An ontological commitment of a language is one or more objects postulated to exist by that language. The 'existence' referred to need not be 'real', but exist only in a
universe of discourse
In the formal sciences, the domain of discourse, also called the universe of discourse, universal set, or simply universe, is the set of entities over which certain variables of interest in some formal treatment may range.
Overview
The domain ...
. As an example, legal systems use vocabulary referring to 'legal persons' that are collective entities that have rights. One says the legal doctrine has an ''ontological commitment'' to non-singular individuals.
[
In ]information system
An information system (IS) is a formal, sociotechnical, organizational system designed to collect, process, store, and distribute information. From a sociotechnical perspective, information systems are composed by four components: task, people ...
s and artificial intelligence
Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech re ...
, where an ontology
In metaphysics, ontology is the philosophical study of being, as well as related concepts such as existence, becoming, and reality.
Ontology addresses questions like how entities are grouped into categories and which of these entities exis ...
refers to a specific vocabulary and a set of explicit assumptions about the meaning and usage of these words, an ontological commitment is an agreement to use the shared vocabulary in a coherent and consistent manner within a specific context.[
In ]philosophy
Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...
, a "theory is ontologically committed to an object only if that object occurs in ''all'' the ontologies of that theory."[
]
Background
The sentence “Napoleon is one of my ancestors” apparently commits us only to the existence of two individuals (i.e., Napoleon
Napoleon Bonaparte ; it, Napoleone Bonaparte, ; co, Napulione Buonaparte. (born Napoleone Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French military commander and political leader who ...
and the speaker) and a line of ancestry between them. The fact that no other people or objects are mentioned seems to limit the “commitment” of the sentence. However, it is well known that sentences of this kind cannot be interpreted in first-order logic
First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantifie ...
, where individual variables stand for individual things. Instead, they must be represented in some second-order
Second-order may refer to:
Mathematics
* Second order approximation, an approximation that includes quadratic terms
* Second-order arithmetic, an axiomatization allowing quantification of sets of numbers
* Second-order differential equation, a di ...
form. In ordinary language, such second-order forms use either grammatical plurals or terms such as “set of” or “group of”.
For example, the sentence involving Napoleon can be rewritten as “any group of people that includes me and the parents of each person in the group must also include Napoleon,” which is easily interpreted as a statement in second-order logic (one would naturally start by assigning a name, such as ''G'', to the group of people under consideration). Formally, collective noun forms such as “a group of people” are represented by second-order variables, or by first-order variables standing for sets (which are well-defined
In mathematics, a well-defined expression or unambiguous expression is an expression whose definition assigns it a unique interpretation or value. Otherwise, the expression is said to be ''not well defined'', ill defined or ''ambiguous''. A funct ...
objects in mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
and logic). Since these variables do not stand for individual objects, it seems we are “ontologically committed” to entities other than individuals — sets, classes, and so on. As Quine puts it,
the general adoption of class variables of quantification ushers in a theory whose laws were not in general expressible in the antecedent levels of logic. The price paid for this increased power is ontological
In metaphysics, ontology is the philosophical study of being, as well as related concepts such as existence, becoming, and reality.
Ontology addresses questions like how entities are grouped into categories and which of these entities exis ...
: objects of a special and abstract kind, viz.
The abbreviation ''viz.'' (or ''viz'' without a full stop) is short for the Latin , which itself is a contraction of the Latin phrase ''videre licet'', meaning "it is permitted to see". It is used as a synonym for "namely", "that is to say", "to ...
classes, are now presupposed. Formally it is precisely in allowing quantification over class variables α, β, etc., that we assume a range of values for these variables to refer to. To be assumed as an entity is to be assumed as a value of a variable. (''Methods of Logic'', 1950, p. 228)
Another statement about individuals that appears “ontologically innocent” is the well-known Geach–Kaplan sentence In formal logic, nonfirstorderizability is the inability of a natural-language statement to be adequately captured by a formula of first-order logic. Specifically, a statement is nonfirstorderizable if there is no formula of first-order logic which ...
: ''Some critics admire only one another.''
Quine's criterion
Willard Van Orman Quine
Willard Van Orman Quine (; known to his friends as "Van"; June 25, 1908 – December 25, 2000) was an American philosopher and logician in the analytic tradition, recognized as "one of the most influential philosophers of the twentieth century". ...
provided an early and influential formulation of ontological commitment:[
The purpose of Quine's strategy is to determine just how the ''ontological commitment'' of a theory is to be found. Quine argued that the only ontologically committing expressions are variables bound by a first-order existential quantifier, and natural language expressions which were formalized using variables bound by first-order existential quantifiers.][
Attempts have been made to argue that ]predicate
Predicate or predication may refer to:
* Predicate (grammar), in linguistics
* Predication (philosophy)
* several closely related uses in mathematics and formal logic:
**Predicate (mathematical logic)
**Propositional function
**Finitary relation, o ...
s are also ontologically committing, and thus that subject-predicate sentences bear additional ontological commitment to abstract object
In metaphysics, the distinction between abstract and concrete refers to a divide between two types of entities. Many philosophers hold that this difference has fundamental metaphysical significance. Examples of concrete objects include plants, hum ...
s such as universal
Universal is the adjective for universe.
Universal may also refer to:
Companies
* NBCUniversal, a media and entertainment company
** Universal Animation Studios, an American Animation studio, and a subsidiary of NBCUniversal
** Universal TV, a ...
s, sets, or classes. It has been suggested that the use of meaningful names in nonexistence statements such as "Pegasus does not exist" brings with it an ontological commitment to empty name In metaphysics and the philosophy of language, an empty name is a proper name that has no referent.
The problem of empty names is the idea that empty names have a meaning when it seems they should not have. The name " Pegasus" is empty; there is ...
s like Pegasus, a quandary referred to as Plato's beard
In metaphysics, Plato's beard is a paradoxical argument dubbed by Willard Van Orman Quine in his 1948 paper "On What There Is". The phrase came to be identified as the philosophy of understanding something based on what does not exist.
Doctrine ...
and escaped by using quantifiers.[
This discussion has a connection to the Carnap–Quine argument over analytic and synthetic objects.][ Although Quine refers to 'ontological commitment' in this connection,][ in his rejection of the analytic/synthetic distinction he does not rely upon the formal translation of any particular theory along the lines he has suggested.][ Instead, Quine argues by using examples that although there are tautological statements in a formal theory, like "all squares are rectangles", a formal theory necessarily contains references to objects that are not tautological, but have external connections. That is, there is an ''ontological commitment'' to such external objects. In addition, the terms used to interpret the application of the theory are not simply descriptions of sensory input, but are statements in a context. That is, inversely, there is an ''ontological commitment'' of these observational objects to the formal theory. As Ryan puts it: "Rather than being divided between contingent synthetic claims and indubitable analytic propositions, our beliefs constitute a continuous range from a periphery of sense-reports to interior concepts that are comparatively theory-laden and general."][ Thus we end up with Quine's 'flat' ontology that does not see a distinction between analytic and synthetic objects.][
Quine further made a distinction between the ontological commitments of a theory (what the theory says exists) and the ideological commitments of a theory (those concepts, logical or non-logical, that are expressible within the theory)."Ontological Commitment"]
''Stanford Encyclopedia of Philosophy
The ''Stanford Encyclopedia of Philosophy'' (''SEP'') combines an online encyclopedia of philosophy with peer-reviewed publication of original papers in philosophy, freely accessible to Internet users. It is maintained by Stanford University. Eac ...
''.
Ontological parsimony
Whatever process one uses to determine the ontological commitments of a theory, that does not prescribe what ontological commitments one should have. Quine regarded this as a matter of epistemology
Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics.
Episte ...
, which theory one should accept. "Appeal is made to oncerns ofexplanatory power, parsimony, conservatism, precision, and so on".[
Ontological parsimony can be defined in various ways, and often is equated to versions of ]Occam's razor
Occam's razor, Ockham's razor, or Ocham's razor ( la, novacula Occami), also known as the principle of parsimony or the law of parsimony ( la, lex parsimoniae), is the problem-solving principle that "entities should not be multiplied beyond neces ...
, a "rule of thumb, which obliges us to favor theories or hypotheses that make the fewest unwarranted, or ''ad hoc'', assumptions about the data from which they are derived."[ Glock regards 'ontological parsimony' as one of the 'five main points' of Quine's conception of ontology.][
Following Quine,][ Baker states that a theory, ''T'', is ''ontologically committed'' to items ''F'' if and only if ''T'' entails that ''F′''s exist. If two theories, ''T1'' and ''T2'', have the same ontological commitments except that ''T2'' is ontologically committed to ''F′''s while ''T1'' is not, then ''T1'' is more parsimonious than ''T2''. More generally, a sufficient condition for ''T1'' being more parsimonious than ''T2'' is for the ontological commitments of ''T1'' to be a proper subset of those of ''T2''.][
These ideas lead to the following particular formulation of Occam's razor: 'Other things being equal, if ''T1'' is more ontologically parsimonious than ''T2'' then it is rational to prefer ''T1'' to ''T2''.' While a common formulation stipulates only that entities should not be multiplied beyond necessity, this version by contrast, states that entities should not be multiplied ''other things being equal'', and this is compatible with parsimony being a comparatively weak theoretical virtue.][
]
Recent controversies
The standard approach to ontological commitment has been that, once a theory has been regimented and/or "paraphrased" into an agreed "canonical" version,[ which may indeed be in formal logical notation rather than the original language of the theory, ontological commitments can be read off straightforwardly from the presence of certain ontologically committing expressions (e.g. bound variables of existential quantification). Although there is substantial debate about which expressions are ontologically committing,][ parties to that debate generally agree that the expressions they prefer are reliable bearers of ontological commitment, imparting ontological commitment to all regimented sentences in which they occur. This assumption has been challenged.
Inwagen has taken issue with Quine's methodology,][ claiming that this process did not lead to a unique set of fundamental objects, but to several possible sets, and one never could be certain that all the possible sets had been found. He also took issue with Quine's notion of a theory, which he felt was tantamount to suggesting a 'theory' was just a collection of sentences. Inwagen suggested that Quine's approach provided useful tools for discovering what entities were ontological commitments, but that he had not been successful. His attempts are comparable to an "attempt to reach the moon by climbing ever higher trees..."][
It has been suggested that the ontological commitments of a theory cannot be discerned by analysis of the syntax of sentences, looking for ontologically committing expressions, because the true ontological commitments of a sentence (or theory) are restricted to the entities needed to serve as ]truthmaker
Truthmaker theory is "the branch of metaphysics that explores the relationships between what is true and what exists". The basic intuition behind truthmaker theory is that truth depends on being. For example, a perceptual experience of a green tre ...
s for that sentence, and the syntax of even a regimented or formalized sentence is not a reliable guide to what entities are needed to make it true.[ However, this view has been attacked by Jonathan Schaffer, who has argued that truthmaking is not an adequate test for ontological commitment: at best, the search for the truthmakers of our theory will tell us what is "fundamental", but not what our theory is ontologically committed to, and hence will not serve as a good way of deciding what exists.][
It also has been argued that the syntax of sentences is not a reliable guide to their ontological commitments because English has no form of words which reliably functions to make an existence-claim in every context in which it is used. For example, Jody Azzouni suggests that "There is" does not make any kind of genuine existence-claim when it is used in a sentence such as "There are mice that talk". Since the meaning of the existential quantifier in formal notation is usually explained in terms of its equivalence to English expressions such as "there is" and "there exist", and since these English expressions are not reliably ontologically committing, it comes to seem that we cannot be sure of our theory's ontological commitments even after it has been regimented into a canonical formulation.][ This argument has been attacked by Howard Peacock,][ who suggests that Azzouni's strategy conflates two different kinds of ontological commitment – one which is intended as a measure of what a theory explicitly claims to exist, and one which is intended as a measure of what is required for the theory to be true; what the ontological costs of the theory are. If ontological commitment is thought of as a matter of the ontological costs of a theory, then it is possible that a sentence may be ontologically committed to an entity even though competent speakers of the language do not recognize the sentence as asserting the existence of that entity. Ontological commitment is not a matter of what commitments one explicitly recognizes, but rather a matter of what commitments are actually incurred.
]
See also
*Conceptualization (information science)
In information science a conceptualization is an abstract simplified view of some selected part of the world, containing the objects, concepts, and other entities that are presumed of interest for some particular purpose and the relationships betw ...
*Holophrastic indeterminacy
Holophrastic indeterminacy, or indeterminacy of sentence translation, is one of two kinds of indeterminacy of translation to appear in the writings of philosopher W. V. O. Quine. According to Quine, "there is more than one correct method of transla ...
*Indeterminacy of translation The indeterminacy of translation is a thesis propounded by 20th-century American analytic philosopher W. V. Quine. The classic statement of this thesis can be found in his 1960 book ''Word and Object'', which gathered together and refined much of Qu ...
References
External links
*{{cite SEP , url-id=ontological-commitment , title=Ontological Commitment , last=Bricker , first=Phillip
Ontological commitment
a category in Philosophical Papers maintained by Henry Laycock
Ontology
Philosophy of language
Logic