Tautology logic, in formal logic, a statement that is true in every possible interpretation. The expression raze to the ground is a tautology, since the word raze includes the notion to the ground. In propositional logic, there is no distinction between a tautology and a logically valid formula. If assuming a false sentence prevents us from arriving at any coherent truth. This is the logical notion of tautology, which is very different from the way the term tautology is used in stylistics. Tautological statement definition of tautological statement. In simple words, it is expressing the same thing, an idea, or saying, two or more times. Essentially, a tautology expresses the same thing, idea, or saying repeatedly. Tautology definition of tautology by the free dictionary.
Tautology is useless restatement, or saying the same thing twice using different words. The opposite of a tautology is a contradiction, a formula which is always false. For example, the statement that 2 2 would be a logical tautology. A tautology is a formula which is always true that is, it is true for every assignment of truth values to its simple components. Truthtables,tautologies,andlogicalequivalences mathematicians normally use a twovalued logic. Definition of tautology from our glossary of english linguistic and grammatical terms containing explanations and crossreferences to other relevant english grammar terms. Download fulltext pdf tautology and testability in economics article pdf available in philosophy of the social sciences 11. In propositional logic, a tautology from the greek word. Tautology definition, needless repetition of an idea, especially in words other than those of the immediate context, without imparting additional force or clearness, as in widow woman.
Often, repetition is meaningful or poetic and may emphasize an important aspect. Tautology rule of inference, a rule of replacement for logical expressions. Meaning of tautology in a sentence words in sentences. Meaning of tautology in a sentence by wordsmith published july 30, 2016 updated february 20, 2019 definition. Tautology definition, needless repetition of an idea, especially in words other than those of the immediate context, without imparting additional force. Tautology definition and meaning collins english dictionary. Tautology in math definition, logic, truth table and examples. Since it is magical, it can of course only take refuge behind the argument of authority. A tautology is a statement that is always true, no matter what.
Tautologies definition and meaning collins english. Tautology definition of tautology by merriamwebster. Tautology article about tautology by the free dictionary. Tautology is the repetitive use of phrases or words that have similar meanings. Tautology is the use of different words to say the same thing twice in the same. Mar 01, 2020 tautology countable and uncountable, plural tautologies uncountable redundant use of words, a pleonasm, an unnecessary and tedious repetition. Tautological definition of tautological by merriamwebster. The notion was first developed in the early 20th century by the american philosopher charles sanders peirce, and the term itself was introduced by the austrianborn british philosopher ludwig wittgenstein.
Redundancy disambiguation tautological disambiguation tautonym, a scientific name of a species in which both parts of the name have the same spelling. The word tautology is derived from a greek word where tauto means same and logy means logic. Its only a tautology is you pretend life and niches dont have distinguishable properties and that a niche cant be populated. Tautology is the repetitive use of words or phrases which have similar meanings to one another. A tautology is a compound statement which is true for every value of the individual statements. Tautology meaning in the cambridge english dictionary.
No matter what the individual parts are, the result is a true statement. This might involve, for example, taking the presence of an effect to argue for the presence of a cause, which is then claimed to bring. The philosopher ludwig wittgenstein first applied the term to propositional logic in. Tautological definition is involving or containing rhetorical tautology. Tautology and pleonasm are not consistently differentiated in literature. Redundancy disambiguation tautological disambiguation tautonym, a scientific name of a species in. May 27, 2018 tautological comparative more tautological, superlative most tautological of, relating to, or using tautology using repetition or excessive wordiness. Within logic, though, a tautology is just an inherently true statement. Anaphora is the repetition of a certain phrase at the beginning of successive sentences or phrases. A contradiction is a proposition that is always false. In other words, it is saying the same thing twice in different words. For examples of meaningful repetition, consider anaphora and epistrophe. Information and translations of tautology in the most comprehensive dictionary definitions resource on the web. A compound statement is made with two more simple statements by using some conditional words such as and, or, not.
A contingency is a proposition that is neither a tautology nor a contradiction. A statement that is always true by a virtue of its components. This tautology, called the law of excluded middle, is a direct consequence of our basic assumption that a proposition is a statement that is either true or false. Tautology logic simple english wikipedia, the free. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Tautology rhetorical devices literature ultius glossary. Click the button below to get instant access to these worksheets for use in the classroom or at a home.
If you construct a truth table for a statement and all of the column values for the statement are. Speedy sprint is a tautology because sprint already means speedy running. Its only a tautology is you pretend life and niches dont have distinguishable properties and that a niche cant be populated an ancient time frame. It refers to a redundant logic wherein a principle is restated or is evident in its expression. Tautologies definition and meaning collins english dictionary. Tautology definition is needless repetition of an idea, statement, or word. This page includes examples of tautology that are mistakes e. Tautology is a style or logic where you say something by repeating it andor saying it in a different way twice. Tautology is the needless repetition of a single concept. The definition of tautology can be extended to sentences in predicate logic, which may contain quantifiers, unlike sentences of propositional logic.
Tautology language, redundant statements in literature and rhetoric tautology logic, in formal logic, a statement that is true in every possible interpretation tautology rule of inference, a rule of replacement for logical expressions see also. Tautology is an unwanted repetition, but not all repetition is pointless. Needless repetition of the same sense in different words. For example, formulae in maths are tautological, because they always hold true for any values. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext.
A tautology in math and logic is a compound statement premise and conclusion that always produces truth. Therefore, evolution by natural selection is a tautology a circular definition. Tautological statement synonyms, tautological statement pronunciation, tautological statement translation, english dictionary definition of tautological statement. Tautology, contradiction and contingency definition tautology.
Tautology is a type of logic construct that can be applied in it. Tautology, in logic, a statement so framed that it cannot be denied without inconsistency. A compound statement is made with two more simple statements by using some conditional words such as and, or, not, if, then, and if and only if. This might involve, for example, taking the presence of an effect. Like pleonasm, tautology is often considered a fault of style when unintentional.
The opposite of a tautology is a contradiction or a fallacy, which is always false. The word tautology is derived from the greek word tauto, meaning the same, and logos, meaning a word or an idea. Like you said, a tautology in sentence logic, where the internal structure of sentences does not matter, it is a sentence that cannot be falsified by any assignment of truth values to the component sentences. If you are given any statement or argument, you can determine if it is a tautology by constructing a truth table for the statement and looking at. Mar 10, 2019 tautology is this verbal device which consists in defining like by like. In literary criticism and rhetoric, a tautology is a statement which repeats an idea, using nearsynonymous morphemes, words or phrases, saying the same thing twice. A tautology states the same thing twice in a slightly differen the word denote is used as a verb which means to be a mark or connote is used as a verb meaning to imply or suggest an idea. In logic, however, a tautology is defined as a statement that excludes no logical possibilitieseither it is raining or it is not raining.
Listen to the audio pronunciation in the cambridge english dictionary. The notion was first developed in the early 20th century by the american philosopher charles sanders peirce, and the term itself was introduced by the austrian. D is a tautology b d b b v d d f a tautology will never be false, so if we plug in a value of f for the main connective and get a coherent truth assignment for b and d, we know that the sentence can be false, and so cannot be a tautology. There are many reasons people use tautology in both everyday discussion and poetry, research papers, prose, and song lyrics. In common parlance, an utterance is usually said to be tautologous if it contains a redundancy and says the same thing twice over in different wordse. This is maybe a weakness, because of the simplicity of sentence calculus.
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