## 1. Natural Language Ontology as an Emerging Discipline and Practice


### 1.1 Natural Language Ontology as a Discipline



The subject matter of natural language ontology is the ontology
implicit in natural language, which is to be distinguished from the
ontologies of the various metaphysical theories or naive
philosophical views formulated by using natural language. Natural
language ontology has as its task to uncover the ontology that is
reflected in relevant sorts of linguistic intuitions, setting aside
the question whether that ontology is real or merely apparent.



This entry uses "natural language ontology" as the term
for the discipline and "the ontology of natural language"
as a term for its subject matter. The more accurate term for the
subject matter of natural language ontology would actually be
"the ontologies of natural languages", since natural
languages may, in principle, reflect different ontologies and even the
same language (or idiolect) might reflect different ontologies. For
most of the entry, this is simplified by talking about *the*
ontology of natural language, addressing the issue of different
ontologies only in
 Section 4.
 This is justified by the fact that philosophers practicing natural
language ontology generally presuppose that there is a single ontology
shared by natural languages, as do, to a great extent at least,
semanticists.



Natural language ontology had been suggested as a discipline first by
Bach (1986), who uses the term "natural language
metaphysics". That term is in a sense more adequate than
"natural language ontology": ontology is often taken to be
narrower than metaphysics, dealing just with what there is (the
inventory of things) rather than, as metaphysics does, with the nature
of things (Quine 1948). However, "ontology" is
increasingly used in the broader sense of metaphysics as well,
especially when it has an empirical or applied dimension (e.g.,
"applied ontology", a field of study that involves the
practical application of ontological notions and theories to specific
domains, such as management, biomedicine, or geography), a usage this
entry will adopt as well. Also the count noun "ontology"
is better usable than "metaphysics" to denote the subject
matter of a branch of metaphysics since it comes with a plural,
allowing talk about "the ontologies of natural languages"
and "different ontologies" being the subject matter of
different branches of metaphysics.



The ontology (or metaphysics) of natural language needs to be
distinguished from the ontology of linguistic entities, words,
meanings, phonemes, etc. Sometimes the term "metaphysics of
natural language" is used for the study of the latter (Postal
2018).



Bach (1986) conceives of natural language metaphysics somewhat
differently than the present entry in that for him it is just part of
linguistics, not of philosophy. For Bach, whereas proper metaphysics
is concerned with the question "what sort of things are
there?", natural language metaphysics is concerned with the
question "what sort of things do people talk as if there
were?" Bach goes on saying 



> 
> 
> Is there Natural Language Metaphysics? How could there not? [...]
> Do the overt and covert distinctions that correspond to natural
> language categories correspond to the structure of the world? How
> could they not? But this is where linguistics stops. (1986: 593) 
> 
> 
> 



Bach then adopts agnosticism as to the ontological and cognitive
status of the entities that are posited as semantic values. The view
that natural language metaphysics is part only of linguistics has also
been adopted by Fiorin & Delfitto (2020: chap. 14), who
characterize it as 



> 
> 
> the practice of identifying and studying the qualitative differences
> between the objects in the model that are relevant to the
> interpretation of natural languages, (2020: 117) 
> 
> 
> 



whereby a model is strictly motivated by linguistic data.


### 1.2 Natural Language Ontology as a Practice Throughout the History of Philosophy



Natural language ontology as a discipline whose subject matter is the
ontology implicit in natural language is a developing discipline that,
on the view adopted in this entry, is part of both metaphysics and
natural language semantics. But in a way it has also been a practice
throughout the history of philosophy. Throughout the history of
philosophy, at times more often than others, natural language has been
used as method for clarifying *intuitions*, that is, states of
intellectual seeming that contrast, very roughly, with inferential
belief, reasoning or reflection and that have been considered the
primary evidence in philosophy (see entry on
 intuition).
 In particular, natural language has played an important role in
clarifying intuitions that bear on metaphysical issues.



Natural language has been used, for example, by Fine (2003) to
elucidate the intuitive distinction between an object and the material
constituting it While the statue may seem a distinct entity from the
alloy that constitutes it, the distinction becomes particularly
convincing when paying attention to ranges of predicates that are or
aren't meaningfully applicable to the statue and the alloy. The
statue can be said to be "defective", "well
made", "valuable", "ugly",
"Romanesque", "insured", or
"admired", even though the alloy which makes it up is not.
Some predicates may not hold of the alloy; others cannot even be
applied meaningfully to it, e.g., *Romanesque*. A philosopher
that denies an ontological distinction between an object and the
matter constituting it faces the considerable challenge of explaining
those differences in the applicability of predicates.



Another ontological distinction that has been elucidated significantly
using natural language is the distinction between objects and events.
While some philosophers take objects and events to be of the same
category and identify both with the material content of space-time
regions, others distinguish them in the way they persist through time
(endurance and perdurance, see entry on
 identity over time).
 Natural language gives significant support for the view that objects
and events relate to time and space differently. The difference is
reflected in the choice of existence predicates: *exist*
applies to objects, but *occur, take place, happen* to events
(\* *The palace existed* / ??? *happened*, *The murder
happened* / ??? *existed*)); it also reflected in the
applicability of spatial modifiers to the respective existence
predicates (*The party took place in the garden*, ??? *The
flowers existed in the garden*) (Hacker 1982; Cresswell 1986; Fine
2006; Moltmann 2020b).



Philosophers when making use of natural language in such ways to
clarify metaphysical intuitions practice natural language ontology
(even if no distinction is made yet between what is reflected in such
intuitions and what there really is, which is discussed in the next
section). They thereby generally presuppose that metaphysical
intuitions do not show interpersonal inconsistencies (see entry on
 intuitions)
 and in their linguistic manifestation, cross-linguistic differences
 (SS4.2).



Appeals to natural language of this kind can be found within different
approaches to metaphysics, as long as the philosophers in questions
take metaphysical intuitions to be a basis for developing
philosophical views. They can be found, for example, in Aristotle and
very explicitly in medieval metaphysics (Aquinas, Buridan, Ockham),
where the use of natural language examples was a common practice. It
can be found in the phenomenological tradition (Bolzano, Brentano,
Husserl, Meinong), and, again quite explicitly, in early analytic
philosophy (Frege, Twardowski, Strawson, Austin, Vendler, Ryle).
Drawing on natural language as a method of clarifying metaphysical
intuitions is also common among many contemporary philosophers that do
not explicitly engage in natural language ontology as an emerging
discipline, but just take a descriptive approach to metaphysics
 (SS1.6).
 


### 1.3 The Ontology of Natural Language and Its Relation to Reality



There are various ways in which philosophers have used natural
language to clarify metaphysical intuitions. One of the most common
ways in which philosophers draw on language concerns the denotations
of particular *types* of referential noun phrases (NPs). It is
a standard assumption in both philosophy and linguistics that
referential NPs stand for entities and predicates express properties
of entities. The types of predicates acceptable with a particular type
of referential NP are thus indicative of the ontological category of
the entities that that type of NP denotes. The types of NPs
philosophers make use of include bare adjective nominalizations like
*wisdom* when arguing for qualities or properties, deverbal
nominalizations like *laughter* when arguing for events,
modified adjective nominalizations like *Socrates'
wisdom* when arguing for tropes or particularized properties (see
entry on
 tropes),
 NPs with a relational use of *number* such as *the number
of planets* when arguing for numbers as objects, and
fact-referring terms like *the fact that it is raining* or
*the facts* when discussing the nature and role of facts
(Austin 1950; Strawson 1950). Other ways in which natural language
appears to reflect ontology and which have played a role in philosophy
will be discussed later
 (SS2.2).



The appeal to natural language in the history of philosophy was
generally based on the assumption that natural language just reflects
reality and that natural language thus provides a particularly
manifest indication for the way reality should be understood. While
the view is still present in some of the ways in which contemporary
metaphysicians draw on natural language, there is another view that
has gained prominence, and that is that natural language does not in
fact reflect the ontology of what there really is, or at least not
fundamental reality. Rather, natural language comes with an ontology
that may be quite different from what many philosophers consider the
ontology of the real.



For example, a lot of referential NPs in natural language seem to
stand for entities that many philosophers would not consider real, let
alone fundamental. These include ontologically dependent, minor, and
derivative objects such as holes, shadows, smiles, homes, problems,
reasons, advantages, and mistakes, as well as construction-driven
objects such as pluralities like "the stones in the
garden"
 (SS3.1.1),
 functional, variable, or intensional objects like "the
increasing temperature" or "the book John needs to
write"
 (SS3.1.1),
 and intentional objects of the sort "the house John was
dreaming about"
 (SS3.2).



There are also predicates of natural language that reflect notions
that diverge from corresponding "philosophical" notions,
such as the verb *exist*, which cannot convey the univocal
notion that can be conveyed by philosophical uses of the noun
*existence* (as in *the existence of everything there
is*)
 (SS1.2).



Also categorial distinctions such as the mass-count distinction, which
includes a distinction between "the water" and "the
quantity of water", "the rice" and "the rice
grains", as well as "the clothes" and "the
clothing", are nowadays not generally taken to reflect a real
ontological distinction, but, at best, a distinction at a level of
"grammaticized individuation"
 (SS3.3).



Such discrepancies motivate distinguishing two ways of pursuing
metaphysics:


1. metaphysics whose aim is to uncover the ontology
reflected in natural language or intuitions more generally, that is,
*descriptive metaphysics*
2. metaphysics whose aim is to uncover what there really
is, that is, *foundational metaphysics.*



This distinction raises important questions itself, though.



First of all, how should reality itself be understood? Does reality
just consist in what is fundamental, and if so what entities or
ontological category would be fundamental (e.g., certain sorts of
objects, properties or facts), and in what sense of fundamentality?
(see entries on
 fundamentality
 and
 metaphysical realism).
 Or does reality also include ordinary objects (which are generally
not considered fundamental), and perhaps entities ontologically
dependent on them (such as tropes and events, or even entities like
shadows and holes), and in what sense of ontological dependence (see
entry on
 ontological dependence)?
 Or does reality consist of a much greater range of entities, even
perhaps a plenitude of just anything *x* that is conceivable that
meets the conditions for *x*'s existence (Eklund 2008;
Schaffer 2009; entry on
 existence)?
 Does reality consist of a single level of being or different levels
ordered by relations of grounding or fundamentality, and would there
be a single such relation or a plurality of relations? (see entries on
 metaphysical grounding
 and
 fundamentality).
 Does reality come with a structure at all or is it an
"amorphous lump", to be carved out in one way or another
by language? Finally, should reality include a realm of mere
possibilia and perhaps nonexistent, merely intentional objects (see
entries on
 possible objects
 and
 nonexistent objects)?
 Depending on how reality itself is conceived, the ontology of natural
language may or may not be viewed as an ontology of the real (see also
 SS2.2.5).



A second question is whether the two metaphysical projects can be
pursued independently of each other. While many contemporary
metaphysicians aim to pursue
 [ii]
 without engaging in
 [i],
 Fine (2017a) argues that the two branches of metaphysics cannot be
pursued independently, but that [ii] presupposes [i]: metaphysics that
aims to figure out what there really is has to take descriptive
metaphysics or what Fine calls "naive metaphysics" or
"the metaphysics of appearances" as its starting point,
that is, the metaphysics whose aim is to uncover the ontology
reflected in our intuitions or ordinary judgments. That is because
naive (or descriptive) metaphysics provides the clarification of
the metaphysical notions that foundational metaphysics aims to explain
in more fundamental terms.



A third issue is whether metaphysics that aims to uncover what there
really is can even be pursued in the first place. There have been
various movements in metaphysics that deny that, including Kantian and
phenomenological approaches
 (SS2.1).
 In fact, natural language ontology might very well be pursued while
taking a skeptical stance toward the metaphysics of the real.


### 1.4 The Ontology of Natural Language and Truth Conditions



Some central issues in natural language ontology bear on the question
of how reality and existence are to be understood.



One of them concerns natural language ontology itself, when its
subject matter is an ontology that may diverge from the ontology of
what is considered real. How is natural language ontology compatible
with what is widely regarded as a fundamental requirement on semantic
theory, namely that of giving truth conditions? For a sentence
*S* about an entity *d* to be true or false, what makes
*S* true or false, it seems, needs to be a part of reality that
includes *d* itself, and thus *d* needs to be a real entity,
rather than part of an ontology of "appearances". There
are various options to pursue, each of which may be adopted for just
some part of the ontology reflected in natural language. One option is
that natural language displays ontological notions or items that
simply fail to be real, and thus speakers making use of them in their
utterances are in error. Second, entities in the ontology of natural
language may have the status of fictional entities, which means that a
sentence about such entities may not be able to be
"really" be true (unless it predicates a property of the
fictional entity *as* a fictional entity, with predicates such
as *is a fictional character*) (see entry on
 nonexistent objects, section nuclear and extranuclear properties).
 Third, entities in the ontology of natural language, even if not
considered fundamental, may be considered derivative, yet real, which
would allow sentences involving reference to them to be true. As was
mentioned in
 Section 1.1,
 some proponents of natural language ontology remain agnostic
regarding the metaphysical status of the items that natural language
ontology posits, as long as they are motivated by empirical
generalizations and theoretical linguistic considerations.



Another general issue, skeptically addressed in particular by Chomsky,
is whether referential NPs even have as their semantic function to be
used to refer to entities and thus whether referentialist semantics is
even possible
 (SS2.2.5).
 Not all approaches to natural language semantics in fact have as
their aim giving truth conditions (whether such an aim is set aside or
abandoned) and thus rely on referentialist semantics. Chomsky (2000)
himself takes the view that the semantics of natural language can
involve only our cognitive representation of the world and thus only
another level of syntax, not entities and their properties
themselves.


### 1.5 Ontology Reflected in Natural Language, in Cognition, and in Reasoning



It is tempting to take the ontology of natural language to just be the
ontology implicit in cognition, including perception. In fact, often
researchers pursuing natural language ontology take research in
cognitive science into account or pursue interdisciplinary research in
both areas at once (e.g., Wellwood et al. 2012; Wisniewski et al.
1996). While there are without doubt important connections and a
significant overlap, the two ontologies need to be kept distinct. To
give an example, it is generally agreed that the ontology implicit in
cognition in general, that is, the ontology of ordinary objects, is
not closed under sum formation, but rather subject to constraints of
gestalt (integrity) as well as function (Schaffer & Rose 2017).
Thus, the sum of the stuff in my room does not form an entity that
belongs to the ontology of ordinary objects and neither does the sum
of the Eiffel Tower and the Dalai Lama. But natural language appears
to allow for unrestricted sum formation with definite mass and plural
NPs and conjunctions of definite singular NPs (*the stuff in my
room*, *the Eiffel Tower and the Dalai Lama*), at least on
the dominant view on which definite plural and mass NPs stand for sums
 (SS3.1.1).
 Another example of a divergence between the ontology implicit in
cognition and in natural language is the mass-count distinction, with
choices such as the English mass noun *pasta* and the French
plural count noun *pates* hardly reflecting a cognitive
distinction
 (SS3.3).



Given the divergence of the ontology of natural language from that
reflected in cognition, how does the ontology of natural language
relate to cognitive agents? What sort of ontological commitment does
it involve? One option may be that the ontology of natural language is
the ontology a speaker accepts just when using the language. This
cannot be right, though: a speaker may just accept the ontology by
coincidence when using the language. Rather the acceptance of the
ontology of natural language has to be strictly tied to the use of
language; it has to be acceptance that necessarily goes along with the
use of language, that is, ontological acceptance *by way of using
the language*.



There is another cognitive dimension that matters for distinguishing
the ontology of natural language, namely that of intuition as opposed
to inferential belief, reasoning, or reflection (see entry on
 Intuition).
 Natural language can be used for making and denying various
ontological claims and for introducing revisionary ontological
theories. This may consist both in making ontological assertions and
in introducing expressions for the purpose of conveying a particular
ontological notion (see
 SS4.1).



The practice of natural language ontology, as it has been pursued by
philosophers and linguistics, makes a clear distinction between the
sorts of linguistic data indicative of the ontology implicit in
natural language and those indicative of an ontology based on
reasoning. Explicit metaphysical assertions are not indicative of the
ontology implicit in natural language, for example assertions of the
following sentences (whether they are widely believed or not):



(1)


a.
There are artifacts.
b.
 Objects are not events.
c.
 There are things that don't exist



No philosopher or linguist would appeal to sentences such as
 (1a, b, c)
 when arguing for an ontology of artifacts, of states distinct from
events, or of nonexistent entities. Otherwise, another philosopher or
linguists might just as well appeal to the negations of
 (1a, b, c),
 which are equally acceptable, to argue for just the opposite. Such
uses of language do not display the ontology implicit in natural
language, but rather ontological views based on reasoning, that is,
ontologies that philosophers accept when thinking about there is or
ontologies that non-philosophers ("the folk") naively
accept when thinking about what there is. The latter are the subject
matter of folk metaphysics (Schaffer 2019), the analogue of folk
physics and folk biology.



The ontology of natural language is instead displayed in other ways.
One way in which it has been taken to manifest itself is in
presuppositions of ontological categories carried by certain
predicates: *stop* and *happen* require events, and
*move* and *exist* (enduring) objects, on pain of
resulting in a category mistake (but see Magidor 2013 for a critical
discussion). A particularly important way in which the ontology of
natural language manifests itself is restrictions of particular types
of NPs to ontological categories of entities they may stand for.
'Perfect nominals' like *John's buying of the house* can
only stand for events, 'imperfect nominals' like *John's
buying the house* can only stand for facts (Vendler 1967). Bare
adjective nominalizations like *wisdom* can only stand for
qualities, and adjective nominalizations with a specifier
(*Socrates' wisdom*) for tropes; deverbal nominalizations
like *laughter* are generally restricted to events
 (SS1.3).
 Quantificational NPs like *every time* can range only over
times or situations, quantifiers like *somewhere* only over
places, and quantifiers like *somehow* only over qualities.
Other ways in which the ontology of natural language manifests itself
will be elaborated in
 Section 2.2.
 



The distinction between ontological assertions and presuppositions
goes along with two ways of accepting an ontology: acceptance though
reasoning or reflection and implicit acceptance by way of using the
language. The latter should be part of the definition of the ontology
implicit in natural language (Moltmann 2019):



(2)
 The ontology of a natural language is the ontology speakers
*implicitly* accept by way of using the language.


Note that it may very well turn out that the ontology arrived at
through reasoning is the very same as the ontology implicit in natural
language. What matters thus is the relation of agents to the ontology,
rather than the nature of the ontology itself.



The ontology of natural language is reflected not only in
presuppositions, but also in certain kinds of linguistic data that are
generally inaccessible to linguistically uninformed philosophical or
naive reflection. These are syntactic analyses of sentences that would
be unavailable to non-linguists and involve particular ontological
commitments. One example is syntactic analyses that posit silent
syntactic elements with ontological content. Thus, Kayne (2005: chap.
8) argues that the sentence *John has few books* contains a
silent (antecedent-less) occurrence of the noun *number*, which
suggests that the actual structure of the sentence, *John has few
number books*, involves reference to
a number. Another example is syntactic analyses that make use of
lexical decomposition with ontological relevance. Thus, Harves &
Kayne (2012) argue that the underlying form of the English verb
*need* is *have need*, which involves an ontological
commitment to things like needs that is not evident from the simple
verb *need* alone. Underlying syntactic structures of this sort
are posited in generative linguistics on the background assumption
that knowledge of grammar is implicit and to an extent innate. If
ontological notions go along with such structures, then they should be
just as much part of implicit knowledge as the syntactic structures
themselves, which means that they will be unavailable to rejection or
revision through reasoning.



Taking ontology to be part of the implicit knowledge of grammar may
also solve the puzzle of how it is possible for a speaker to reject
upon reflection (part of) the ontology that is implicit in natural
language while still committing herself to it through the continued
use of the language. On such a view, the implicit acceptance of the
ontology of natural language would not be a form of belief, but rather
a form of tacit knowledge on a par with that of grammar (Moltmann
2020a). This would explain the robustness of such a form of implicit
acceptance, which resists rejection upon reflection as long as the
agent uses the same language, unlike the implicit acceptance or bias
in ethics, for example, which does permit rejection upon reflection
(see entry on
 implicit bias).



Distinguishing implicit acceptance of an ontology through the use of
language from metaphysical reflection does of course not prevent the
latter to come into play *when building a theory* of the
ontology reflected in natural language. Natural language data may
provide only a partial specification of a particular ontological
notion so that metaphysical reasoning would fill in the rest--at
least on a view on which natural language ontology is also part of
metaphysics and not just linguistics (cf.
 SS1.1),
 and metaphysical reasoning may give independent support for
ontological notions reflected in natural language.


### 1.6 The Relevance of Natural Language Ontology for Philosophy



There are two general questions that arise regarding natural language
ontology as an emerging discipline. 


1. Why should natural language ontology be pursued in the
first place?
2. Why is its pursuit relevant to philosophy?



As regards
 [i],
 at least given certain general assumptions about semantic values,
truth conditions, and compositionality
 (SS2.2),
 natural language ontology is an integral part of theoretical
linguistics and thus as important to pursue as theoretical linguistics
itself. Theoretical linguistics has grown enormously over the last 70
years providing a wealth of semantic and syntactic generalizations and
theories, which permits a more systematic and accurate use of natural
language for metaphysical purposes. When pursued within the context of
theoretical linguistics, natural language ontology will also set its
own ambitions regarding universals, the alignment of ontology with
syntax, the relation of ontology to lexical semantics, and the
connections of the ontology reflected in natural language to that
reflected in cognition.



As regards
 [ii],
 there are specific reasons for a philosopher to pursue natural
language ontology. First of all, natural language ontology has an
important contribution to make to descriptive metaphysics
 (SS2.1),
 as it deals with linguistic manifestations of intuitions bearing on
metaphysical issues. In fact, natural language ontology can be
regarded a linguistically informed development of descriptive
metaphysics. 



Second, various topics in metaphysics have evolved historically around
linguistic facts, generally used as manifestations of shared
intuitions or of reality itself
 (SS1.2).
 By making full use of empirical and theoretical research in
linguistics, natural language ontology can shed a significant light on
those topics. For example, linguistic facts have played an important
role in the debate surrounding universals since the middle ages, where
questions were pursued such as whether *wisdom* is a term that
picks out an abstract universal or just its various instances. Natural
language examples play a significant role also in contemporary
discussions of abstract objects (Zalta 1983; Boolos 1998), properties
(Chierchia & Turner 1988; Bealer 1993), and types (Wetzel 2009).
Those discussions generally presuppose the view that natural language
allows reference to a wide range of abstract objects, though that view
has been challenged on the basis of other linguistic generalizations
and analyses
 (SS4.1).
 



Linguistic facts, at least since Frege (1918/9), have also played a
central role in motivating abstract propositions as truth bearers:
*that*-clauses appear to act as singular terms standing for
abstract propositions, truth bearers that are both meanings of
sentences and objects or contents of thought. Using a different range
of linguistic data from Polish, German, and French (in three versions
of the same article), Twardowski (1911) argued for non-enduring
products of acts ("claims", "judgments",
"assumptions") being truth bearers rather than
propositions, proposing a novel cognitively realistic yet not
psychologistic account of the content of attitudes as well as the
subject matter of logic.



Finally, linguistic facts play an important role in the debate about
the existence and nature of numbers. Frege's (1884) theory of
numbers as abstract objects was motivated by sentences such as *the
number of planets is eight*, an apparent identity statement
containing two apparent number-referring terms. More recent
linguistically oriented research has put into question whether
*eight* in that sentence really refers to a number rather than
keeping its "adjectival" meaning (as a quantifier or
plural property) and moreover whether *the number of planets*
in that sentence is really a number-referring term rather than acting
as a "concealed question", standing for the question about
how many planets there are (Romero 2005; Hofweber 2016).



Such philosophical debates show that when metaphysical arguments rely
on linguistic data, those data need to be subject to serious
linguistic examination, in the recognition that natural language
ontology is also part of linguistics.


## 2. Natural Language Ontology as a Subdiscipline of Both Linguistics and Philosophy



Natural language ontology as a subdiscipline of both linguistics and
philosophy raises a number of general questions. First, how does
natural language ontology situate itself within metaphysics and how is
it to be understood as a part of metaphysics? Second, how exactly does
the semantics of natural language involve ontology and thus in what
sense is natural language ontology part of linguistics? Third, what
sorts of linguistic data reflect the ontology implicit in language,
and how is that ontology itself to be characterized? In what follows,
these questions will be addressed in turn.


### 2.1 Natural Language Ontology as Part of Descriptive Metaphysics



A dominant contemporary view of metaphysics is that its subject matter
is that of fundamental reality, the task of metaphysics being, in
Plato's words, to "carve nature at its joints". If
the subject matter of metaphysics is fundamental reality, then natural
language ontology will have no place in it. There is another view of
metaphysics, however, on which metaphysics, at least in part, has as
its subject matter the general nature of things *as reflected
in* a particular range of "data". Those data may
consist in intuitions, experiences (as in phenomenology), or in
linguistic intuitions about the acceptability, truth conditions, and
inferential relations of natural language sentences (natural language
ontology). On such an approach to metaphysics, it is left open what
such data may reflect, whether it is reality in one sense or another,
a realm of actual but derivative entities, entities constituted by the
experience itself, or a realm of conceived reality. Older traditions
of metaphysics that fall under the approach include the Kantian
tradition, which deals, for example, with ontological categories, but
as preconditions of accessing the world, rather than as categories of
how things really are, as well as the phenomenological tradition
(Brentano, Husserl, Ingarden), where ontology was also pursued, but
based on how things appear (or are constituted by appearance), rather
than assumptions about a mind-independent reality.



In contemporary analytic philosophy, Strawson's (1959) notion of
descriptive metaphysics most clearly focuses on what is reflected in
data. The subject matter of descriptive metaphysics is what Strawson
calls our "shared conceptual scheme", a term indicative of
a Kantian background (see entry on
 Strawson).
 Nowadays descriptive metaphysics is more commonly taken to have as
its subject matter the ontology reflected in our shared intuitions or
ordinary judgments (since metaphysics is generally taken not to be
about representations or concepts, but things and their nature).
Strawson contrasts descriptive metaphysics with what he calls
"revisionary metaphysics", which aims to produce a better
structure of our thought (or a better ontology, as one may rather
say). Strawson does not elaborate how "better" is to be
understood; it may be meant to be metaphysics that better carves
nature at its joints, provides a better foundation of the natural
sciences, or is better able to meet whatever the standard a given
revisionary metaphysician may have in mind.



Given the Strawsonian distinction, natural language ontology clearly
belongs to descriptive metaphysics, in the sense that its subject
matter is the ontology reflected in linguistic intuitions regarding
the truth conditions or acceptability of natural language
sentences.



A distinction somewhat similar to the Strawsonian distinction between
descriptive and revisionary metaphysics is Fine's (2017a)
already mentioned distinction between "naive
metaphysics" and "foundational metaphysics".
Naive metaphysics is interested in the general nature of things,
without regard for whether they are real, with our ordinary judgments
being an important guide. As it does not distinguish between
appearance and reality, Fine also calls it the "metaphysics of
appearances". The subject matter of foundational metaphysics, by
contrast, is the ontology of what there really is, fundamental
reality. Foundational metaphysics is defined in terms of its subject
matter, not in terms of its deviation from naive metaphysics.
What is novel in Fine's distinction is how the relation between
naive and foundational metaphysics is understood: foundational
metaphysics must take naive metaphysics as its starting point (as
mentioned in
 SS1.3);
 naive metaphysics, by contrast, should be pursued without regard of
foundational considerations



Given the Finean distinction, natural language ontology will be part
of naive metaphysics. The term "naive
metaphysics" is potentially misleading, though, when applied to
natural language ontology. The ontology implicit in natural language
needs to be distinguished from the ontology of what non-philosophers
naively think there is or accept upon (naive) reflection (the subject
matter of folk metaphysics). The ontology of natural language, by
contrast, is the ontology that competent speakers of the language
implicitly accept, whether philosophers or non-philosophers and
whether they would naively or not so naively agree with it upon
reflection. For that reason, this entry stays with the better
established and less misleading Strawsonian term "descriptive
metaphysics", suitably understood.



The view that descriptive metaphysics is to be pursued without
foundational considerations also defines a methodological principle
for natural language ontology, which is not always adhered to in
natural language semantics, namely that the decision whether to posit
entities of particular ontological categories as semantic values
should not be made based on assumptions about what is fundamental or
what really exists, but rather on the grounds of the semantic behavior
of expressions.



It is not clear that natural language ontology can be pursued just as
a form of "metaphysics of appearances" without
foundationalist considerations. Considerations as to what is
relatively fundamental certainly enter decisions as to how to
understand derivative entities as semantic values. More importantly,
considerations regarding truth play a central role in semantics as
well as natural language ontology. The guiding principle for natural
language ontology may better be that of giving priority to linguistic
intuitions over foundationalist considerations when linguistic
intuitions are available.



One might think that involving metaphysical considerations in natural
language ontology means mistakenly imposing a sophisticated
metaphysics on the "folk" (competent speakers that are
non-philosophers). Clearly, however, what matters is whether the
ontology posited is the correct one, as the ontology speakers
implicitly accept by way of using language, not whether it has been
posited through reflection by the ontologist.


### 2.2 How Does Natural Language Reflect Ontology?



It is a guiding assumption of natural language ontology that natural
language reflects ontology. That is, the semantics of natural
languages involves entities of various ontological categories,
ontological structures, and ontological notions on the basis of
syntactic roles of expressions, syntactic categories and features, and
lexical words. The following will elaborate some of the ways in which
natural language reflects ontology. 


#### 2.2.1 Entities in different semantic roles



First of all, entities may play various roles in the semantic
structure of natural language sentences. To an extent, it depends on
particular semantic theories about relevant constructions or
expressions, though, what entities play what sorts of roles
 (SS2.2.2).
 


##### 2.2.1.1 Semantic values of referential NPs and variables



Most importantly, entities play a role as the semantic values of
referential noun phrases (NPs), as the things that quantificational
NPs range over, and as arguments of predicates. Referential NPs are
occurrences of NPs in sentences in which they have the function of
standing for entities. Natural language comes with a wealth of
expressions referring to or quantifying over entities, as well as a
wealth of expressions that express properties of entities (or
relations among them). The standard view is that with the utterance of
a simple sentence like *the apple is red,* the property
expressed by *red* is attributed to the entity the speaker
refers to with *the apple*.



The notion of a referential NP has played a central role in
philosophical discussions about ontological commitment; it is an
important notion in semantics and also plays a role in syntactic
theory. Names and definite NPs can serve as referential NPs, as can
specific indefinites and certain determinerless (bare) plurals and
mass nouns. Only certain syntactic positions are reserved for
referential NPs, such as the subject or the object position of
extensional predicates, as opposed to intensional predicates like
*look for*, intentional predicates like *imagine*, and
existence predicates like *exist* and *occur*. There are
various syntactic and semantic criteria for referential NPs. For
philosophers, since Frege, they include the ability of an NP to
support anaphora, to be replaceable by quantificational NPs, and to
serve as an argument of ordinary (i.e., extensional) predicates (Frege
1892; Hale 1987). For syntacticians, referential NPs also must satisfy
certain syntactic conditions: they are generally taken to have the
more complex structure of a determiner phrase (DP) rather than just
that of what syntacticians take to be an NP, NPs being able to be used
only predicatively (Abney 1987; Borer 2005).



The notion of a referential NP (or *Eigenname*
'name' as it was called at the time) already plays a
central role in Frege's (1892) philosophy of language, where it
provides a syntactic criterion for being an entity. For Frege, an
entity is what can be the semantic value of a referential NP, since
standing for an entity is the role of a referential NP in the context
of a sentence.



Entities also play a role as semantic values of quantificational NPs,
more precisely, the variables that serve to formalize them.
Ontological commitment has been tied to the role of semantic values of
variables by Quine (1948), who put forward the dictum "to be is
to be the value of a variable". This was meant to apply not so
much to natural language, though, but to regimentations of it in
formal theories of science. Yet being the semantic value of a variable
or being in the domain of a quantificational NP has become a
well-established criterion for being an entity in the practice of
natural language ontology.



Some caution needs to be applied to both the Fregean and the Quinean
criterion of objecthood. There are apparently referential NPs whose
function is not that of standing for an actual entity, for example the
subjects of negative existentials (*Santa Claus does not
exist*) and the arguments of intentional verbs (*John is
thinking about Santa Claus*). Furthermore, there are Meinongian
views according to which reference and quantification are not actually
existence-entailing but only lexical predicates are
 (SS3.2;
 Priest 2005). Moreover, there are views according to which
referential and quantificational NPs do not always range over
entities, but may just have an inferential role (Hofweber 2016).
Finally, not all quantificational NPs have the same semantic role,
ranging over entities that will also act as arguments of the embedding
predicate. Quantificational NPs of the sort *something,
everything*, and *several things* in English, which can
take the place of predicative complements as well as other
nonreferential positions, have been argued to have a nominalizing
function, introducing "new" entities into the semantic
structure of a sentence (Moltmann 2013: Chap. 3) or to be non-nominal
quantifiers, ranging over the same higher-order entities as are the
semantic values of the expressions they may replace (Rosefeldt
2008).



The notion of a referential NP also plays a central role in the
tradition of Montague Grammar, where referential NPs are taken to be
of type *e*, the type of entities (Montague 1974). Montague
himself, though, also proposed type-lifting referential NPs to the
type of individual concepts (of type \(\langle\langle e, t\rangle,
t\rangle\)). This was meant to allow for semantic uniformity with
respect to NPs that for Montague must stand for individual concepts,
such as *the rising temperature*, *the golden mountain*,
and *the mathematician John claims to be* (but see
 SS3.1.1).
 The move no longer maintains a straightforward notion of a
referential NP and thus a criterion for entities being part of the
ontology of natural language.


##### 2.2.1.2 Implicit arguments



Another role entities may play in the semantic structure of sentences
is that of implicit arguments, that is, arguments of predicates that
are not also the semantic values of referential NPs. For example, on
Davidson's (1967) influential analysis of adverbial
modification, the sentence *John walked slowly* states that
there is an event which, together with John, is an argument of
*walk* and of which *slowly* (now treated as a predicate
of events) is true 

 
\[\exists e(\textrm{walk}(e, \textrm{John}) \amp \textrm{slowly}(e)).\]


The very same considerations that lead Davidson to posit events as
implicit arguments apply to adjectives and motivate tropes as
arguments of adjectives. *John is profoundly happy* will then
state that there is a happiness trope that, together with John, is an
argument of *happy* and of which *profoundly* is true


 
\[\exists t(\textrm{happy}(t, \textrm{John}) \amp \textrm{profoundly}(t)).\]


Instead of tropes, degrees have been used widely as implicit arguments
of adjectives (Kennedy 2007; Wellwood 2015). Other implicit arguments
proposed in the literature are implicit location arguments for weather
predicates (*it is raining*) (Perry 1986) and implicit taste
parameters for predicates of personal taste (Stephenson 2007).
Implicit arguments are posited when expressions appear to act as
predicates targeting entities for which there are no overt NPs in the
syntactic context.



The semantic role of implicit arguments raises the question whether
there is a difference in ontological status between entities that are
implicit arguments and entities that are semantic values of
referential NPs. Davidson's arguments for events are generally
treated as stronger arguments for events being part of the ontology of
natural language than the fact that there are event-referring NPs,
which may have to do with the distinction between core and periphery
of language
 (SS4.1).
 There are alternatives to Davidson's semantics of adverbials,
though, which do not posit such implicit arguments (Kim 1976; Copley
& Harley 2015).


##### 2.2.1.3 Parameters of evaluation and truthmakers



Yet another important role of entities in the semantic structure of
natural language is that of a parameter of evaluation for the truth of
sentences. The standard semantic view takes a sentence to be true or
false not absolutely, but relative to a time and a (possible) world.
This first of all gives justice to the intuition that sentences can be
true or false in actual as well as counterfactual circumstances.
Moreover, there are natural language expressions that have been
considered operators shifting a parameter of evaluation. Tenses and
temporal adverbials are standardly taken to act as operators shifting
the time of evaluation and modals as operators shifting the world of
evaluation. Also conditionals are generally treated as potentially
shifting the world of evaluation for antecedent and consequent.



There is generally taken to be a difference in ontological commitment
between parameters of evaluation on the one hand and semantic values
of referential terms and implicit arguments of predicates on the
other. It is generally understood that parameters of evaluation do not
involve an ontological commitment on the part of the language user,
but are mere posits in the semantic theory, which means they have a
status as entities only in the semantic metalanguage. Parameters of
evaluation involve an ontological commitment on the part of the
language users only if there are referential expression in the object
language making reference to them, or so the general view appears to
be. For example, there are referential expressions in English
referring to times (*today, that day, that moment,* etc), but
not those referring to worlds, at least not from the core of language
 (SS4.1).
 Frege's criterion of objecthood of course does not apply to
parameters of evaluation (and, in fact, it did not even apply to
implicit arguments).


##### 2.2.1.4 Other semantic roles for situations



Situations have been considered parameters of evaluation, but they
play yet other semantic roles within particular approaches to natural
language semantics (see entry on
 situations in natural language semantics).
 Thus, in Austin's (1950) theory of sentence meaning, a speaker,
when uttering a sentence, refers to a situation that provides semantic
values for context-dependent expressions. Does this mean an
ontological commitment to situations? The answer to that question
bears on another criterion for ontological commitment, that of an
entity being part of the intended meaning of a sentence. Certainly, an
ontological commitment to situations is in place if situations must
form part of the intention of speakers when correctly using a
sentence, as is the case on that theory. This is also the case for
various roles of situations in semantic analyses of definite and
quantificational NPs, as well as E-type pronouns (Elbourne 2005). By
contrast, situations play a role strictly outside the (intended)
meaning of a sentence in Recanati's (2010) theory of
pragmatic enrichment.



In the more recent development of truthmaker semantics (Fine 2017b),
situations play somewhat similar roles to worlds as parameters of
evaluation for the truth of sentences, though truthmakers are based on
a more restricted relation of exact truthmaking between situations and
sentences. Situations in their role as truthmakers, it has been
argued, also act as semantic values of referential and
quantificational NPs, namely NPs with *case* as head noun
(Moltmann 2021a), which would amount to an explicit ontological
commitment, in both the Fregean and the Quinean sense.


#### 2.2.2 The connection between ontology and compositionality



The ontology of natural language is intimately linked to
compositionality, the chief tenet of natural language semantics. Which
entities play a role in the semantic structure of natural language
depends very much on what the semantic contribution of occurrences of
expressions to the composition of the meaning of the sentence is taken
to be. Different compositional semantic analyses of the language may
thus go along with different ontologies. This means that the choice of
an ontology may depend on the choice of a compositional semantic
theory, which in turn may depend on the choice of a syntactic theory.
Generally, the contribution of referential NPs is taken to be that of
standing for entities and the role of predicates that of expressing
properties that are applied to entities. There is a formal
alternative, though, on which referential NPs denote higher-level
functions (individual concepts) that apply to predicate denotations
 (SS2.2.1.1).
 What is most important is that for the purpose of compositionality
the contributions of referential NPs and of predicates are the same in
different types of sentences. Sometimes, different syntactic analyses
may have significant consequences for ontological issues, such as the
analysis of *the number of planets is eight* as an identity
statement about numbers (Frege) as opposed to an analysis of the
sentence as a so-called specificational sentence, conveying a
question-answer relation
 (SS1.6).



There is also a view according to which the semantic role of
expressions reflects ontology. Specifically this view has been held by
Frege, for whom predicates stand for concepts, that is, unsaturated
entities that need to apply to an object to yield a truth value (entry
on
 Frege,
 see also Liebesman 2015, who takes a critical stance).


#### 2.2.3 Ontological categories and syntactic categories, positions, and structures



Natural language may manifest ontology also in its syntactic
categories, which often appear to reflect ontological categories.
Thus, verbs are generally taken to reflect the category of events
(Szabo 2015), and adjectives the category of tropes or
particularized properties (Williams 1953; Strawson 1959). Syntactic
categories do not strictly correlate with ontological categories,
though. *Be in a hurry*, *be hurried*, and
*hurry* all are predicates seemingly standing for the same
property, but based on the lexical content of a noun, an adjective,
and a verb, respectively. Another, mere tendency of a correlation is
that of the syntactic mass-count distinction with the distinction
between stuff and individuals
 (SS3.3).



There is no agreement, at this point, as to the ontological content of
syntactic category distinctions. This is a difficult issue also
because there is a lot of cross-linguistic variation as to what
syntactic categories natural languages display (Gil 2000). Moreover,
there are theoretical developments in syntax that put familiar
syntactic category distinctions into question and require at least a
recasting of the issue. For example, in distributive morphology (Halle
& Marantz 1993; Borer 2005), lexical elements (roots) are not
associated with syntactic categories in the lexicon. Only when they
are inserted in a syntactic structure will they be associated with
syntactic categories, which means that they cannot owe any
ontologically relevant lexical content to a syntactic category.
Another example is the theory of radical lexical decomposition (Hale
& Kayser 2002), according to which a range of full verbs are
derived from combinations of a light verb and a noun, e.g.,
*walk* from *take a walk* (*take* being the light
verb and *walk* the noun). This view gives up a close
connection between events and the category of verbs, but posits a much
greater range of nouns instead that underlie full verbs.



Ontological categories in natural language may be reflected in other
ways in syntax than in syntactic categories, for example in syntactic
positions. On the recent cartographic theory of syntax (Cinque &
Rizzi 2010), syntactic positions in a sentence or an NP are associated
with a semantic content, which often amounts to an ontological
category. For example different positions for adjectival modifiers in
an NP are distinguished for modifiers of number, size, shape, and
color.



Another correlation of syntactic structure with ontology may concern
the different types of situations that serve as truthmakers for
different types of modal auxiliaries (Ramchand 2018).


#### 2.2.4 Metaphysically relevant specific expressions and constructions



Besides syntactic categories, natural language displays particular
types of expressions and constructions that appear to express
metaphysical notions. Examples are of course the copula *be*,
which conveys identity, predication, existence, and perhaps other
related notions, modals that convey metaphysical modality (*may,
must, essential, the nature of*), existence predicates that convey
existence or ways of being (*exist, occur, obtain*)
 (SS1.2),
 ontological dependence (which may be conveyed by *have* or the
possessor construction), part-whole-related expressions (Vieu 2006),
expressions of causation (*make, cause*) (Swanson 2012), and
truth (Hinzen & Wiltschko forthcoming, Moltmann 2021b). In
addition, there are various nominal constructions that serve to denote
entities of particular categories, perhaps introduced in particular
construction-specific ways
 (SS3.1)



With metaphysically relevant expressions, there is a general issue
whether they may be used as technical terms pertaining to a particular
philosophical view, in which case the expressions may be regarded as
part of the periphery of language, not displaying an ontological
notion that is part of the ontology of natural language
 (SS4.1).
 Nouns such as *existence*, *property*, *being*,
*event*, and *number* may be candidates since they can
be used with particular philosophical notions in mind, unlike the verb
*exist*
 (SS1.3)
 and copula and modal verbs, which do not permit non-ordinary,
"philosophical" uses.


#### 2.2.5 Chomskyan skepticism about reference to objects in the semantics of natural language



As mentioned in
 Section 1.3,
 the view that referential NPs stand for objects is not
uncontroversial. It has been the target of critique particularly by
Chomsky (1986; 1995; 2013), who put forward various challenges to the
traditional notion of reference as a relation to "real"
objects in a mind-independent reality. These are for the most part
cases of inconsistent property ascriptions that objects on standard
views would not be able to bear. For example, what we refer to as a
"door" could be painted, replaced, and walked through,
properties that could not be attributed jointly to material objects as
standardly understood. Another example Chomsky gives is a home, which
unlike a house may have peculiar combinations of properties: one can
own or sell a home, but not, for example paint a home. Other examples
are cities, which can be destroyed and rebuilt at a different
location, artifacts, which can undergo complete replacement of their
parts, and persons with their relative independence of the bodies.
Even terms like *water*, Chomsky (1995) argues, do not stand
for an external substance, but are individuated in part by their roles
in people's lives. For example, water can be polluted but not
H2O. Moreover, Sprite has the same percentage of
H2O as tap water, but one would not call it water, water
being individuated by function, not just chemical composition.



Against the background of traditional assumptions of how reality and
the individuation of objects is to be conceived
 (SS1.3),
 Chomsky's conclusion is that natural language does not involve
the reference relation, as a relation to "real" objects.
The semantics of referential noun phrases rather involves
lexical/conceptual structures deployed by speakers in particular
contexts to refer to particular aspects of reality. Instead of a
semantics with the (traditional) notion of external reference as its
central notion, referential terms should have an internalist
semantics, involving another level of syntactic representation, that
of lexical-conceptual structure. This view will then require a
different conception of compositionality than the standard one. Rather
than being based on objects and properties, compositional semantics
will have to do with concepts only or concepts together with mental
instructions (Pietroski 2018).



Chomsky's position, which denies that speakers using referential
NPs refer to objects (on a particular standard understanding), appears
to imply a rejection of natural language ontology as such. There are
different kinds of ontological responses to the various Chomskyan
challenges. First, one may adopt a different conception of reality.
Reality need not be conceived as a mind-independent realm of material
objects, subject to particular constraints on their spatio-temporal
location. Instead it may be taken to consist in a plenitude of
entities, including entities that are individuated by function and
purposes. Second, one may adopt non-standard notions of an object that
allow for apparently contradictory property attributions, such as
"complex objects" that obtain properties from distinct
entities of which they are composed (Arapinis & Vieu 2015) or
"variable embodiments" that inherit properties from
different manifestations (Fine 1999). A third type of response is to
revise standard views of predication by having predicates apply to
underspecified conceptual units ("dot objects"), which are
then mapped them onto real objects (Pustejovsky 1995) or to have
predication be based on particular ways of property inheritance from
parts or constituting matter (Liebesman & Magidor 2017). 


## 3. Distinctive Features of the Ontology of Natural Language


### 3.1 Complex NPs and Constructional Ontology



The pursuit of natural language ontology appears to go along with a
view of ontological pluralism according to which there is not a single
ontology, but several ontologies associated with different cognitive
or representational functions, in addition to the ontology of what
there ultimately is. The following sections will discuss cases that
appear to show a discrepancy between the ontology of natural language
and the reflective ontology of ordinary speakers, that is, the
ontology speakers naively accept when thinking about what there is, an
ontology that includes the ontology of ordinary objects. They are just
some of examples of the wealth of "derivative" or
"minor" entities that referential NPs may stand for and
that are likely to be rejected by speakers of the language when
thinking about there is. Referential NPs standing for such
controversial entities satisfy the very same criteria of
referentiality as NPs standing for less controversial entities, by
accepting the same sorts of predicates as ordinary referential NPs,
supporting anaphoric pronouns, and being replaceable by
quantifiers.


#### 3.1.1 Reference to unrestricted sums and kinds



The first case involves definite plurals and mass nouns as well as
conjunctions of definite NPs. The dominant view in natural language
semantics is that the semantics of such NPs involves an ontology of
unrestricted sums of individuals (in the case of plurals) and of
quantities (in the case of mass NPs). That is, *the things in my
garden* stands for the sum of the things in my garden, the
definite mass NP *the sand in the Sahara* stands for the sum of
the sand quantities in the Sahara, and *the Eiffel Tower and the
Dalai Lama* stands for the sum of the Eiffel Tower and the Dalai
Lama (Link 1983; Champollion & Krifka 2017; Ojeda 1993).
Motivations for that view are that definite plurals and mass NPs
exhibit standard criteria of referentiality and share predicates with
singular NPs with the same readings. Thus, *heavy* displays
readings applying to the entire referent of the definite NPs
below:



(3)


a.
 The stone is heavy
b.
 The stones are heavy.
c.
 The sand is heavy.



A sum of individuals is generally understood on the basis of a part
relation specific to plurals and distinct from the part relation
applying to individuals (Link 1979; Ojeda 1993).



If definite plural and mass NPs and conjunctions of definite NPs stand
for sums, they do not impose any restrictions on sum formation, which
means that the ontology of natural language displays mereological
universalism (see entry on
 mereology).
 Mereological universalism is generally not taken to obtain for the
ontology of ordinary objects, where sum formation appears subject to
conditions of integrity (such as having a form or boundary) that the
potential sum must fulfill (Simons 1987) or by teleological conditions
of purpose (Rose & Schaffer 2017)
 (SS1.5).
 Such restrictions need not obtain for sum formation in the ontology
of the real or fundamental, where mereological universalism is a
plausible view.



A similar issue arises with the denotation of bare (determinerless)
plurals and mass nouns such as *dinosaurs* or *water.*
Bare plurals and mass nouns in English are generally taken to be able
to act as terms referring to kinds (Carlson 1977):



(4)


a.
Pigeons are widespread
b.
 Water is transparent



Predicates of kinds include those conveying properties of the kind as
a whole, as in
 (4a),
 and those conveying properties characteristic of the instances of the
kind, as in
 (4b).
 The kind-referential status of the bare nouns in
 (4a, b)
 is supported by the usual criteria for referentiality. *Pigeons* will thus stand for a kind whose instances are particular
pigeons, and *water* will stand for a kind (substance) whose
instances are particular water quantities.



The semantics of bare plurals and mass nouns involves a particular
notion of kind: kind formation for the purpose of the semantics of
bare plural and mass nouns is unrestricted. Bare plurals like
*typographical mistakes*, *old pink buttons* or
*cheap red wine* are semantically entirely on a par with
*pigeons*, displaying the same semantic characteristic readings
of predicates. Those would hardly be considered kinds in folk
metaphysics or the ontology of the real, where not just any
instantiated (non-natural) property corresponds to a kind. 



Such a divergence also holds for qualities. In the tradition of
Aristotle's Categories (see entry on
 Aristotle's Categories),
 bare adjective nominalizations such as *wisdom* in
 (5)
 can be regarded terms for qualities, universals whose instances have
been taken to be tropes (modes or Aristotelian accidents) (Lowe
2006):



(5)
 Wisdom is better than cleverness.


As a universal, "wisdom" will have as its instances tropes
such as Socrates' wisdom or the wisdom of that remark. With bare
plurals and adjective nominalizations, English appears to reflect the
Aristotelian four-category ontology of individuals (primary
substances), kinds of individuals (secondary substances), tropes
(accidents/modes), and kinds of tropes (qualities). Like Aristotelian
secondary substances, the kinds that bare plurals stand for generally
inherit their properties from their instances (*Pigeons can
fly*) and exist only if instantiated (*Pigeons exists*
implies the existence of an individual pigeon). However, qualities as
denotations of bare adjectives are unrestricted.
*Irregularity*, *dirtiness*, and *underserved
wealth* will likewise stand for qualities, but not in any sense of
naturalness that would put them on a par with natural kinds.



The view that definite plurals and mass NPs and bare plurals and mass
nouns stand for unrestricted sums or kinds is not uncontroversial. An
alternative view that has been pursued for definite plurals is that of
plural reference, the view according to which the definite plural
*the stones* refers to each stone at once, rather than
referring to a single plurality (Yi 2005; 2006; McKay 2006; Oliver
& Smiley 2013; entry on
 plural quantification).
 There are various motivations for plural reference. One of them is
the intuition that a sentence such as
 (3b)
 is about the stones, not a distinct object that is the sum of stones.
Another motivation is the applicability of *many* and numerals
like *ten* to plurals (*the stones are many / ten*), but
not sums (?? *the group / sum of the stones is many / ten*).
Plural reference is also motivated by the way the predicates *are
some of* and *is one of* are understood. If *Genie*
is the name for the sum of Russell and Whitehead, only
 (6a)
 will be true, not
 (6b)
 (Yi 2005: 472):



(6)


a.
Genie is one of Frege and Genie.
b.
 Genie is one of Frege and Russell and Whitehead.



Similarly, quantities as denotations of definite mass NPs (*the
sand*) appear to behave neither as one nor as many and may
ultimately require a different account (Laycock 2006; McKay 2016).



Similar considerations shed doubt on bare plural and mass nouns
referring to kinds as single entities. For example, just as
 (7a),
 unlike
 (7b),
 cannot express the existence of a sum as an entity distinct from the
individuals,
 (8a)
 could not be used to make a claim about the existence of an entity
that is a possibly uninstantiated kind or property (Strawson 1959;
Wolterstorff 1970: Chap. 7), as opposed to
 (8b),
 which can be used that way:



(7)


a.
The books exist.
b.
 The sum of the books exists.

(8)


a.
 Wisdom exists.
b.
 The property of being wise exists.



There are two alternatives one might pursue for the semantics of kind
terms of the sort of bare plurals and mass nouns: first, posit
entities that fail to have properties themselves but have properties
strictly on the basis of inheritance from their instances; second,
extend plural reference to bare plurals and mass nouns, by taking them
to plurally refer to all the possible instances (Moltmann 2013: chap.
2).


#### 3.1.2 Intensional definite NPs



NPs such as *the increasing air in the balloon, the rising
temperature*, *the people that can fit into the car*, or
*the book John needs to write* appear to behave like
referential NPs and have been analyzed as standing for particular
sorts of entities, variable embodiments or variable objects (Fine
1999; Moltmann 2013: chap. 4), entities that are hardly part of the
ontology speakers in general accept when thinking about what there is.
There are alternatives to the ontological analysis, though, such as
that of Montague (Montague 1974), who took *the temperature* to
stand for a functional concept, and of Grosu & Krifka (2007), who
took the related NP *the gifted mathematician you claim to be*
to stand for an individual concept.


#### 3.1.3. Introduction of entities by abstraction



An important way of introducing abstract objects that has been
discussed in the philosophical literature is that of abstraction from
concepts (Frege 1884; Wright 1983; Hale 1987). A related view is that
of pleonastic entities introduced by "something-from-nothing
transformations" on the basis of nonreferential expressions
(Schiffer 1996). Are these strategies part of the (constructional)
ontology of natural language? On the Fregean view, abstraction is part
of the semantics of functional number terms like *the number of
planets*, which, on that view, introduce a number on the basis of
a concept (the concept planet) and the relation of equinumerosity. The
pleonastic account was originally applied to *that-*clauses and
nominals like *the property of being wise* (Schiffer 1996). The
method of introducing objects on the basis of nonreferential
expressions has been argued to be associated with the compositional
semantics of close appositions of the sort *the number eight*
and *the truth value true*, as well as other "reifying
terms" of the sort *the property of being wise* and
*the fact that *S** (Moltmann 2013: chap. 6). The use of
the abstraction strategy may serve the purpose of enlarging the domain
of the ontology of natural language by choice, if reifying terms are
part of the "periphery", not the "core" of
language
 (SS4.1).
 The introduction of entities by abstraction, though, also appears to
underlie the Kimian notion of events, as opposed to the Davidsonian
one of events as primitives (Kim 1976; Davidson 1967; Maienborn
2007).


### 3.2 Intentional or Nonexistent Objects



The view that there are nonexistent or intentional objects,
Meinongianism, is a highly controversial philosophical view (van
Inwagen 2003; entries on
 existence,
 nonexistent objects,
 fictional entities).
 But it is a view that is often motivated or defended by appeal to
natural language (Fine 1982; van Inwagen 1977; Kripke 2013; McGinn
2000; Parsons 1980; Priest 2005; Salmon 1987, 1998; Thomasson 1999),
namely sentences with existence predicates or intentional verbs such
as *look for* or *think about*:



(9)


a.
 Pegasus does not exist.
b.
 John thought about / was looking for Pegasus.



The Meinongian takes *Pegasus* in
 (9a)
 and
 (9b)
 to stand for a nonexistent object. There is an alternative view,
though, on which it is an exceptional, empty occurrence of a name
(Sainsbury 2005). Linguistic support for the Meinongian view comes
from the fact that *Pegasus* in
 (8a)
 and
 (8b)
 fulfills standard criteria for referential terms, such as supporting
anaphora and allowing for replacement by quantifiers
(*something*), as well as from the compositional semantics of
constructions with relative clauses as below (Moltmann 2016):



(10)


a.
The building John thought about does not exist.
b.
 John thought about a building that does not exist.



A compositional semantics of the relative clause constructions in
 (10a, b)
 can hardly be achieved without positing intentional objects as
arguments of both *think about* and *exist*. The task
for natural language ontology then is to develop a theory of
intentional objects that is both coherent and does justice to their
restricted occurrences in the semantic structure of sentences.



If descriptive metaphysics is conceived as the "metaphysics of
appearances", this might suggest that non-existent objects would
have to be posited as semantic values of referential NPs even with
extensional predicates. Referential NPs should reflect entities of a
certain sort whether or not they exist. However, non-intentional
predicates are existence-entailing (Priest 2005), which means that in
extensional contexts only actual entities as semantic values of
referential NPs contribute to truth conditions. Thus, *the building
is tall* is true only if the building being referred to is an
actual building that is tall. In extensional contexts, referential NPs
that turn out not to refer to actual entities better fail to have a
semantic value rather than standing for nonexistent objects. 



In intensional contexts, intentional objects have been posited also as
semantic values of anaphora, both within the context of an attitude of
a single agent and across attitudinal contexts involving different
agents (Edelberg 1986). In those contexts, intentional objects serve
as discourse referents (Karttunen 1976) and thus interact with dynamic
semantics, being individuated not just by what properties agents
attribute to them, but also by the flow of information in the
discourse (Edelberg 1986). Discourse referents in fact have sometimes
been conceived ontologically even in extensional contexts (Landman
1986), though this is not the dominant view in dynamic semantics (see
entry on
 dynamic semantics).


### 3.3 The Mass-Count Distinction



The mass-count distinction displays, in a particularly striking way, a
discrepancy between the ontology displayed by natural language and the
ontology tied to cognition or what is generally taken to be the
ontology of the real. Various criteria distinguish count nouns from
mass nouns in English. Most important is the availability of the
plural and the applicability of cardinal and ordinal numerals with
count nouns, but not mass nouns (Pelletier & Schubert 1989/ 2003;
Doetjes 2012). The mass-count distinction, it is generally agreed, has
semantic content, but there is much less agreement as to what that
content amounts to (see entry on
 metaphysics of mass expressions).
 The mass-count distinction has often been taken to reflect the
ontological distinction between individuals (*chair, door*) and
matter or stuff (*metal, wood*), a distinction that has been
cast either in terms of the notion of having a boundary or integrity
or being an atom (with respect to some concept). However, more
recently linguists have drawn attention to a number of generalizations
that indicate that the distinction between singular count, mass, and
plural nouns does not strictly go along with an ontological
distinction between different types of beings (Pelletier &
Schubert 1989/2003; Chierchia 1998; Moltmann 1997; Rothstein 2017).
First, singular count NPs seem to be able to stand for the very same
things as definite plural or mass NPs (*the (loose) collection of
stuff on this desk--the stuff on this desk, the quantity of
liquid in the container--the liquid in the container*).
Second, languages may make a choice of mass as opposed to count
without apparent perceptual differences (*rice--oats*,
*corn--peas*, *cattle--cows*). Also
cross-linguistically, the choice of mass versus count for particular
entities appears to an extent arbitrary (English
*hair*--Italian *capelli*, English
*pasta*--French *pates*). Third, there is an
important class of so-called object mass nouns, mass nouns that appear
to stand for pluralities of well-individuated objects, such as
*hardware*, *jewelry*, *luggage, staff*,
*police force*, often competing with apparent co-extensional
plural nouns in the same language (*clothes--clothing,
policemen--police force, cows--cattle,
carpets--carpeting*). Yet like other mass nouns, object mass
nouns resist numerals (\* *the three police force*) as well as a
range of other predicates applicable to plurals (*John listed the
clothes* / ??? *the clothing*, *The policemen* / ??
*the police force are / is numerous*). Whether a language
chooses a singular count, plural, or mass noun appears to an extent
arbitrary; yet the choice between mass and count plays a role for the
applicability of number-related predicates and quantifiers. The
mass-count distinction thus displays a form of "grammaticized
individuation" (Rothstein 2017), involving a language-driven
notion of unity that may diverge from the notion of unity that
pertains to cognition or what is taken to be the real structure of
things.


## 4. The Issue of Ontologies


### 4.1 The Ontology of Natural Language and the Core-Periphery Distinction



Not only metaphysical assertions are generally set aside when pursuing
natural language ontology. Philosophers when clarifying metaphysical
intuitions make use only of certain sorts of expressions (or uses of
expressions) and not others, and so for a linguist interested in the
ontology of natural language. Certainly, they will not appeal to
technical philosophical expressions or uses of expressions, that is,
(uses of) expressions meant to convey philosophical notions arrived at
by reflection, whether by philosophers or non-philosophers (the
"folk"). It is a characteristic feature of natural
language to allow for *expansion*, permitting at least certain
types of expressions to be used with a particular intended meaning and
to allow conveying new concepts through the formation of new
expressions, by means of morphological processes or syntactic
composition. These are entirely legitimate ways of using language, but
they are generally set aside when philosophers appeal to language as a
way of clarifying metaphysical intuitions. For example, Heidegger
introduced the nominalization *das Nichts* "the
nothing" as well as the verb *nichten* "to
nothing". While this is not an illegitimate use of language, no
philosopher or linguist would take the existence of the nominalization
or the verb to be evidence for there to be an entity that is a nothing
or a corresponding process or state. Likewise, the possibility of
forming, legitimately, the term *the truth value true* is
certainly never taken as evidence for truth values being entities.
Another example is the various meanings philosophers associate with
the noun *existence*. The fact that there are different notions
of existence that different philosophers endorse and associate as the
meaning of the noun *existence* does not mean that the ontology
of natural language reflects those notions all at once. As was
mentioned in
 Section 2.2.4,
 not all expressions allow for "non-ordinary" or
"philosophical" uses in that way. Expressions that belong
to the functional part of grammar generally do not, such as
auxiliaries (*have, be, can, may*), determiners, and
quantifiers, and neither does the verb *exist*
 (SS1.3).



Philosophers and non-philosophers when engaging in ontological
reflection may use or introduce expressions specifically meant to
convey their own ontological views. But such (uses of) expressions are
never considered indicative of the ontology implicit in natural
language. Yet they should come with a semantics as well, and may have
to be assigned as semantic values entities or properties, even if
fictional, in order to be integrated within a single compositional
semantics of the language. Still a distinction needs to be maintained,
in some way, between what is implicitly accepted as part of our
linguistically manifest intuitions (non-technical expressions with
their ordinary meaning) and what is added on through reflection.



The different ways in which the two sorts of linguistic data are
treated, by both philosophers and by linguists, motivate a distinction
between the (ontological) *core* of natural language (or the
use of it) and its (ontological) *periphery* (Moltmann 2020c):
only the core, not the periphery, reflects our metaphysical intuitions
and thus the ontology of natural language. Clearly, without a
core-periphery distinction, any ontological view or notion, as
reflected in particular technical (uses) of terms, would be part of
the ontology of natural language. This would mean that the ontology of
natural language would no longer reflect metaphysical intuitions and
would comprise an unrestricted range of not generally mutually
compatible ontologies.



Though the core-periphery distinction appears to have been tacitly
made throughout the history of philosophy as well as in the practice
of contemporary semanticists, the task of making it precise faces
considerable challenges. One challenge is to elaborate the distinction
content-wise, say in terms of cognitive relations on the part of
agents, distinguishing, in some way, between intuition or implicit
acceptance and inferential or reflective acceptance (of part of the
ontology). A second challenge is to investigate whether the
distinction is grounded in the grammar of language. A plausible
hypothesis to pursue is that it goes along with the divide between the
functional part of language (which includes syncategorematic
expressions, syntactic categories and features, and auxiliary verbs)
and the lexicon. The example of the contrast between
*existence* and *exist* suggests, though, that this may
be too simplified: the noun *existence* should belong to the
periphery (since it is able to convey just any notion of existence a
particular metaphysician has in mind), whereas the verb *exist*
belongs to the core, not permitting a non-ordinary use.



The question also arises whether and how the distinction relates to
the core-periphery distinction that Chomsky (1981, 1986) introduced
for syntax, where, very roughly, the core of the syntactic system of a
language represents universal grammar and the periphery exceptions and
outside influences.



Note that "periphery" is not meant to mean
"marginal" in the sense of statistically less used.
Moreover, it does not concern the kind of ontology itself: the
periphery may contain a technical use of a term which ends up denoting
the very same category or entity as a term from the core. What
matters, rather, is language-users' cognitive relation to
semantic values, whether it involves some form of reflection or
derivative acceptance rather than implicit acceptance.



Given the core-periphery distinction,
 (2)
 will need to be revised as follows:



(11)
 The ontology of a natural language is the ontology a speaker
implicitly accepts by way of making use of the *core* of the
language.


The periphery by itself imposes challenges for natural language
semantics and natural language ontology. The periphery, from a
linguistic point of view at least, is a legitimate part of natural
language (or a legitimate extension of it): technical (uses) of terms
certainly have a semantics and will reflect an ontology, even if it is
not the ontology of natural language, but one that goes beyond it. It
is part of the task of natural language semantics to in principle
allow for the semantic composition of the meaning of sentences
containing philosophical (uses) of terms.



It has been argued that there is one kind of complex expression that
generally belongs to the periphery, and that is reifying NPs of the
sort *the number eight, the property of being happy, the
proposition that it is raining*, or *the truth value true*
(Moltmann 2020c). It is a general observation that philosophers
usually stay away from reifying NPs when drawing on natural language
for motivating an ontological category. For example, Frege (1884) did
not motivate numbers as objects by appealing to the construction
*the number eight* in natural language, and he did not motivate
truth values as objects by appealing to *the truth value true*.
Rather he used expressions from the core like *the number of
planets* and *eight* when arguing for numbers being
objects, and his motivations for considering truth values to be
objects did not come from particular natural language sentences at
all. Likewise, Hale (1987) argued for properties being objects not on
the basis of terms like *the property of mercy*, but rather
simple terms like *mercy* from the core of language. Finally,
Link (1979) motivated mereological sums being part of the ontology of
language not on the basis of terms like *the sum of the
students* from the periphery of language, but rather simple
definite plurals like *the students*. The semantics of reifying
terms itself appears to be associated with abstraction involving the
introduction of an entity on the basis of a nonreferential (use of) an
expression (Moltmann 2013, chap. 6). If such an operation of object
introduction (a form of derivative acceptance) defines the content of
reifying terms
 (SS3.1.3),
 their classification as part of the periphery may become
plausible.



The core-periphery distinction in natural language ontology would be
important also for the quest for universals of natural language
ontology. Only the core reflects metaphysical intuitions, which are
generally held to not display interpersonal inconsistency (see entry
on
 intuition).
 This means that only the core, not the periphery can represent a form
of universal language-related ontology. Of course, the general
presupposition that intuitions show no interpersonal inconsistency may
be in error, and so may be the assumption that the ontology of the
core is universal rather than showing language-particular
differences.



While philosophers and linguists generally appear to adopt a
core-periphery distinction implicitly, the distinction appears
explicitly in a general hypothesis about reference to abstract objects
in natural language that has been pursued in Moltmann (2013):



(12)


**The Abstract-Objects Hypothesis**
  

Natural language does not involve reference to abstract objects in its
core, but only in its periphery.

 


The Abstract-Object Hypothesis is a particular thesis *within*
natural language ontology; it is not a methodological principle of
natural language ontology as such. This means that natural language
ontology, with (or even without) its core-periphery distinction, may
be pursued while not subscribing to the Abstract-Objects
Hypothesis.



The Abstract-Objects Hypothesis goes against the widely held belief
that reference to abstract objects in natural language is rampant
 (SS1.6).
 Based on a range of semantic and syntactic generalizations, Moltmann
(2013) argues that this view is mistaken: what appear to be
expressions in the core of natural language, referring to abstract
objects (numbers, properties, propositions, degrees, expression types)
are in fact expressions referring to particulars, pluralities of
(actual or possible) particulars, or variable objects, or else they
are expressions that fail to have a referential function in the first
place (numerals, clausal complements, predicative complements,
complements of intensional transitive verbs). The particulars comprise
tropes, including quantitative tropes (John's height) and number
tropes (the number of planets) (see entry on
 tropes).
 Only in the periphery, so the view, is reference to abstract objects
possible, for example through the use of reifying terms such as
*the number eight*, *the property of being happy*,
*the word "happy"*, or *the proposition that it
is raining.* Thus, the view is that in its core, the ontology of
natural language displays a form of trope nominalism (see entry on
 nominalism in metaphysics).


### 4.2 The Question of Ontologies



Distinguishing different branches of metaphysics goes hand in hand
with the view according to which there is not a single ontology, but
several, at least apparent, ontologies, ontologies pertaining to
language, to cognition, and to fundamental reality. But there is also
the question whether there is in fact a single ontology of natural
language. When natural language has been used to clarify metaphysical
intuitions, the presupposition was that metaphysical intuitions do not
show interpersonal inconsistencies, which means that there is a unique
ontology reflected in the relevant ways in natural language. There are
reasons to be skeptical of that presupposition. It is not necessarily
the case that there is a single ontology implicit in all natural
languages, just as there may in fact be interpersonal differences
among intuitions, which have now become the subject of experimental
philosophy (see entry on
 experimental philosophy).
 The proper subject matter of natural language ontology should thus be
the *ontologies* of natural languages. The possibility of
interlinguistic ontological differences touches touches upon the
Sapir-Whorf hypothesis and the controversy surrounding it (Pinker
1994; Hespos & Spelke 2004; Pelletier 2011). Of course, it may
turn out that the ontologies of natural languages are in fact the same
or at least that there are constraints on how the they may differ from
each other and what linguistic phenomena (of the lexical or functional
part of grammar) such differences may pertain to. Assuming a
distinction between core and periphery, clearly, if there is a
universal ontology shared by human languages, it should pertain to the
core only. Generative linguists may furthermore be interested in such
constraints, or a universal ontology, as a way of explaining how the
grammar of a language with the ontology that goes along with it can be
learned.


## 5. Outlook



Natural language ontology is just at the initial stage of developing
as a discipline of its own. The methodological issues surrounding it
still await a serious discussion, such as the relation of the ontology
reflected in language to different conceptions of reality and to
ontologies tied to other representational or cognitive functions, the
particular notion of implicit acceptance that the ontology of natural
language involves, the core-periphery distinction, the ontological
status associated with different semantic roles, the way ontological
categories are reflected in natural language given recent theoretical
syntactic and cross-linguistic research, and the different connections
of the ontology of natural language to the functional and the lexical
part of grammar.