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Descriptivist theory of names is a view of the nature of the meaning and reference of proper names generally attributed to Gottlob Frege and Bertrand Russell. The theory consists essentially in the idea that the meanings (semantic contents) of names are identical to the descriptions associated with them by speakers, while their referents are determined to be the objects that satisfy these descriptions. In the 1970s, this theory came under strong attack from causal theorists such as Saul Kripke, Hilary Putnam and others. However, it has seen something of a revival in recent years, especially under the form of what are called two-dimensional semantic theories. This latter trend is exemplified by the theories of David Chalmers, among others. ==The descriptive theory and its merits== A simple descriptivist theory of names can be thought of as follows: for every proper name ''p'', there is some collection of descriptions ''D'' associated with ''p'' that constitute the meaning of ''p''. For example, the descriptivist may hold that the proper name ''Saul Kripke'' is synonymous with the collection of descriptions such as # the man who wrote ''Naming and Necessity'' # a person who was born on November 13, 1940 in Bay Shore, New York # the son of a leader of Beth El Synagogue in Omaha, Nebraska : etc ... The descriptivist takes the meaning of the name ''Saul Kripke'' to be that collection of descriptions and takes the referent of the name to be the thing that satisfies all or most of those descriptions. A simple descriptivist theory may further hold that the meaning of a sentence ''S'' that contains ''p'' is given by the collection of sentences produced by replacing each instance of ''p'' in ''S'' with one of the descriptions in ''D''. So, the sentence such as "Saul Kripke stands next to a table" has the same meaning as the following collection of sentences: # The man who wrote ''Naming and Necessity'' stands next to a table. # A person who was born on November 13, 1940 in Bay Shore, New York stands next to a table. # The son of a leader of Beth El Synagogue in Omaha, Nebraska stands next to a table. : etc ... A type of simple descriptivism was originally formulated by Frege in reaction to problems that confronted the predominant theory of names of the 19th century due to John Stuart Mill. Mill's theory is often referred to as the "Fido"-Fido theory because it suggests that the meaning of a proper name is simply its bearer in the external world (its direct referent, as we would say now). There are several significant problems with this proposal, however. First, it does not explain how and why names without bearers can still be meaningful even though they have no reference. Take the following two sentences: *(A) There is no Santa Claus. *(B) Santa Claus does not exist. According to Mill's theory, these sentences must be meaningless. This is the case because sentences obtain their meanings compositionally and one of the main constituents of these sentences--the predicate in the first and the subject in the second-- is meaningless. But such sentences obviously seem perfectly meaningful to most human beings and they are used in everyday language to express true statements about reality. More evidence for the meaningfulness of sentences such as the ones presented above consists in the fact that they are ''synonymous.'' Furthermore, the conjunction of (A) and (B): *(C) There is no Santa Claus and Santa Claus does not exist. is redundant. While the following sentence: *(D) Santa Claus does not exist but there is a Santa Claus. is contradictory. Frege set about to resolve this problem, among others, with his famous distinction between sense and reference. In the case of proper names, the sense (or Sinn) of a term consists in the (usually) definite description that speakers associate with it. Thus, the sense of the proper name Santa Claus may be something like “The benevolent, bearded man that brings gifts to children at Christmas time.” This sense of a term is objective (it is an abstract object) for Frege and is definitely not to be confused with its subjective representation in the mind of each individual speaker. However, a proper name can have more than one sense associated with it. The name Santa Claus could be associated with “The benevolent, bearded man…” as well as with the description “The fat, old gentleman with the red cape…” In Frege, the relationship between sense and representation is one of determination: the references of names are determined by their senses as modes of presentation. If referents are objects in the external world, then senses are simply different ways of grasping the same object through different means. An object need not necessarily have a referent either in the external world or in the realm of abstract objects but it will always have a sense in the objective realm of thought for Frege. Hence, problems concerning the meaningfulness of sentences like (A) and (B) as well as the types of problems associated with sentences (C) and (D) above do not arise on this view. Russell’s approach is somewhat different. First of all, Russell makes an important distinction between what he calls “ordinary” proper names and “logically” proper names. Logically proper names are indexicals such as ''this'' and ''that'', which directly refer (in a Millian sense) to sense-data or other objects of immediate acquaintance. For Russell, ordinary proper names are ''abbreviated definite descriptions.'' Here definite description refers again to the type of formulation “The…” which was used above to describe Santa Claus as “the benevolent, bearded….’’ According to Russell, the name “Aristotle” is just a sort of shorthand for a definite description such as “The last great philosopher of ancient Greece” or “The teacher of Alexander the great” or some conjunction of two or more such descriptions. Now, according to Russell’s theory of definite descriptions, such descriptions must, in turn, be reduced, to a certain very specific logical form of existential generalization as follows: *"The king of France is bald". becomes * This says that there is exactly one object ‘’x’’ such that ‘’x’’ is King of France and ‘’x’’ is bald. Notice that this formulation is entirely general: it says that there is some x out in the world that satisfies the description, but does not specify which one thing ‘’x’’ refers to. Indeed, for Russell, definite descriptions (and hence names) have no reference at all and their meanings (senses in the Fregean sense) are just the truth conditions of the logical forms illustrated above. This is made clearer by Russell’s example involving ‘’Bismarck’’: *(G) ”The Chancellor of Germany...” In this case, Russell suggests that only Bismarck himself can be in a relation of acquaintance such that the man himself enters into the proposition expressed by the sentence. For any other than Bismarck, the only relation that is possible with such a proposition is through its descriptions. Bismarck could never have existed and the sentence (G) would still be meaningful because of its general nature described by the logical form underlying the sentence. Notwithstanding these differences however, descriptivism and the descriptive theory of proper names came to be associated with both the views of Frege and Russell and both address the general problems (names without bearers, Frege’s puzzles concerning identity and substitution in contexts of intentional attitude attributions) in a similar manner. Another problem for Millianism is Frege’s famous puzzles concerning the identity of co-referring terms. For example: *(V) ”Hesperus is Phosphorus.” In this case, both terms (“Hesperus” and “Phosphorus”) refer to the same entity: Venus. The Millian theory would predict that this sentence is trivial, since meaning is just reference and “Venus is Venus” is not very informative. Suppose, however, that someone did not know that Hesperus and Phosphorus both referred to Venus. Then it is at least arguable that the sentence (V) is an attempt to inform someone of just this fact. Other problems for Millianism are those of negative existentials (e.g., “Batman does not exist”) and statements such as “Fred believes that Cicero, but not Tully, was Roman.” 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「descriptivist theory of names」の詳細全文を読む スポンサード リンク
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