Rigid designator
Encyclopedia
In modal logic
and the philosophy of language
, a term is said to be a rigid designator (or Kripkean soul) when it designates (picks out, denotes, refers to) the same thing in all possible worlds
in which that thing exists and does not designate anything else in those possible worlds in which that thing does not exist. A designator is persistently rigid if it designates the same thing in every possible world in which that thing exists and designates nothing in all other possible worlds. A designator is obstinately rigid if it designates the same thing in every possible world, period, whether or not that thing exists in that world. Rigid designators are contrasted with non-rigid or flaccid designator
s, which may designate different things in different possible worlds.
in the lectures that became Naming and Necessity
, in the course of his argument against descriptivist
theories of reference, building on the work of Ruth Barcan Marcus
. At the time of Kripke's lectures, the dominant theories of reference in Analytic philosophy
(associated with the theories of Gottlob Frege
and Bertrand Russell
) held that the meaning of sentences involving proper names could be given by substituting a contextually appropriate description for the name. Russell, for example, famously held that someone who had never met Otto von Bismarck
might know of him as the first Chancellor of the German Empire, and if so, his statement that (say) "Bismarck was a ruthless politician" should be understood to mean "The first Chancellor of the German Empire was a ruthless politician" (which could in turn be analysed into a series of more basic statements according to the method Russell introduced in his theory of definite descriptions). Kripke argued — against both the Russellian analysis and several attempted refinements of it — that such descriptions could not possibly mean the same thing as the name "Bismarck," on the grounds that proper names such as "Bismarck" always designate rigidly, whereas descriptions such as "the first Chancellor of the German Empire" do not. Thus, for example, it might have been the case that Bismarck died in infancy. If so, he would not have ever satisfied the description "the first Chancellor of the German Empire," and (indeed) someone else probably would have. It does not follow that the first Chancellor of the German Empire may not have been the first Chancellor of the German Empire—that is (at least according to its surface-structure) a contradiction. Kripke argues that the way that proper names work is that when we make statements about what might or might not have been true of Bismarck, we are talking about what might or might not have been true of that particular person in various situations, whereas when we make statements about what might or might not have been true of, say, the first Chancellor of the German Empire we could be talking about what might or might not have been true of whoever would have happened to fill that office in those situations.
The "could" here is important to note: rigid designation is a property of the way terms are used, not a property of the terms themselves, and some philosophers, following Keith Donnellan
, have argued that a phrase such as "the first Chancellor of the German Empire" could be used rigidly, in sentences such as "the first Chancellor of the German Empire could have decided never to go into politics." Kripke himself doubted that there was any need to recognize rigid uses of definite descriptions, and argued that Russell
's notion of scope offered all that was needed to account for such sentences. But in either case, Kripke argued, nothing important in his account depends on the question (see: Naming and Necessity p. 6n8, p. 59n22). Whether definite descriptions can be used rigidly or not, they can at least sometimes be used non-rigidly, but a proper name can only be used rigidly; the asymmetry, Kripke argues, demonstrates that no definite description could give the meaning of a proper name—although it might be used to explain who a name refers to (that is, to "fix the referent" of the name).
, Kripke argues that proper name
s and certain natural kind
terms—including biological taxa
and types of natural substances (most famously, "water" and "H2O") designate rigidly. He argues for a form of scientific essentialism
not unlike Aristotelian essentialism. Essential properties are common to an object in all possible worlds, and so they pick out the same objects in all possible worlds - they rigidly designate.
' refers to one particular person in all possible worlds is because some person initially gave the name to him by saying something like "Let's call our baby 'Johnny Depp'". This is called the initial baptism. This usage of 'Johnny Depp' for referring to some particular baby got passed on from person-to-person in a giant causal and historical chain of events
. That is why everybody calls Johnny Depp 'Johnny Depp'. Johnny's mother passed it onto her friends who passed it onto their friends who passed it onto their friends, and so on.
is H2O, then water is necessarily H2O. Since the terms 'water' and 'H2O' pick out the same object in every possible world, there is no possible world in which 'water' picks out something different from 'H2O'. Therefore, water is necessarily H2O. It is possible, of course, that we are mistaken about the chemical composition of water, but that does not affect the necessity of identities. What is not being claimed is that water is necessarily H2O, but conditionally, if water is H2O (though we may not know this, it does not change the fact if it is true), then water is necessarily H2O.
Modal logic
Modal logic is a type of formal logic that extends classical propositional and predicate logic to include operators expressing modality. Modals — words that express modalities — qualify a statement. For example, the statement "John is happy" might be qualified by saying that John is...
and 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...
, a term is said to be a rigid designator (or Kripkean soul) when it designates (picks out, denotes, refers to) the same thing in all possible worlds
Possible Worlds
Possible Worlds may refer to:* Possible worlds, a concept in philosophy* Possible Worlds , by John Mighton** Possible Worlds , by Robert Lepage, based on the Mighton play* Possible Worlds , by Peter Porter...
in which that thing exists and does not designate anything else in those possible worlds in which that thing does not exist. A designator is persistently rigid if it designates the same thing in every possible world in which that thing exists and designates nothing in all other possible worlds. A designator is obstinately rigid if it designates the same thing in every possible world, period, whether or not that thing exists in that world. Rigid designators are contrasted with non-rigid or flaccid designator
Flaccid designator
In the philosophy of language and modal logic, a non-rigid designator is a term that does not extensionally refer to the same object in all possible worlds. For example, consider the phrase "The 43rd president of the United States of America": while the 43rd president of the United States is...
s, which may designate different things in different possible worlds.
Proper Names and Definite Descriptions
The notion of rigid designation was first introduced by Saul KripkeSaul 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...
in the lectures that became Naming and Necessity
Naming and Necessity
Naming and Necessity is a book by the philosopher Saul Kripke that was first published in 1980 and deals with the debates of proper nouns in the philosophy of language. The book is based on a transcript of three lectures given at Princeton University in 1970...
, in the course of his argument against descriptivist
Descriptivism
Descriptivism can refer to:*Descriptivist theory of names in philosophy*Descriptive linguistics...
theories of reference, building on the work of Ruth Barcan Marcus
Ruth Barcan Marcus
Ruth Barcan Marcus is the American philosopher and logician after whom the Barcan formula is named. She is a pioneering figure in the quantification of modal logic and the theory of direct reference...
. At the time of Kripke's lectures, the dominant theories of reference in Analytic philosophy
Analytic philosophy
Analytic philosophy is a generic term for a style of philosophy that came to dominate English-speaking countries in the 20th century...
(associated with the theories of 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...
and Bertrand Russell
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...
) held that the meaning of sentences involving proper names could be given by substituting a contextually appropriate description for the name. Russell, for example, famously held that someone who had never met Otto von Bismarck
Otto von Bismarck
Otto Eduard Leopold, Prince of Bismarck, Duke of Lauenburg , simply known as Otto von Bismarck, was a Prussian-German statesman whose actions unified Germany, made it a major player in world affairs, and created a balance of power that kept Europe at peace after 1871.As Minister President of...
might know of him as the first Chancellor of the German Empire, and if so, his statement that (say) "Bismarck was a ruthless politician" should be understood to mean "The first Chancellor of the German Empire was a ruthless politician" (which could in turn be analysed into a series of more basic statements according to the method Russell introduced in his theory of definite descriptions). Kripke argued — against both the Russellian analysis and several attempted refinements of it — that such descriptions could not possibly mean the same thing as the name "Bismarck," on the grounds that proper names such as "Bismarck" always designate rigidly, whereas descriptions such as "the first Chancellor of the German Empire" do not. Thus, for example, it might have been the case that Bismarck died in infancy. If so, he would not have ever satisfied the description "the first Chancellor of the German Empire," and (indeed) someone else probably would have. It does not follow that the first Chancellor of the German Empire may not have been the first Chancellor of the German Empire—that is (at least according to its surface-structure) a contradiction. Kripke argues that the way that proper names work is that when we make statements about what might or might not have been true of Bismarck, we are talking about what might or might not have been true of that particular person in various situations, whereas when we make statements about what might or might not have been true of, say, the first Chancellor of the German Empire we could be talking about what might or might not have been true of whoever would have happened to fill that office in those situations.
The "could" here is important to note: rigid designation is a property of the way terms are used, not a property of the terms themselves, and some philosophers, following 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 argued that a phrase such as "the first Chancellor of the German Empire" could be used rigidly, in sentences such as "the first Chancellor of the German Empire could have decided never to go into politics." Kripke himself doubted that there was any need to recognize rigid uses of definite descriptions, and argued that Russell
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 notion of scope offered all that was needed to account for such sentences. But in either case, Kripke argued, nothing important in his account depends on the question (see: Naming and Necessity p. 6n8, p. 59n22). Whether definite descriptions can be used rigidly or not, they can at least sometimes be used non-rigidly, but a proper name can only be used rigidly; the asymmetry, Kripke argues, demonstrates that no definite description could give the meaning of a proper name—although it might be used to explain who a name refers to (that is, to "fix the referent" of the name).
Essentialism
In Naming and NecessityNaming and Necessity
Naming and Necessity is a book by the philosopher Saul Kripke that was first published in 1980 and deals with the debates of proper nouns in the philosophy of language. The book is based on a transcript of three lectures given at Princeton University in 1970...
, Kripke argues that proper name
Proper name
"A proper name [is] a word that answers the purpose of showing what thing it is that we are talking about" writes John Stuart Mill in A System of Logic , "but not of telling anything about it"...
s and certain natural kind
Natural kind
In philosophy, a natural kind is a "natural" grouping, not an artificial one. Or, it is something that a set of things has in common which distinguishes it from other things as a real set rather than as a group of things arbitrarily lumped together by a person or group of people.If any natural...
terms—including biological taxa
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
and types of natural substances (most famously, "water" and "H2O") designate rigidly. He argues for a form of scientific essentialism
Scientific essentialism
Scientific essentialism, a view espoused by Saul Kripke and Hilary Putnam, maintains that there exist essential properties that objects possess necessarily. In other words, having such and such essential properties is a necessary condition for membership in a given natural kind...
not unlike Aristotelian essentialism. Essential properties are common to an object in all possible worlds, and so they pick out the same objects in all possible worlds - they rigidly designate.
Causal-Historical Theory of Reference
Proper names rigidly designate for reasons that differ from natural kinds terms. The reason 'Johnny DeppJohnny Depp
John Christopher "Johnny" Depp II is an American actor, producer and musician. He has won the Golden Globe Award and Screen Actors Guild award for Best Actor. Depp rose to prominence on the 1980s television series 21 Jump Street, becoming a teen idol...
' refers to one particular person in all possible worlds is because some person initially gave the name to him by saying something like "Let's call our baby 'Johnny Depp'". This is called the initial baptism. This usage of 'Johnny Depp' for referring to some particular baby got passed on from person-to-person in a giant causal and historical chain of events
Causal theory of reference
A causal theory of reference is a theory of how terms acquire specific referents. Such theories have been used to describe many referring terms, particularly logical terms, proper names, and natural kind terms...
. That is why everybody calls Johnny Depp 'Johnny Depp'. Johnny's mother passed it onto her friends who passed it onto their friends who passed it onto their friends, and so on.
Necessary Identities
One interesting consequence of Kripke semantics is that identities involving rigid designators are necessary. If waterWater
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
is H2O, then water is necessarily H2O. Since the terms 'water' and 'H2O' pick out the same object in every possible world, there is no possible world in which 'water' picks out something different from 'H2O'. Therefore, water is necessarily H2O. It is possible, of course, that we are mistaken about the chemical composition of water, but that does not affect the necessity of identities. What is not being claimed is that water is necessarily H2O, but conditionally, if water is H2O (though we may not know this, it does not change the fact if it is true), then water is necessarily H2O.
See also
- Naming and NecessityNaming and NecessityNaming and Necessity is a book by the philosopher Saul Kripke that was first published in 1980 and deals with the debates of proper nouns in the philosophy of language. The book is based on a transcript of three lectures given at Princeton University in 1970...
- Causal theory of referenceCausal theory of referenceA causal theory of reference is a theory of how terms acquire specific referents. Such theories have been used to describe many referring terms, particularly logical terms, proper names, and natural kind terms...
- classClass (philosophy)Philosophers sometimes distinguish classes from types and kinds. We can talk about the class of human beings, just as we can talk about the type , human being, or humanity...
versus instance - Counterpart theoryCounterpart theoryIn philosophy, specifically in the area of modal metaphysics, counterpart theory is an alternative to standard possible-worlds semantics for interpreting quantified modal logic. Counterpart theory still presupposes possible worlds, but differs in certain important respects from the Kripkean view...
- Flaccid designatorFlaccid designatorIn the philosophy of language and modal logic, a non-rigid designator is a term that does not extensionally refer to the same object in all possible worlds. For example, consider the phrase "The 43rd president of the United States of America": while the 43rd president of the United States is...
- Scientific essentialismScientific essentialismScientific essentialism, a view espoused by Saul Kripke and Hilary Putnam, maintains that there exist essential properties that objects possess necessarily. In other words, having such and such essential properties is a necessary condition for membership in a given natural kind...