characters or than characters and the second function is assumed in the opposite case. Expressions like or contain symbols and in equal amounts; they are ambiguous and should be avoided in serious deduction. See also Abbreviation Ambiguity tolerance Amphibology Decision problem Disambiguation Double entendre Essentially contested concept Fallacy Formal fallacy Golden hammer Imprecise language Informal fallacy Self reference Semantics Uncertainty Volatility uncertainty complexity and ambiguity Word sense disambiguation References "And do you see its long nose and chin At least they look exactly like a nose and chin that is don't they But they really are two of its legs. You know a Caterpillar has got quantities of legs: you can see more of them further down." Carroll Lewis. The Nursery "Alice". Dover Publications (1966) p27. Kroeger Paul (2005). Analysing Grammar: An Introduction. Cambridge: Cambridge University Press. pp. 2627. ISBN 978-0-521-01653-7.  Heidegger Martin. "The Origin of the Work of Art". Poetry Language Thought. Trans. Albert Hofstadter. NY: Harper Collins 1971 pg. 18. de Beauvoir Simone. The Ethics of Ambiguity. Trans. Bernard Frechtman. New York: Citadel Press 1976 1948 pg. 8. de Beauvoir Ethics pg. 9. Foucault Michel. The History of Sexuality An Introduction (Vol. 1). Trans Robert Hurley. New York: Vintage Books 1978. Anton Corey. Sources of Significance: Worldly Rejuvenation and Neo-Stoic Heroism. West Lafayette: Purdue University Press 2010 pg. 35-63. Anton Corey. "Authoritative Disambiguation"1. Professoranton 2009. Living With Ambiguity CSI: Sim8 Veale Tony (2003): "Metaphor and Metonymy: The Cognitive Trump-Cards of Linguistic Humor"2 in Motivational Styles in Everyday life: A guide to reversal Theory. M.J. Apter (ed) (2001) APA Books Wilkinson D.J. (2006) The Ambiguity Advantage: What great leaders are great at. New York Palgrave Macmillan. Kirton M.J. (2003)Adaption-Innovation: In the Context of Diversity and Change. Routledge. a b M.Abramovits I.Stegun. Handbook on mathematical functions Wittgenstein Ludwig (1999). Tractatus Logico-Philosophicus. Dover Publications Inc.. p. 39. ISBN 0-486-40445-5.  Russell/Whitehead Principia Mathematica Goldstein Laurence (1996). "Reflexivity Contradiction Paradox and M. C. Escher". Leonardo (The MIT Press) 29 (4): 299308. doi:10.2307/1576313. JSTOR 1576313  H. Haug S. Koch. Quantum Theory of the Optical and Electronic Properties of Semiconductors http://www.allbookstores.com/book/9812387560 External links Look up ambiguity in Wiktionary the free dictionary. Collection of Ambiguous or Inconsistent/Incomplete Statements Leaving out ambiguities when writing v d eFallacies of relevance General Absurdity  Accident  Ad nauseam  Argument from ignorance  Argument from silence  Argument to moderation  Argumentum ad populum  Base rate  Compound question  Evidence of absence  Invincible ignorance  Loaded question  Moralistic  Naturalistic  Non sequitur  Proof by assertion  Irrelevant conclusion  Special pleading  Straw man  Two wrongs make a right Appeals to emotion Fear  Flattery  Nature  Novelty  Pity  Ridicule  Children's interests  Invented Here  Island mentality  Not Invented Here  Repugnance  Spite Genetic fallacies Ad feminam  Ad hominem (Ad hominem tu quoque)  Appeal to accomplishment  Appeal to authority  Appeal to etymology  Appeal to motive  Appeal to novelty  Appeal to poverty  Appeals to psychology  Appeal to the stone  Appeal to tradition  Appeal to wealth  Association  Bulverism  Chronological snobbery  Ipse dixit (Ipse-dixitism)  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question  McNamara fallacy  Name calling  Nirvana fallacy  Rationalization (making excuses)  Red herring fallacy  Special pleading  Slothful induction Correlative-based fallacies False dilemma  Denying the correlative  Suppressed correlative Deductive fallacies Accident  Converse accident Inductive fallacies Sampling bias  Conjunction fallacy  False analogy  Hasty generalization  Misleading vividness  Overwhelming exception Vagueness and ambiguity Amphibology  Continuum fallacy  False precision  Slippery slope Equivocation Equivocation  False attribution  Fallacy of quoting out of context  Loki's Wager  No true Scotsman  Reification Questionable cause Animistic  Appeal to consequences  Argumentum ad baculum  Correlation does not imply causation (Cum hoc)  Gambler's fallacy and its inverse  Post hoc  Prescience  Regression  Single cause  Slippery slope  Texas sharpshooter  The Great Magnet  Unknown Root  Wrong direction List of fallacies  Other types of fallacy v d eLogic  Related 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