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Extensional Fault Array Clarke Head
In any of several fields of study that treat the use of signs — for example, in linguistics, logic, mathematics, semantics, semiotics, and philosophy of language — an extensional context (or transparent context) is a syntactic environment in which a sub-sentential expression ''e'' can be replaced by an expression with the same extension and without affecting the truth-value of the sentence as a whole. Extensional contexts are contrasted with opaque contexts where truth-preserving substitutions are not possible. Take the case of Clark Kent, who is secretly Superman. Suppose that Lois Lane fell out of a window and Superman caught her. Thus the sentence "Superman caught Lois Lane" is true. Because this sentence is an extensional context, the sentence "Clark Kent caught Lois Lane" is also true. Anybody that Superman caught, Clark Kent caught. In opposition to extensional contexts are intensional contexts (which can involve modal operators and modal logic), where terms cannot be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linguistics
Linguistics is the scientific study of language. The areas of linguistic analysis are syntax (rules governing the structure of sentences), semantics (meaning), Morphology (linguistics), morphology (structure of words), phonetics (speech sounds and equivalent gestures in sign languages), phonology (the abstract sound system of a particular language, and analogous systems of sign languages), and pragmatics (how the context of use contributes to meaning). Subdisciplines such as biolinguistics (the study of the biological variables and evolution of language) and psycholinguistics (the study of psychological factors in human language) bridge many of these divisions. Linguistics encompasses Outline of linguistics, many branches and subfields that span both theoretical and practical applications. Theoretical linguistics is concerned with understanding the universal grammar, universal and Philosophy of language#Nature of language, fundamental nature of language and developing a general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modal Operator
A modal connective (or modal operator) is a logical connective for modal logic. It is an operator which forms propositions from propositions. In general, a modal operator has the "formal" property of being non- truth-functional in the following sense: The truth-value of composite formulae sometimes depend on factors other than the actual truth-value of their components. In the case of alethic modal logic, a modal operator can be said to be truth-functional in another sense, namely, that of being sensitive only to the distribution of truth-values across possible worlds, actual or not. Finally, a modal operator is "intuitively" characterized by expressing a modal attitude (such as necessity, possibility, belief, or knowledge) about the proposition to which the operator is applied. Syntax for modal operators The syntax rules for modal operators \Box and \Diamond are very similar to those for universal and existential quantifiers; In fact, any formula with modal operators \Box and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philosophy Of Language
Philosophy of language refers to the philosophical study of the nature of language. It investigates the relationship between language, language users, and the world. Investigations may include inquiry into the nature of Meaning (philosophy), meaning, intentionality, reference, the constitution of sentences, concepts, learning, and thought. Gottlob Frege and Bertrand Russell were pivotal figures in analytic philosophy's "linguistic turn". These writers were followed by Ludwig Wittgenstein (''Tractatus Logico-Philosophicus''), the Vienna Circle, Logical positivism, logical positivists, and Willard Van Orman Quine. History Ancient philosophy In the West, inquiry into language stretches back to the 5th century BC with philosophers such as Socrates, Plato, Aristotle, and the Stoics. Linguistic speculation predated systematic descriptions of grammar which emerged in India and in Greece. In the dialogue ''Cratylus (dialogue), Cratylus'', Plato considered the question of whether ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propositional Attitude
A propositional attitude is a mental state held by an agent or organism toward a proposition. In philosophy, propositional attitudes can be considered to be neurally realized, causally efficacious, content-bearing internal states (personal principles/values). Linguistically, propositional attitudes are denoted by a verb (e.g. ''believed'') governing an embedded "that" clause, for example, 'Sally believed that she had won'. Propositional attitudes are often assumed to be the fundamental units of thought and their contents, being propositions, are true or false from the perspective of the person. An agent can have different propositional attitudes toward the same proposition (e.g., "''S'' believes that her ice-cream is cold," and "''S'' fears that her ice-cream is cold"). Propositional attitudes have directions of fit: some are meant to reflect the world, others to influence it. One topic of central concern is the relation between the modalities of assertion and belief, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opaque Context
An opaque context or referentially opaque context is a linguistic context in which it is not always possible to substitute "co-referential" expressions (expressions referring to the same object) without altering the truth of sentences. The expressions involved are usually grammatically singular terms. So, substitution of co-referential expressions into an opaque context does not always preserve truth. For example, "Lois believes x is a hero" is an opaque context because "Lois believes Superman is a hero" is true while "Lois believes Clark Kent is a hero" is false, even though 'Superman' and 'Clark Kent' are co-referential expressions. Usage The term is used in philosophical theories of reference, and is to be contrasted with referentially transparent context. In the opaque case, "Mary believes that Cicero is a great orator" gives rise to an opaque context; although Cicero was also called 'Tully',Tully is anglicised historic name from Tullius, source: we can't simply substitu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intensional Logic
Intensional logic is an approach to predicate logic that extends first-order logic, which has quantifiers that range over the individuals of a universe (''extensions''), by additional quantifiers that range over terms that may have such individuals as their value (''intensions''). The distinction between intensional and extensional entities is parallel to the distinction between sense and reference. Overview Logic is the study of proof and deduction as manifested in language (abstracting from any underlying psychological or biological processes). Logic is not a closed, completed science, and presumably, it will never stop developing: the logical analysis can penetrate into varying depths of the language (sentences regarded as atomic, or splitting them to predicates applied to individual terms, or even revealing such fine logical structures like modal, temporal, dynamic, epistemic ones). In order to achieve its special goal, logic was forced to develop its own formal tools ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensionalism
Extensionalism, in the philosophy of language, in logic and semantics, is the view that all languages or at least all scientific languages should be extensional. It has been described as the default option for the scientism in the nineteenth century and the result of the application of empiricistic inductive methodology to the problem of semantics. Concept The idea of extensionality is considered a form of reductionism with the way it holds that every meaningful and declarative sentence is equivalent to some extensional sentence. Rudolf Carnap (in his earlier work) and Willard Van Orman Quine were prominent proponents of this view. Carnap's thesis of extensionality is associated with the relation between extensional and nonextensional languages. According to the thinker, the former has simpler structures and constitutive rules than the latter so that it is possible to discuss exhaustively all scientific phenomena when using extensional language. The idea put forward by Richard M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensional Definition
In logic, extensional and intensional definitions are two key ways in which the objects, concepts, or referents a term refers to can be defined. They give meaning or denotation to a term. An intensional definition gives meaning to a term by specifying necessary and sufficient conditions for when the term should be used. An extensional definition gives meaning to a term by specifying every object that falls under the definition of the term in question. For example, in set theory one would extensionally define the set of square numbers as , while an intensional definition of the set of the square numbers could be . Intensional definition An intensional definition gives meaning to a term by specifying necessary and sufficient conditions for when the term should be used. In the case of nouns, this is equivalent to specifying the properties that an object needs to have in order to be counted as a referent of the term. For example, an intensional definition of the word "bache ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
De Dicto And De Re
''De dicto'' and ''de re'' are two phrases used to mark a distinction in intensional statements, associated with the intensional operators in many such statements. The distinction is used regularly in analytical metaphysics and in philosophy of language. The literal translation of the phrase ''de dicto'' is "about what is said", whereas ''de re'' translates as "about the thing". The original meaning of the Latin locutions may help to elucidate the living meaning of the phrases, in the distinctions they mark. The distinction can be understood by examples of intensional contexts of which three are considered here: a context of thought, a context of desire, and a context of modality. Context of thought There are two possible interpretations of the sentence "Peter believes someone is out to get him": On the ''de dicto'' interpretation, 'someone' is unspecific and Peter suffers a general paranoia; he believes that it is true that a person is out to get him, but does not necessaril ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propositional Attitude
A propositional attitude is a mental state held by an agent or organism toward a proposition. In philosophy, propositional attitudes can be considered to be neurally realized, causally efficacious, content-bearing internal states (personal principles/values). Linguistically, propositional attitudes are denoted by a verb (e.g. ''believed'') governing an embedded "that" clause, for example, 'Sally believed that she had won'. Propositional attitudes are often assumed to be the fundamental units of thought and their contents, being propositions, are true or false from the perspective of the person. An agent can have different propositional attitudes toward the same proposition (e.g., "''S'' believes that her ice-cream is cold," and "''S'' fears that her ice-cream is cold"). Propositional attitudes have directions of fit: some are meant to reflect the world, others to influence it. One topic of central concern is the relation between the modalities of assertion and belief, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modal Logic
Modal logic is a kind of logic used to represent statements about Modality (natural language), necessity and possibility. In philosophy and related fields it is used as a tool for understanding concepts such as knowledge, obligation, and causality, causation. For instance, in epistemic modal logic, the well-formed_formula, formula \Box P can be used to represent the statement that P is known. In deontic modal logic, that same formula can represent that P is a moral obligation. Modal logic considers the inferences that modal statements give rise to. For instance, most epistemic modal logics treat the formula \Box P \rightarrow P as a Tautology_(logic), tautology, representing the principle that only true statements can count as knowledge. However, this formula is not a tautology in deontic modal logic, since what ought to be true can be false. Modal logics are formal systems that include unary operation, unary operators such as \Diamond and \Box, representing possibility and necessi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lois Lane
Lois Lane is a fictional character appearing in American comic books published by DC Comics. Created by writer Jerry Siegel and artist Joe Shuster, she first appeared in ''Action Comics'' Action Comics 1, #1 (June 1938). Lois is an award-winning journalist for the Metropolis (comics), Metropolis newspaper the ''Daily Planet'' and the primary Superman and Lois Lane, love interest of the superhero Superman and his alter ego, Clark Kent. In DC continuity, she is also his wife and the mother of their son, Jon Kent (DC Comics), Jon Kent, the newest Superboy in the DC Universe. Lois's physical appearance was originally based on Joanne Siegel, Joanne Carter, a model hired by Joe Shuster. Jerry Siegel took her name from actress Lola Lane, while her character was inspired by actress Glenda Farrell's portrayal of the fictional reporter Torchy Blane in a series of 1930s self-titled films. Depictions of the character have varied spanning the comics and other media adaptations. The original ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
