Theory of descriptions
Encyclopedia
The theory of descriptions is the philosopher Bertrand Russell
's most significant contribution to the philosophy of language
. It is also known as Russell's Theory of Descriptions (commonly abbreviated as RTD). In short, Russell argued that the syntactic form of descriptions (phrases that took the form of "The aardvark" and "An aardvark") is misleading, as it does not correlate their logical and/or semantic architecture. While descriptions may seem fairly uncontroversial phrases, Russell argued that providing a satisfactory analysis of the linguistic and logical properties of a description is vital to clarity in important philosophical debates, particularly in semantic arguments, epistemology and metaphysics. It has been argued, for example, that RTD largely underpinned Russell's theory of sense-data.
Since the first development of the theory in Russell's 1905 paper "On Denoting
", RTD has been hugely influential and well-received within the philosophy of language. However, it has not been without its critics. In particular, the philosophers P. F. Strawson
and Keith Donnellan
have given notable, well known criticisms of the theory. Most recently, RTD has been defended by various philosophers and even developed in promising ways to bring it into harmony with generative grammar
in Noam Chomsky
's sense, particularly by Stephen Neale
. Such developments have themselves been criticized, and debate continues.
Indefinite descriptions comprise Russell's third group. Descriptions most frequently appear in the standard subject-predicate form.
Russell put forward his theory of descriptions in order to solve a number of problems in the philosophy of language. The two major problems are (1) co-referring expressions and (2) non-referring expressions. The problem of co-referring expressions originated primarily with Gottlob Frege
as the problem of informative identities. For example, if the morning star and the evening star are the same planet in the sky (indeed they are), how is it that someone can think that the morning star rises in the morning but the evening star does not? . This is apparently problematic because although the two expressions seem to denote the same thing, one cannot substitute one for the other, which one ought to be able to do with identical or synonymous expressions. This is even further complicated as both the Morning Star and Evening Star are also the planet Venus
.
The problem of non-referring expressions is that certain expressions that are meaningful do not truly refer to anything. For example, by "any dog is annoying" it is not meant that there is a particular individual dog, namely any dog, that has the property of being annoying(similar considerations go for "some dog", "every dog", "a dog", and so on). Likewise, by "the current Emperor of Germany is gray" it is not meant that there is some individual, namely the current Emperor of Germany , who has the property of being gray; Germany is no longer a monarchy, so there is currently no Emperor. Thus, what Russell wants to avoid is admitting mysterious non-existent entities into his ontology
. Furthermore, the law of the excluded middle requires that one of the following propositions, for example, must be true: either "the current Emperor of Germany is gray" or "it is not the case that the current Emperor of Germany is gray". Normally, propositions of the subject-predicate form are said to be true if and only if the subject is in the [extension] of the predicate. But, there is currently no Emperor of Germany. So, since the subject does not exist, it is not in the extension of either predicate (it is not on the list of gray people or non-gray people). Thus, it appears that this is a case in which the law of excluded middle is violated, which is also an indication that something has gone wrong.
Thus, a definite description (of the general form 'the F is G') becomes the following existentially quantified phrase in classic symbolic logic (where 'x' and 'y' are variables and 'F' and 'G' are predicates - in the example above, F would be "is an emperor of Germany", and G would be "is gray"):
Informally, this reads as follows: something exists with the property F, there is only one such thing, and this unique thing also has the property G.
This analysis, according to Russell, solves the two problems noted above as related to definite descriptions:
Russell says that all propositions in which the Emperor of Germany has a primary occurrence are false. The denials of such propositions are true, but in these cases the Emperor of Germany has a secondary occurrence (the truth value of the proposition is not a function of the truth of the existence of the Emperor of Germany).
Thus, an indefinite description (of the general form 'an D is A') becomes the following existentially quantified phrase in classic symbolic logic (where 'x' and 'y' are variables and 'D' and 'A' are predicates):
Informally, this reads as follows: there is something such that it is D and A.
This analysis, according to Russell, solves the second problem noted above as related to indefinite descriptions. Since the phrase "some dog is annoying" is not a referring expression, according to Russell's theory, it need not refer to a mysterious non-existent entity. Furthermore, the law of excluded middle need not be violated (i.e. it remains a law), because "some dog is annoying" comes out true: there is a thing that is both a dog and annoying. Thus, Russell's theory seems to be a better analysis insofar as it solves several problems.
argued that Russell had failed to correctly represent what one means when one says a sentence in the form of "the current Emperor of Germany is gray." According to Strawson, this sentence is not contradicted by "No one is the current Emperor of Germany", for the former sentence contains not an existential assertion, but attempts to use "the current Emperor of Germany" as a referring (or denoting) phrase. Since there is no current Emperor of Germany, the phrase fails to refer to anything, and so the sentence is neither true nor false.
, there are two distinct ways we may use a definite description such as "the current Emperor of Germany is gray", and thus makes his distinction between the referential and the attributive use of a definite description. He argues that both Russell and Strawson make the mistake of attempting to analyze sentences removed from their context. We can mean different and distinct things while using the same sentence in different situations.
For example, suppose Smith has been brutally murdered. When the person who discovers Smith's body says, "Smith's murderer is insane", we may understand this as the attributive use of the definite description "Smith's murderer", and analyze the sentence according to Russell. This is because the discoverer might equivalently have worded the assertion, "Whoever killed Smith is insane." Now consider another speaker: suppose Jones, though innocent, has been arrested for the murder of Smith, and is now on trial. When a reporter sees Jones talking to himself outside the courtroom, and describes what she sees by saying, "Smith's murderer is insane", we may understand this as the referring use of the definite description, for we may equivalently reword the reporter's assertion thus: "That person who I see talking to himself, and who I believe murdered Smith, is insane." In this case, we should not accept Russell's analysis as correctly representing the reporter's assertion. On Russell's analysis, the sentence is to be understood as the conjunction of
If this analysis of the reporter's assertion were correct, then since Jones is innocent, we should take her to mean what the discoverer of Smith's body meant, that whoever murdered Smith is insane. We should then take her observation of Jones talking to himself to be irrelevant to the truth of her assertion. This clearly misses her point.
Thus the same sentence, "Smith's murderer is insane", can be used to mean quite different things in different contexts. There are, accordingly, contexts in which "the current Emperor of Germany is not gray" is false because no one is the current Emperor of Germany, and contexts in which it is a sentence referring to a person whom the speaker takes to be the current Emperor of Germany, true or false according to the hair of the impostor.
In Reference and Existence, Saul Kripke
argues that while Donnellan is correct to point out two uses of the phrase, it does not follow that the phrase is ambiguous between two meanings. For example, when the reporter finds out that Jones, the person she has been calling Smith's murderer did not murder Smith, she will admit that her use of the name was incorrect. Kripke defends Russell's analysis of definite descriptions, and argues that Donnellan does not adequately distinguish meaning from use, or, speaker's meaning from sentence meaning.
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS was a British philosopher, logician, mathematician, historian, and social critic. At various points in his life he considered himself a liberal, a socialist, and a pacifist, but he also admitted that he had never been any of these things...
's most significant contribution to the philosophy of language
Philosophy of language
Philosophy of language is the reasoned inquiry into the nature, origins, and usage of language. As a topic, the philosophy of language for analytic philosophers is concerned with four central problems: the nature of meaning, language use, language cognition, and the relationship between language...
. It is also known as Russell's Theory of Descriptions (commonly abbreviated as RTD). In short, Russell argued that the syntactic form of descriptions (phrases that took the form of "The aardvark" and "An aardvark") is misleading, as it does not correlate their logical and/or semantic architecture. While descriptions may seem fairly uncontroversial phrases, Russell argued that providing a satisfactory analysis of the linguistic and logical properties of a description is vital to clarity in important philosophical debates, particularly in semantic arguments, epistemology and metaphysics. It has been argued, for example, that RTD largely underpinned Russell's theory of sense-data.
Since the first development of the theory in Russell's 1905 paper "On Denoting
On Denoting
"On Denoting", written by Bertrand Russell, is one of the most significant and influential philosophical essays of the 20th century. It was published in the philosophy journal Mind in 1905; then reprinted, in both a special 2005 anniversary issue of the same journal and in Russell's Logic and...
", RTD has been hugely influential and well-received within the philosophy of language. However, it has not been without its critics. In particular, the philosophers P. F. Strawson
P. F. Strawson
Sir Peter Frederick Strawson FBA was an English philosopher. He was the Waynflete Professor of Metaphysical Philosophy at the University of Oxford from 1968 to 1987. Before that he was appointed as a college lecturer at University College, Oxford in 1947 and became a tutorial fellow the...
and Keith Donnellan
Keith Donnellan
Keith Donnellan is a contemporary philosopher and Professor Emeritus of the UCLA department of Philosophy. He has made important contributions to the philosophy of language, most notably to the analysis of proper names and definite descriptions...
have given notable, well known criticisms of the theory. Most recently, RTD has been defended by various philosophers and even developed in promising ways to bring it into harmony with generative grammar
Generative grammar
In theoretical linguistics, generative grammar refers to a particular approach to the study of syntax. A generative grammar of a language attempts to give a set of rules that will correctly predict which combinations of words will form grammatical sentences...
in Noam Chomsky
Noam Chomsky
Avram Noam Chomsky is an American linguist, philosopher, cognitive scientist, and activist. He is an Institute Professor and Professor in the Department of Linguistics & Philosophy at MIT, where he has worked for over 50 years. Chomsky has been described as the "father of modern linguistics" and...
's sense, particularly by Stephen Neale
Stephen Neale
Stephen Roy Albert Neale is Distinguished Professor of Philosophy and Linguistics and holder of the John H. Kornblith Family Chair in the Philosophy of Science and Values at the Graduate Center, City University of New York...
. Such developments have themselves been criticized, and debate continues.
Introduction
Bertrand Russell's theory of descriptions was initially put forth in his 1905 essay "On Denoting", published in the journal of philosophy Mind. Russell's theory is focused on the logical form of expressions involving denoting phrases, which he divides into three groups:- Denoting phrases which do not denote anything, for example "the current Emperor of Germany".
- Phrases which denote one definite object, for example "the present President of the U.S.A." We need not know which object the phrase refers to for it to be unambiguous, for example "the cutest kitten" is a unique individual but his or her actual identity is unknown.
- Phrases which denote ambiguously, for example, "an Aardvark".
Indefinite descriptions comprise Russell's third group. Descriptions most frequently appear in the standard subject-predicate form.
Russell put forward his theory of descriptions in order to solve a number of problems in the philosophy of language. The two major problems are (1) co-referring expressions and (2) non-referring expressions. The problem of co-referring expressions originated primarily with Gottlob Frege
Gottlob Frege
Friedrich Ludwig Gottlob Frege was a German mathematician, logician and philosopher. He is considered to be one of the founders of modern logic, and made major contributions to the foundations of mathematics. He is generally considered to be the father of analytic philosophy, for his writings on...
as the problem of informative identities. For example, if the morning star and the evening star are the same planet in the sky (indeed they are), how is it that someone can think that the morning star rises in the morning but the evening star does not? . This is apparently problematic because although the two expressions seem to denote the same thing, one cannot substitute one for the other, which one ought to be able to do with identical or synonymous expressions. This is even further complicated as both the Morning Star and Evening Star are also the planet Venus
Venus
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...
.
The problem of non-referring expressions is that certain expressions that are meaningful do not truly refer to anything. For example, by "any dog is annoying" it is not meant that there is a particular individual dog, namely any dog, that has the property of being annoying(similar considerations go for "some dog", "every dog", "a dog", and so on). Likewise, by "the current Emperor of Germany is gray" it is not meant that there is some individual, namely the current Emperor of Germany , who has the property of being gray; Germany is no longer a monarchy, so there is currently no Emperor. Thus, what Russell wants to avoid is admitting mysterious non-existent entities into his ontology
Ontology
Ontology is the philosophical study of the nature of being, existence or reality as such, as well as the basic categories of being and their relations...
. Furthermore, the law of the excluded middle requires that one of the following propositions, for example, must be true: either "the current Emperor of Germany is gray" or "it is not the case that the current Emperor of Germany is gray". Normally, propositions of the subject-predicate form are said to be true if and only if the subject is in the [extension] of the predicate. But, there is currently no Emperor of Germany. So, since the subject does not exist, it is not in the extension of either predicate (it is not on the list of gray people or non-gray people). Thus, it appears that this is a case in which the law of excluded middle is violated, which is also an indication that something has gone wrong.
Definite descriptions
Russell analyzes definite descriptions similarly to indefinite descriptions, except that the individual is now uniquely specified. Take as an example of a definite description the sentence "the current Emperor of Germany is gray". Russell analyzes this phrase into the following component parts (with 'x' and 'y' representing variables):- there is an x such that x is an emperor of Germany.
- for every x and every y, if both x and y are emperors of Germany, then y is x (i.e. there is at most one emperor of Germany).
- anything that is an emperor of Germany is gray.
Thus, a definite description (of the general form 'the F is G') becomes the following existentially quantified phrase in classic symbolic logic (where 'x' and 'y' are variables and 'F' and 'G' are predicates - in the example above, F would be "is an emperor of Germany", and G would be "is gray"):
- ∃x[(Fx & ∀y(Fy → x=y)) & Gx]
Informally, this reads as follows: something exists with the property F, there is only one such thing, and this unique thing also has the property G.
This analysis, according to Russell, solves the two problems noted above as related to definite descriptions:
- "The morning star rises in the morning" no longer needs to be thought of as having the subject-predicate form. It is instead analyzed as "there is one unique thing such that it is the morning star and it rises in the morning". Thus, strictly speaking, the two expressions "the morning star..." and "the evening star..." are not synonymous, so it makes sense that they cannot be substituted (the analyzed description of the evening star is "there is one unique thing such that it is the evening star and it rises in the evening"). This solves Gottlob FregeGottlob FregeFriedrich Ludwig Gottlob Frege was a German mathematician, logician and philosopher. He is considered to be one of the founders of modern logic, and made major contributions to the foundations of mathematics. He is generally considered to be the father of analytic philosophy, for his writings on...
's problem of informative identities. - Since the phrase "the current Emperor of Germany is gray" is not a referring expression, according to Russell's theory it need not refer to a mysterious non-existent entity. Russell says that if there are no entities X with property F, the proposition "X has property G" is false for all values of X.
Russell says that all propositions in which the Emperor of Germany has a primary occurrence are false. The denials of such propositions are true, but in these cases the Emperor of Germany has a secondary occurrence (the truth value of the proposition is not a function of the truth of the existence of the Emperor of Germany).
Indefinite descriptions
Take as an example of an indefinite description the sentence "some dog is annoying". Russell analyzes this phrase into the following component parts (with 'x' and 'y' representing variables):- there is an x such that x is a dog.
- x is being annoying.
Thus, an indefinite description (of the general form 'an D is A') becomes the following existentially quantified phrase in classic symbolic logic (where 'x' and 'y' are variables and 'D' and 'A' are predicates):
- ∃x[Dx & Ax]
Informally, this reads as follows: there is something such that it is D and A.
This analysis, according to Russell, solves the second problem noted above as related to indefinite descriptions. Since the phrase "some dog is annoying" is not a referring expression, according to Russell's theory, it need not refer to a mysterious non-existent entity. Furthermore, the law of excluded middle need not be violated (i.e. it remains a law), because "some dog is annoying" comes out true: there is a thing that is both a dog and annoying. Thus, Russell's theory seems to be a better analysis insofar as it solves several problems.
P. F. Strawson
P. F. StrawsonP. F. Strawson
Sir Peter Frederick Strawson FBA was an English philosopher. He was the Waynflete Professor of Metaphysical Philosophy at the University of Oxford from 1968 to 1987. Before that he was appointed as a college lecturer at University College, Oxford in 1947 and became a tutorial fellow the...
argued that Russell had failed to correctly represent what one means when one says a sentence in the form of "the current Emperor of Germany is gray." According to Strawson, this sentence is not contradicted by "No one is the current Emperor of Germany", for the former sentence contains not an existential assertion, but attempts to use "the current Emperor of Germany" as a referring (or denoting) phrase. Since there is no current Emperor of Germany, the phrase fails to refer to anything, and so the sentence is neither true nor false.
Keith Donnellan
According to Keith DonnellanKeith Donnellan
Keith Donnellan is a contemporary philosopher and Professor Emeritus of the UCLA department of Philosophy. He has made important contributions to the philosophy of language, most notably to the analysis of proper names and definite descriptions...
, there are two distinct ways we may use a definite description such as "the current Emperor of Germany is gray", and thus makes his distinction between the referential and the attributive use of a definite description. He argues that both Russell and Strawson make the mistake of attempting to analyze sentences removed from their context. We can mean different and distinct things while using the same sentence in different situations.
For example, suppose Smith has been brutally murdered. When the person who discovers Smith's body says, "Smith's murderer is insane", we may understand this as the attributive use of the definite description "Smith's murderer", and analyze the sentence according to Russell. This is because the discoverer might equivalently have worded the assertion, "Whoever killed Smith is insane." Now consider another speaker: suppose Jones, though innocent, has been arrested for the murder of Smith, and is now on trial. When a reporter sees Jones talking to himself outside the courtroom, and describes what she sees by saying, "Smith's murderer is insane", we may understand this as the referring use of the definite description, for we may equivalently reword the reporter's assertion thus: "That person who I see talking to himself, and who I believe murdered Smith, is insane." In this case, we should not accept Russell's analysis as correctly representing the reporter's assertion. On Russell's analysis, the sentence is to be understood as the conjunction of
- there is an x such that x murdered Smith;
- there is no y, y not equal x, such that y murdered Smith; and
- x is insane.
If this analysis of the reporter's assertion were correct, then since Jones is innocent, we should take her to mean what the discoverer of Smith's body meant, that whoever murdered Smith is insane. We should then take her observation of Jones talking to himself to be irrelevant to the truth of her assertion. This clearly misses her point.
Thus the same sentence, "Smith's murderer is insane", can be used to mean quite different things in different contexts. There are, accordingly, contexts in which "the current Emperor of Germany is not gray" is false because no one is the current Emperor of Germany, and contexts in which it is a sentence referring to a person whom the speaker takes to be the current Emperor of Germany, true or false according to the hair of the impostor.
In Reference and Existence, Saul Kripke
Saul Kripke
Saul Aaron Kripke is an American philosopher and logician. He is a professor emeritus at Princeton and teaches as a Distinguished Professor of Philosophy at the CUNY Graduate Center...
argues that while Donnellan is correct to point out two uses of the phrase, it does not follow that the phrase is ambiguous between two meanings. For example, when the reporter finds out that Jones, the person she has been calling Smith's murderer did not murder Smith, she will admit that her use of the name was incorrect. Kripke defends Russell's analysis of definite descriptions, and argues that Donnellan does not adequately distinguish meaning from use, or, speaker's meaning from sentence meaning.
External links
- Russell's Theory of Descriptions - section 2 of Ludlow's article on the Stanford Encyclopedia of Philosophy.
- Russell's Theory of Descriptions - by Thomas C Ryckman.
- Russell's theory of descriptions - at Oxford University's Introduction to Logic.
- Russell's Theory of Descriptions special issue of Mind celebrating the 100th anniversary of Russell's "On Denoting" in which the theory of descriptions was first presented.