Theory of descriptions

The theory of descriptions is one of the philosopher Bertrand Russell's most significant contributions to the philosophy of language. It is also termed Russell's Theory of Descriptions (often abbreviated as "RTD"). In short, Russell argued that the superficial syntactic form of descriptions (phrases usually of the form "The X" and "An X") is misleading, as it does not match their logical or semantic structure. While descriptions may seem fairly insignificant phrases, Russell and others have argued that providing a satisfactory analysis of their linguistic and logical properties is vital to clarity in important philosophical debates, particularly in semantics, epistemology and metaphysics. It has been argued, for example, that RTD largely underpinned Russell's theory of sense-data.

Since the initial development of the view in Russell's 1905 paper "On Denoting", RTD has been highly influential and well-received among many philosophers. However, it has not been without criticism. In particular, the philosophers P. F. Strawson and Keith Donnellan have given notable criticisms of the theory. More recently, RTD has been defended and developed in promising ways to harmonize with generative grammar in Noam Chomsky's sense, particularly by Stephen Neale. Such developments have themselves been criticized, and debate continues.

Introduction

Russell's theory of descriptions was most clearly expressed in his 1905 essay "On Denoting", published in the philosophy journal "Mind". Russell's theory is about the logical form of expressions involving denoting phrases, which he divides into three groups:

# Denoting phrases which do not denote anything, for example "the present King of France".
# Phrases which denote one definite object, for example "the present King of England" (Edward VII at the time Russell was writing). We need not know which object the phrase refers to for it to be unambiguous, for example "the tallest spy" is a unique individual but his or her actual identity is unknown).
# Phrases which denote ambiguously, for example, "a man".

"Definite descriptions" involve Russell's second group of denoting phrases, and "indefinite descriptions" involve Russell's third group. Descriptions typically appear to be of the standard subject-predicate form. Russell proposed his theory of descriptions in order to solve several problems in the philosophy of language. The two major problems are of (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? That is, someone might find it surprising that the two names refer to the same thing (i.e. the identity is informative). 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 identitical or synonymous expressions.

The problem of non-referring expressions is that certain expressions that are meaningful do not seem to refer to anything. For example, by "any man is sexist" it is not meant that there is a particular individual, namely "any man", that has the property of being sexist (similar considerations go for "some man", "every man", "a man", and so on). Likewise, by "the present King of France is bald" it is not meant that there is some individual, namely "the present King of France", who has the property of being bald (France is no longer a monarchy, so there is currently no King of France). 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 present King of France is bald" or "it is not the case that the present King of France is bald". 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 King of France. So, since the subject does not exist, it is not in the extension of either predicate (it is not on the list of bald people or non-bald 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. Russell says in his paper, in a typically sly dig at a school of philosophy with which he disagreed, that "Hegelians, who love a synthesis, will probably conclude that he wears a wig."

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 present King of France is bald". Russell analyzes this phrase into the following component parts (with 'x' and 'y' representing variables):

#there is an x such that x is the King of France.
#there is no y, other than x, such that y is the King of France (i.e., x is uniquely the King of France).
#x is bald.

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 the King of France", and G would be "is bald"):

:∃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 analysed description of the evening star is "there is one unique thing such that it is the evening star and it rises in the evening").
# Since the phrase "the present King of France is bald" 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 C with property F, the proposition "C has property G" is false for "all" values of G.

Russell writes:

Russell says that all propositions in which the King of France has a primary occurrence are false. The denials of such propositions are true, but in these cases the King of France has a secondary occurrence (the truth value of the proposition is not a function of the truth of the existence of the King of France).

Indefinite descriptions

Take as an example of an indefinite description the sentence "some man is being obnoxious". Russell analyzes this phrase into the following component parts (with 'x' and 'y' representing variables):

#there is an x such that x is a man.
#x is being obnoxious.

Thus, an indefinite description (of the general form 'an 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):

:∃x [Fx & Gx]

Informally, this reads as follows: there is something such that it is F and G.

This analysis, according to Russell, solves the second problem noted above as related to indefinite descriptions. Since the phrase "some man is being obnoxious" 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 man is being obnoxious" comes out true: there is a person that is both a man and obnoxious. Thus, Russell's theory seems to be a better analysis insofar as it solves several problems.

Criticism of Russell's analysis

P. F. Strawson

P. F. Strawson argued that Russell had misrepresented what one means when one says "The present King of France is bald." According to Strawson, this sentence is not contradicted by "No one is the present King of France," for the former sentence contains not an existential assertion, but attempts to "use" "the present King of France" as a referring (or denoting) phrase. Since there is no present King of France, the phrase fails to refer, and so the sentence is neither true nor false.

Keith Donnellan

According to Keith Donnellan, there are two distinct ways we may use a definite description such as "the present King of France," and thus makes his distinction (to be illustrated below) between the "referring" (referential) and the "nonreferring" (attributive) use of a definite description. He argues that Russell and Strawson both make the mistake of attempting to analyse sentences removed from context. We can mean different things by the same sentence used 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 nonreferring use of the definite description "Smith's murderer," and analyse 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 present King of France is not bald" is false because no one is the present King of France, and contexts in which it is a sentence referring to a person whom the speaker takes to be the present King of France, true or false according to the scalp of this impostor.

In "Reference and Existence", [Kripke's unpublished John Locke lectures at Oxford in 1973] 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.

Notes

References and further reading

* Bertolet, Rod. (1999). "Theory of Descriptions", "The Cambridge Dictionary of Philosophy", second edition. New York: Cambridge University Press.
* Donnellan, Keith. (1966). "Reference and Definite Descriptions", "Philosophical Review", 75, pp. 281-304.
* Kripke, Saul. (1977). "Speaker's Reference and Semantic Reference", "Midwest Studies in Philosophy", 2, pp. 255–276.
* Ludlow, Peter. (2005). "Descriptions", "The Stanford Encyclopedia of Philosophy", E. Zalta (ed.). [http://plato.stanford.edu/archives/sum2005/entries/descriptions/ Online text]
* Neale, Stephen. (1990) Descriptions Bradford, MIT Press.
* Neale, Stephen. (2005) "A Century Later", Mind 114, pp. 809–871.
* Ostertag, Gary (ed.). (1998) Definite Descriptions: A Reader Bradford, MIT Press. (Includes Donnellan (1966), Kripke (1977), Chapter 3 of Neale (1990), Russell (1905), Chapter 16 of Russell (1919). and Strawson (1950).)
* Russell, Bertrand. (1905). "On Denoting", Mind 14, pp. 479-493. [http://www.fh-augsburg.de/~harsch/anglica/Chronology/20thC/Russell/rus_deno.html Online text]
* Russell, Bertrand. (1919). "Introduction to Mathematical Philosophy", London: George Allen and Unwin.
* Strawson, P. F. (1950). "On Referring", Mind 59, pp. 320-344.

ee also

* Bertrand Russell
* Definite description
* Sense and reference
* Philosophy of language

External links

* [http://plato.stanford.edu/entries/descriptions/#2 Russell's Theory of Descriptions] - section 2 of Ludlow's article on the "Stanford Encyclopedia of Philosophy".
* [http://www.lawrence.edu/fac/ryckmant/Russell%27s%20Theory%20of%20Descriptions.htm Russell's Theory of Descriptions] - by Thomas C Ryckman.
* [http://logic.philosophy.ox.ac.uk/tutorial6/Tut6-03.htm Russell's theory of descriptions] - at Oxford University's Introduction to Logic.
* [http://mind.oxfordjournals.org/content/vol114/issue456/index.dtl 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.