This article was last modified on August 1, 2016.

What are Quine’s Views on Ontology?

Quine says much about ontology, ontological commitments, ontological relativity and related topics. Some have said that he has written almost as much on ontology as on philosophy itself. Chateaubriand, for instance, says Quine “published extensively on ontology — perhaps more than on any other specific philosophical subject.” [Chateaubriand: 41] Indeed, it would be hard to find a book by Quine or about Quine that did not cover his views on ontology in some capacity.

And one has to agree that “Quine’s work on ontology provided a basic framework for most of the discussions of ontology in analytic philosophy in the second half of the Twentieth Century.” [Chateaubriand: 41] Further, “Quine’s work has been a source of inspiration for several generations of philosophers and logicians in the analytic tradition, and undoubtedly it will continue to be a source of inspiration for future generations as well.” [Chateaubriand: 63] Indeed, at least in the field of ontology, if the term “ontology” was brought up, it had to be confirming or refuting Quine’s work, as he had covered so much ground that starting fresh was simply impossible.

Critics, such as Ilham Dilman, contend that “Quine’s whole notion of ontology is riddled with confusion”, and that Quine’s use of the word “ontology” is a misnomer. [Dilman: viii] Or, again, “that Quine’s notion of ontology is badly confused”. [Dilman: 32] Ultimately, “Quine’s concept of ontology is untenable.” [Dilman: 123] But is Dilman’s harsh criticism justified?

Alex Orenstein lays out the case of why ontology matters and why discussing Quine’s (or anyone’s) ontology is important:

“Some of the most important philosophical differences concern competing ontologies. Physicalists, for instance, have an ontology comprising physical objects, while others, like phenomenologists, deny that there are physical objects and argue that only appearances exist. The tradition problem of universals is to a large extent a dispute over the relative merits of a nominalist’s ontology, according to which only concrete individuals exist, and realist ontologies, such as that of the Platonists, which involve the existence of abstract objects as well as the concrete objects of the nominalists. [Orenstein: 23]

The Ontological Problem

Quine sums up the “ontological problem” in one short sentence: what is there? The problem is not in the question, however, but in the answer. To say “there is what there is” just does not seem to cut it. [Quine 1961: 1] This discussion was inherited from Bertrand Russell. “Quine adopted and improved upon Russell’s view of how we express ontological claims.” [Orenstein: 5] Regarding ontology, Quine was “closer to Russell and the Polish philosopher-logicians” than to logical positivism (Carnap) or ordinary language theory (Austin and Ryle). [Orenstein: 67]

“Ontological statements follow immediately from all manner of casual statements of commonplace fact”. [Quine 1961: 10] How seriously are we to take such statements? An ontology presents itself in any “is” or “are” sentence, but what does this mean? There is some debate over what Quine would or would not consider part of his or another person’s ontology, but we will return to that.

On another occasion, he said that “the question of the ontology of a theory is a question purely of the theory of reference.” This might make you wonder why discuss ontology at all, then, and instead focus on the theory of reference. But as Quine did not follow that line of thinking, we cannot either in exploring his thoughts.

Ontological Commitment

Ontological commitment can be restated as: “What are the existential commitments of a theory?” [Chateaubriand: 41] Can your philosophy be stated in nominalist terms, Platonist terms? What you believe ultimately defines what there is or is not in the world, just as what there is or is not defines what you believe.

Dilman believes that “Quine thinks that the use of any language whatever commits the speaker to some ontology” and “what ontology we are committed to depends on the language we speak.” [Dilman: 4] Or, rephrased, “each language commits the speaker to a particular ontology.” [Dilman: 32] His contention is supported by Quine’s comments in “On What There Is”:

“We commit ourselves to an ontology containing numbers when we say that there are prime numbers larger than a million, we commit ourselves to an ontology containing centaurs when we say there are centaurs; and we commit ourselves to an ontology containing Pegasus when we say Pegasus is.”

And also, worded another way,

“Classical mathematics, as the example of primes larger than a million illustrates, is up to its neck in commitments to an ontology of abstract entities.”

Dilman is concerned that this sort of casual talk of commitment has its pitfalls. “If a child, taken in by mythology, says and wrongly believes that the horse Pegasus existed, would he have admitted Pegasus into his ontology?” [Dilman: 5] Dilman says no, though he thinks Quine would have to say yes.

Quine may not hold commitment to be as casual as Dilman supposes, as he does say, “Ordinary discourse is indeed seldom meticulous about ontology”. [Quine 1992: 27] This suggests that the words of the child or layman need not be taken as anything more than idle talk without commitment. In fact, he admits as much when he says “the question of ontological commitment is parochial, though within a much broader parish than that of the speakers and writers of symbolic logic.” [Quine 1992: 28] And at other times, he speaks of languages allowing “fiction”. Common sense and ordinary language tell us we can speak about “Sherlock Holmes”, “Batman” and “Peter Pan” (or whoever else) and we know that they do not “exist” in any real sense. I can see no one asserting that there is a world where Batman exists, or that we should subscribe to an ontology where he exists. Such an ontology would be truly infinite, and therefore of little or no value — what sense is there in defending a world where every conceivable idea exists?

To me, there is a difference between claiming that ontological statements follow from casual statements, and saying that ontological commitments do. We speak of fictitious things “being” a certain way all the time, but no one would reasonably try to say they exist, outside of their idea.

Ontological Reduction

Quine sees in ontology a sense that it is important to have as many entities as needed, but as few as possible. He follows the Ockham’s razor rule in this regard. Chateaubriand phrases Quine’s reduction position as a question: “what is the most economical ontology that can be obtained for certain given purposes?” [Chateaubriand: 42] Or, in other words, “a theory T can be ontologically reduced to a theory T’ if the purposes for which T is used can be shown to be served equally well by T’.” [Chateaubriand: 54] Again, the point being that an ontology with fewer variables or entities is better than one with more variables or entities, so long as the additional information is useless.

In summary, “If we must expand our ontology to include new types of entities (let alone intensional ones), we should do so not at the outset but only after failing to find an alternative, less costly solution.” [Orenstein: 101]

Ontological Relativity

The concept of ontological relativity is a complicated one, and Quine does not help matters by switching what name he prefers to use. Besides “ontological relativity”, he has also used “inscrutability of reference” and “global structuralism”. Even “referential indeterminacy”, to further confuse matters. He developed this doctrine to resolve an “absurd consequence of the naturalistic-behavioristic conception of language” he endorses. [Gibson: 74] (Gibson clarifies that “ontological relativity” and “inscrutability of reference” are not strictly speaking identical — “relativity is… a generalization of the doctrine of the inscrutability of reference”.) [Gibson: 76]

“Quine holds that one’s ontology is relative to the language one speaks”. [Dilman: 12] Or, put another way, “our ontology is internal to the language we speak”. [Dilman: 16] Ontological relativism can also be defined by the following idea: “What counts as fact for us is relative to our conceptual scheme.” [Dilman: 113] Basically, the point is that if reference is relative, so is ontology.

If ontological relativity is true, and there is no objectivity, we have some real problems: “there is nothing independent of different conceptual schemes, no common measure, against which they can be measured.” They can only be compared by “measuring them against each other.” [Dilman: 113]

Of course, “the flux of experience or the barrage of stimulation to which our sensory receptors are continually subjected” may be objective, but if we cannot express this objectively, what good does this do? [Dilman: 116]

Between Nominalism and Platonism

An ontology regards what is, and nominalism declares that every existing thing is its own entity, each particular is unique and does not belong to a class. Platonism has a similar but opposite problem, saying that things in this world are instances of universal things in an ideal world. But while this limits all dogs to just being instances of “dogness”, the number of universals for a Platonist could be just as infinite: a dog may also have whiteness, hairiness, et cetera. For Quine, whether or not there are universals is an ontological question.

Despite being an empiricist, Quine does not identify with nominalism, the acceptance of only concrete individuals, which he defines as “a protest against a transcendent universe.” While this appeals to him on some level, as it denies the realm of Plato’s Ideas, he cannot accept nominalism in its entirety. He wrote in his autobiography that in 1932/1933 he “felt a nominalist’s discontent with classes.” But that sympathy alone would not make him a nominalist. Others who do accept such a view are Nelson Goodman and Tadeusz Kotarbinski.

Quine rightly rejects any commitment to Platonism as well, or at least attempts to. As he says, “We may say, for example, that some dogs are white and not thereby commit ourselves to recognizing either doghood or whiteness as entities.” [Quine 1961: 13] But he accepts other non-physical or abstract things, such as numbers, classes and sets. Along the same line as Platonism, Quine also rejects the idea of “unactualized possibles”. Some have used this idea to explain how we can speak about such things as mythological creatures, which do not exist. But this opens the door to an endless parade of possibles… rather than have them exist as an unactualized possible, why not simply assert (correctly) that they exist in no sense at all? [Nelson: 56]

Alex Orenstein says that “Quine is a physicalist and a Platonist”, though he does not mean this literally (that would be impossible). [Orenstein: 2] Quine’s ontology “favours concrete individuals and, where necessary, classes, whereas Russell argued for properties as opposed to classes.” [Orenstein: 5] This raises the issue of how to categorize Russell’s ontology, but such discussion is beyond the scope of this essay. Quine’s later writings include the idea that his ontology can be boiled down to one thing: “pure sets”. This, again, seems to suggest a move towards Platonism. Orenstein sums up Quine’s ontology as one of “extensionalism” (basically, the acceptance of the theory of reference), which has both the concrete individuals of nominalism and also sets. Quine is joined by Donald Davidson.

There are also intensionalists, who focus more on the theory of meaning. They accept some or all of the following: propositions, properties, individual concepts, the True and the False and sets, as well as individuals. Intensionalists include Frege, Alonzo Church, Ruth Marcus, Saul Kripke, and Rudolf Carnap.

Despite accepting numbers, classes and sets (which I feel is an error), Quine himself professed an affinity with physicalism, perhaps more so than Orenstein allows. Quine writes that even after science embraced field theory, “physicalism, reasonably reformulated, retains its vigor and validation.” [Nelson: 64] In psychological matters, Quine had a strong physicalist leaning. He endorsed behaviorism when many rejected it, and was opposed to granting “mental objects” a level of existence. He did not deny the existence of minds, thoughts, ideas, beliefs, etc. but felt they were not yet fully understood. Possibly, such things could be reduced to physical entities. [Nelson: 65] Indeed, it seems that each new medical advancement reduces the mystery of the mind and elevates the pure physical status of the brain. Quine wrote, “Mental states and events… are explained by neurology, when they are explained (at all). But their behavioral adjuncts serve to specify them objectively.” [Nelson: 66]

The Quine-Carnap Debate

Does accepting the existence of numbers make someone a Platonist? Basically, this is what Quine accused Rudolf Carnap of being, and the latter did not appreciate it. “Since Carnap does say there are numbers, while admitting that they are abstract and not limited to those we can specify, the label may seem apt,” says Soames, despite that Carnap “had consistently dismissed” Platonism “as cognitively meaningless nonsense.” [Soames: 19]

But also, does this make Quine a Platonist, a position he rejects? Orenstein calls Quine a “reluctant Platonist, admitting only as many abstract objects, such as sets, as are indispensable for the business of science.” [Orenstein: 86] Soames echoes his, saying, “Although both Quine and Carnap recognize the existence of numbers, Quine does so only reluctantly.” [Soames: 17] Is this reluctance: “Since there is no serious doubt that there are prime numbers greater than a million, there should be no doubt that there are numbers.” [Soames: 31]

The debate is especially interesting given Quine’s admiration for Carnap. As he says in The Ways of Paradox, “no one has influenced my philosophical thought more than Carnap”. (I think philosophy historians may disagree, but that is not important here.)

“Carnap’s central thesis is that ontological questions are intelligible only within a scientific framework for describing the world.” [Soames: 20] Carnap sees something’s existence as whether or not we can experience it (he is, after all, a logical positivist) and “these internal ontological questions can, in principle, be answered by appeal to evidence”, making them “empirical, rather than metaphysical.” [Soames: 20] Furthermore, Carnap approaches the question of whether or not properties exist as “either a disguised linguistic proposal or a consequence of a purely linguistic decision.” [Orenstein: 65]

Carnap had a more general problem with Quine’s views on ontology — the use of the word “ontology”. Carnap thought the term misleading: “it might be understood as implying that the decision to use certain kinds of variables must be based on ontological, metaphysical convictions”, while he personally felt that the decision “is a practical decision like the choice of an instrument.” He says the whole thing is nothing more than “pseudo-questions and pseudo-statements devoid of cognitive meaning”, as the debate between realism and nominalism does not exist for logical positivists, who have discarded realism as a meaningless metaphysics.

There may be some escape from the Platonist label, if we accept a variant definition of physicalism. Carnap defined it as the thesis “that every descriptive term in the language of science (in the widest sense, including social science) is connected with terms designating observable properties of things. This connection is of such a kind that a sentence applying the term in question is intersubjectively… confirmable by observations.” [Gibson: 106] As numbers (quantities) can be observable, one can accept numbers and be a Carnap physicalist, so long as we say they do not exist in any real sense.

Quine himself was “an avowed physicalist in the sense of being one who believes that reality can be fully described, if at all, exclusively in terms of physical-state predicates.” [Gibson: 161] But does this work with his acceptance of sets? Gibson points out that Quine accepted sets because of the nature of science… if science can do away with sets, Quine would have modified his physicalism. [Gibson: 166]

The Chisholm Problem

Roderick Chisholm suggested that we think of ontological commitment as follows: “If we know some sentence to be true, and if the truth of that sentence entails the existence of a certain sort of entity, and there is no way of rephrasing that sentence so that it does not entail that sort of entity, then it would be reasonable to suppose that entities of that sort exist.” [Corrado: 124] This sounds reasonable, I believe. But then Chisholm offers this sentence: There is something which is feared by Jones and anticipated by Smith.

Allegedly, if this sentence could not be rephrased, it leads us to commit “states of affairs” to our ontology. Or, more generally, intentional (psychological) concepts. Chisholm accepts such a thing, while Quine does not. On this matter, I would side with Quine. I fail to see how such a sentence introduces anything new to an ontology beyond the accepted physical world.

Does Ontology Exist at All?

Ilham Dilman is determined to find flaws in Quine’s reasoning about ontology, and comes to a rather big conclusion: there is no such thing as ontology. He claims “ordinary existential questions, such as whether there are kangaroos in America or rabbits in Antarctica, have nothing to do with ontology.” [Dilman: 25] Further, “there is no such thing as ontology, meaning that the idea of the philosopher as concerned with ‘what there is’ comes from confusion.” [Dilman: 25]

Dilman further calls Quine’s statement “ontology recapitulates philology” a mere tautology and meaningless, as he says “ontology turns out to have nothing to do with existence.” [Dilman: 29]

From the point of view of a physicialist, Quine’s obsession with ontology is a great waste of time and logic. That things in the physical world exist is not a matter of debate. Things like colors can be reduced to physical language, as colors are the emittance of light of a particular wavelength. The problem, of course, comes with numbers, but can easily be dismissed by saying that numbers are a mere shorthand and have no existence in any meaningful sense. To say there are “three” of something does not involve a new entity beyond the objects counted as three, just as a “bunch” of something does not mean that “bunches” exist if we agree that something can be in a bunch. Or handfuls, or any any other measurement, both formal and not.


Chateaubriand, Oswaldo. “Quine and Ontology”, Principia 7 (1-2), June/December 2003

Corrado, Michael. Analytic Tradition in Philosophy: Background and Issues American Library Association, 1975.

Dilman, Ilham. Quine on Ontology, Necessity, and Experience State University of New York Press, 1984.

Gibson, Roger F. The Philosophy of W. V. Quine: An Expository Essay University Presses of Florida, 1982.

Nelson, Lynn Hankinson and Jack Nelson. On Quine. Wadsworth, 2000.

Orenstein, Alex. W. V. Quine (Philosophy Now) Princeton University Press, 2002.

Quine, Willard Van Orman. From a Logical Point of View: Nine Logico-Philosophical Essays Harper Torchbooks, 1961.

Quine, W. V. Pursuit of Truth Harvard University Press, 1992.

Soames, Scott. “The Quine-Carnap Debate on Ontology and Analyticity”, Soochow Journal of Philosophical Studies, No. 16 (August, 2007)

Also try another article under Philosophical
or another one of the writings of Gavin.

One Response to “What are Quine’s Views on Ontology?”

  1. timur karamazov Says:

    – I like what you have written about Quine; however, I am looking forward to get something tangible on Quine’s Analytical hypotheses and a handful of meaning (something brief and to the point.

    Thanks in advance.

Leave a Reply