W. V. O. Quine, in his essay "On What There Is," argues that there are no possible entities, merely actual entities. By that, Quine means that there does not exist a realm of possibly existing entities, entities which do not actually exist but which are necessitated by our speech. This opposing view, which Quine identifies as "Plato’s beard" and originating in Plato’s Sophist, is rejected by Quine in favor of an application of Bertrand Russell’s "theory of descriptions." This theory argues that using a name (as if it belongs to something) does not therefore implicate that name’s signifying an existing entity. Rather, such a "thing" as Pegasus, can be paraphrased as a fragment of a whole sentence in which it occurs, and is therefore meaningful in context of the whole sentence without it therefore implicating anything existing, actual, or real. Quine, therefore, believes he can do away for any need for possible entities by paraphrasing all names into descriptive phrases, which by their nature are logically indifferent to the question of existence. However, is this view sufficient?

In this paper, I am arguing that Quine’s argument is in some ways sufficient; but, in some other very important ways, insufficient. Quine’s argument is sufficient in that it successfully gives us reason against the existence of some realm of possibilia; however, Quine misses some very important insights which are nevertheless implicated by our need to talk in terms of "not existing" or "non-being." Furthermore, his failure to appreciate certain insights occurs from his own misreading of Plato’s Sophist. Plato’s Sophist does not identify possibilia as its own realm of existence. Rather, Plato argues that when we say that something does not exist, we are saying merely that whatever actually exists is different than what has been stated. However, the need to understand things in terms of distinctions, or in terms of different than, leads us to the need for something which is not merely actual and immediate. We need in some way or other to understand things in terms of what they are different than, and it is this point that Quine misses in his critique of Plato, even as he correctly dismisses a realm of beings whose being is wholly not.

Therefore, my thesis is threefold. I shall argue that Quine’s critique of Plato’s Sophist is incorrect and is not applicable to the critiques Quine offers of McX and Wyman. Secondly, I shall argue that what Quine misses in Sophist sheds important light on the universal-like quality of "distinctiveness." Thirdly, I shall argue that Quine, though missing the point on "distinctiveness," is primarily correct in arguing against a realm of possibilia and that his own ontology may yet find a home for "distinctiveness." In fact, there are textual clues that suggest that Quine’s apparent love for "barren desert landscapes" is not so barren as it may seem at first glance.¹

I shall get at my main points by first considering the textually relevant points Quine makes in "On What There Is." The essay begins with an argument between Quine and a fictional opponent named McX who argues that whenever we talk about a thing, whether it actually exists or not, that that thing in some sense must exist:

On the contrary, Quine argues that McX’s position, what he takes to be Plato’s position, involves a confusion.⁴ Even if there exists such a thing as a Pegasus-idea, no one is denying that there are Pegasus-ideas when denying that they exist just as no one would confuse the real Parthenon with a Parthenon-idea.⁵ So, McX cannot have sufficient reason to conclude that a Pegasus exists from the mere fact that we have to have the "idea of one" because there is a great difference between the existence of an idea and the existence of an entity existing in time and space. Quine is accusing McX of equivocation.

Not content to rest with rebutting McX, Quine moves on to consider the case of Wyman. Subtler than McX, Wyman does not try to argue that a Pegasus must actually exist. Rather, Wyman argues that a Pegasus only differs from the Parthenon in lacking the attribute of actual existence. Instead, Pegasus, according to Wyman, has the attribute being possible.⁶ Sure, a Pegasus does not "exist," says Wyman, but it some kind of entity.

Not surprisingly, Quine dismisses this argument as one which merely gives the appearance of agreement. Having limited the word existence to the "actual," Wyman slips existence back in by considering it still to be some sort of possible entity. Rather than showing some ontological restraint, Quine claims that Wyman’s world is "overpopulated" and "offends the aesthetic sense of us who have a taste for desert landscapes."⁷ More than that, Quine picks at our inability in a universe of possibles to make any distinctions. He asks, "How many possible men are there in that doorway?" We cannot discern whether there are one or many, thin or fat possibilia, more thin than fat, whether any two can be alike, or whether "the concept of identity [is] simply inapplicable to unactualized possible."⁸

Another problem with Wyman’s account is evident when we consider what to do about contradictions. According to Wyman, or seemingly so, we would have to say that contradictions like "the round square cupola on Berkeley College" were possible entities. Wyman might argue that contradictions are "meaningless," and therefore not exactly possible entities, but Quine in appealing to "a discovery in mathematical logic" by Church argues that there could be no "applicable test of contradictoriness."⁹

Of course, all these arguments by Quine fail to disprove that there are such things as possible entities. All they do is deprive the force of the reasons offered by McX and Wyman in support of such entities. The most Quine has said is that a proponent of possible entities cannot give us any sense of what they are, or how to make them distinct. This may make them unintelligible to express, but this does not necessarily (unless you happen to believe in an ontological theory in which that is sufficient—but no such theory is considered here)¹⁰ mean that possible entities do not exist. Furthermore, it would seem that Quine would have to show that such entities serve no work. Primarily, possible entities are offered to explain how it is intelligible to say of something that it does not exist without committing a contradiction. If possible entities are unintelligible, what can be offered to solve the problem that they were used to solve?

Quine believes that applying Bertrand Russell’s "theory of descriptions" to expressions which are said "not to exist" solves the problem without making the expressions possible entities or otherwise or without making them meaningless. So, in "The author of Waverley was a poet," Quine, following Russell, paraphrases that to mean "Someone (better: something) wrote Waverley and was a poet, and nothing else wrote Waverley."¹¹ Now, no entity is necessarily affirmed by "something" when the term is used to bind the descriptive phrase. Rather, it is a general term, which is ambiguous, though meaningful. In fact, Quine urges that "their meaningfulness, at least in context, is not to be challenged."¹² However, "their meaningfulness in no way presupposes that their being either the author of Waverley or the round square cupola on Berkeley College or any other specifically preassigned objects." Rather, the statement is merely true or false. The value of the variable "something" is not determined by the phrase itself.

The question that Quine next takes up is whether all terms, like "Pegasus," can be paraphrased into descriptive phrases. Quine argues that even if a term like "Pegasus" could not be analyzed in terms of a descriptive phrase, it could artificially be translated as a predicate or verb expression like "pegasizes."¹³ And, although, Quine admits that that might commit us to the existence of attributes, or universals, he says that that is not the point of contention between Wyman, McX, and himself. Thus, he concludes:

The problem with Quine’s argument is that it misses the mode by which we distinguish a being’s actuality from a thing’s not existing, or rather, the mode by which we determine one descriptive phrase has a true value from that which has a false value. This, I think, is what Plato actually has in mind in Sophist when he says that "that which is not in some sense must be." Because Quine misses this point, his own analysis of the situation fails to illuminate a critical point that can take us, if not from a desert landscape, far from one which the beings in that landscape are so uninteresting. To get at this problem, let us look briefly at what Plato actually says in Sophist.

Plato’s Sophist is a work searching for the nature of the sophist, who becomes very difficult to pin down, because he is something of a cheat hiding among the things which really are not. The problem, as we have seen, is how it is possible to treat nonexistence as if it really existed. For the Eleatic Visitor, in finding the sophist, the problem is nearly the opposite. How is it possible to find the sophist’s nature if he can retreat into the realm of nonbeing and therefore force us into verbal conflicts whenever we claim to have found him?¹⁶ If we say that he peddles in false beliefs, how do we claim that false beliefs really exist when their nature seems rooted in nonbeing? So, in that context, the Eleatic Visitor urges to Theaetetus that they must examine these issues further, "and insist by brute force both that that which is not somehow is, and then again that that which is somehow is not."¹⁷

It is clear that texts like the previous one lead Quine to identify Plato with McX, calling his position Plato’s beard. In several places in the text, Plato urges that that which is not must have some share in that which is because everything in some sense must be.¹⁸ However, Quine is making Plato’s point superficial. The immediate clue that Quine is making a strawman of Plato is that Plato’s very purpose is to discredit the sophist, and the sophist is one who makes all things alike seem as though they may or may not be—a "kind of cheat who imitates real things."¹⁹ So, whatever Plato meant in saying that that which is not must in some sense be, he surely did not mean to confuse a Pegasus-idea with a real Pegasus, or to say that being and non-being existed in the very same sense.

Plato means to suggest that the nature of that which is not is wrapped up entirely in the relation of being different than being rather than contrary to it. Plato’s solution to the riddle that Quine raises through McX is to deny that words like "not" or prefixes like "non-" mean the same as "contrary" or "opposite":

However, if this is true, why say at all that that which is not in some manner exists? Why not say with Quine that such things can be explained away as descriptive phrases bound by variables? If we are not saying that that which is not entails anything like an entity, what are we saying that it is? One might be tempted to agree with Quine and say that this is no more than a dispute in semantics. If what Plato means is not that "fat people" exist in doorways in some real sense, but merely to say that it is other than the truth, or is false, to conclude that there is at least one person in this doorway who is also fat, then there does not seem to be much of a disagreement. In some sense, I think this is right. The dispute that Quine makes with Plato is in some sense overstated; but, nevertheless, I still think a dispute may be lurking there nevertheless.

Plato, I think, insists on giving that which is not some share in that which is because I take it that he believes that the conclusion that something is different than or is other than requires that each thing that is must be in some way or other distinct in order to be. So, for example, my door has hinges and screws. If hinges were not distinct from screws, they would not be hinges. Being different than a screw is in some way necessary to the very being of the hinge. And, if this overstates it,²³ surely being different than something is necessary to being a screw or being a hinge or being a doorway. In that way, I think Plato is onto something.

Quine is not onto it. Let us look again at his application of Russell’s theory. Pegasus can be paraphrased into a descriptive phrase bound by a variable which in no way presupposes existence. Ultimately, the phrase either has the value of being true or being false. However, what it is to "be true" or "be false" is left unanalyzed. "There is at least one thing that pegasizes" whose value is false. When we ask what that means, I suppose we might be answered, "There is not at least one Pegasus." This sheds little light on our judgment or on what we mean. However, if Plato is correct, then distinctiveness belongs to the very nature of what it means to be something, and therefore nonbeing.

I made a note above that Quine is likely to object to the subjunctive mood that is used in making distinctions. When we say that there are "no fat people" in the doorway, we seem to be saying something like, "The doorway is different than it would be if it had fat people." I think Quine would object to this because subjunctive conditionals seem to suggest more spooky entities, a way of slipping the possible entity in through the back door. Furthermore, in an essay entitled "Natural Kinds," Quine suggests that the maturity of our science involves removing ourselves from the need of subjunctive conditionals as we reduce things into more basic kinds (eventually dissolving our needs for kinds at all). Presumably, rather than needing to make distinctions based on understanding them in terms of some subjunctive condition, we should be able to rise above that as science advances.

For a priori reasons, I am convinced that Quine is wrong and that we will forever need to make distinctions in terms of something that is different than or is other than what is actually and immediately present. Again, let us consider screws and hinges. Let us even go so far as to say that what we mean by "screws" is primitive and basic such that hinges could be explained and differentiated in terms of screws but that screws could be explained merely in terms of themselves. I wish to claim that everything in some manner or other behaves like a hinge, such that it requires some principle of distinctiveness in its very being. This is not to say that because hinges are "not screws" that its not being a screw implicates that screws are a part of its being. It is merely to say that hinges are different than screws, and there needs to be some ontological difference in order for hinges to be. But, what do we do in the case of screws? What do we say that they are? Well, "They are just screws; it doesn’t get any simpler than that." The assumption here is that what we are looking for is a simpler kind in order to explain screws. This could not be further from the truth. We are merely looking for a principle of distinction. So, even if screws are as simple as anything possibly can be, we would still seek to understand screws and their simplicity in terms of understanding what is not simpler or what is different than primitive. The point in all of this is that there is not merely a stuff which is "stuff par excellence" and whose entire essence can be explained in terms of that stuff. If we reduce the world to one thing, we merely get indistinguishable soup, or a red square without background, or a contradiction.

So, if this argument is correct, then Plato’s suggestion that that which is not in some sense is, suggests that the is not, or the is different than, or is distinct belongs to the very nature of what it is to be something without therefore becoming an entity unto itself. It is not McX’s argument because it is not claiming that non-being has any kind of independent ontological status. It is also not Wyman because it is not claiming that there are such things as possible entities. Instead, it is claiming that distinctiveness in some sense is because it belongs to the very nature of each and every thing that is. Have we stumbled on a universal? That is, even if Quine is correct in his insistence that our universe is inhabited only by actual entities, have we nevertheless found that they participate in something called "distinctiveness"?

I think we should be wary of calling "distinctiveness" a universal for several reasons. First of all, if it is a universal, it is a very odd universal. If all things have in common "distinctiveness," then it is very strange because the very nature of "distinctiveness" would be that it makes things different from each other. It is odd to say that all things have in common a principle which makes them different. It may be that the whole dichotomy of universals to particulars turns out to be somewhat false, and just as objects contain within them a principle of "distinctiveness" it may be that "distinctiveness" is itself something which requires particular species of expression.²⁴ Secondly, many authors argue that simply because x is distinct and y is distinct, it does not therefore suggest that there is any universal called "distinctiveness."²⁵ All that simply suggests is that "x is distinct" is a primitive fact that happens to be a fact of each and every thing. It is even a primitive fact of primitive facts, I suppose. However, I have a tendency to think that in this case that this is a kind of word mongering. If all things were red, it would not suggest any such thing as "redness." It would be an accident of our universe, and I could understand the insistence of a primitive fact. However, in this case, "distinctiveness" is a necessary condition of what it is to be. It is not merely that we observe a screw and it happens to be distinct, etc. It is an a priori condition of being at all that it be distinct. Is this condition a universal or a primitive fact? I do not think it matters, but it should matter that this is quite a bit different than the case of "redness." Nevertheless, for a final reason, we should be wary of calling "distinctiveness" a universal. Universals are sometimes said to subsist in themselves, but it is clear that "distinctiveness" also depends upon having distinct particulars. Therefore, although there seems to be something "universal-like" in "distinctiveness," I think we should be wary of what to call it.

Although there are several reasons we need to be wary without more examination of calling "distinctiveness" a universal, I think there is great value that has been shed on the nature of the "not" in its relationship to "being" that has been too rashly dismissed by Quine in this work. The value applies to the desert landscape. When I look and see that rare cactus on the desert and ascertain that it is not Pegasus, I understand that cactus stands out distinctly, that it is not something else. Even if I am somewhat unconscious of my distinction, I nevertheless usually phrase it in terms of a sentence. And, even if I don’t, as in the case of young child pointing and saying "cactus," I am implicating distinction. The world does not reduce to cactus for me. It is something as different than something else, whether they be mere ideas, or screws, or hinges. To say that in the desert, that it is true that there is one, does not relegate "true" to an empty fact. The value of "true" and of "false" is wrapped up in this notion of "distinctiveness," and to that extent, cannot be divorced from some ontological consideration of that which is not. However, it does so in such a manner that Quine should approve because it does not posit any new universe of entities.

Quine, however, shows hints that his nominalism, his love for barren desert landscapes, is not so extreme, although his writing suggests that he only has a practical application for anything like a universal. At one point, Quine concedes that if there are terms which can only be paraphrased away as predicates that it might commit us to universals. He dismisses the point as irrelevant to the argument, saying, "Neither we nor Wyman nor McX have been contending thus far, about the being or nonbeing of universals, but rather about that of Pegasus."²⁶ Quine is right about its irrelevance; however, it makes one wonder in this case if he would be open to a universal of "distinctiveness," which although it does not bring in Pegasus or "pegasizing," it does bring in some role for that which is not to in some sense be. Other texts, however, suggest that Quine would allow no such role for universals. Already, we have mentioned his work "Natural Kinds" in which he says "that it is a mark of maturity of a branch of science that the notion of similarity or kind finally dissolves, so far as it is relevant to that branch of science."²⁷ I have trouble seeing how that would not apply to the need for distinctions as well. Furthermore, later in "On What There Is" Quine suggests that the use of myths may have some pragmatic value for us, even if we may ultimately be able to do without them.²⁸ Such sentiments are echoed by Daniel Dennett in an essay entitled "Intentional Systems" where he argues that although it may be possible to give a physicalist account of everything without any explanation beyond bare physical entities, it is often very useful for us in our assumptions to assume as if a mythical entity existed. Thus, when playing chess on a computer with a chess-playing computer, it is more useful for us to pretend as though the computer were actually playing chess than to figure out the entire physical structure of the computer.²⁹ Likewise, in Quine, I suspect that he would argue that "distinctiveness" is a pre-scientific, though pragmatically useful, concept that may help us understand the nature of entities, but that its being is merely pragmatic. In truth, for Quine, it is reducible by some means or other into a more preferable scientific paradigm. And, although in "Two Dogmas of Empiricism," Quine’s scientific paradigm is also in some sense replaceable, it is the most useful one we have by and large.

My argument, however, calls on Quine and other neo-pragmatists to take a much stronger line. "Distinctiveness" is not merely a pragmatic concept, it is a necessary foundation of the being of any thing and irreducible by its very nature into a fundamental physicalist approach. The very meaning of the term resists such a reduction. If we look carefully at what we are affirming when we affirm "Parthenon," we are not affirming in a vacuum. The distinction is made in context always in terms of what we can conceive "otherwise." The otherwise, not being an actual thing unto itself or really a thing at all, is a species of logical necessity and has a merely relative existence to the actual but is itself a necessary component of the very being of the actual.

The paper demonstrates a threefold thesis. First, it demonstrates that Quine’s critique of McX and Wyman are not applicable to Plato. As we saw, although that which is not in some sense exists for Plato, Plato is neither guilty of confusing the Pegasus-idea with Pegasus nor with identifying that which is not with being a possible entity. Rather, that which is not exists in some sense in terms of being different than or other than. It exists because that which is must have some principle of distinction in order to be. Secondly, the paper demonstrates that what is missed is the universal-like quality of distinctiveness. Such a quality would help keep us from the vague and unhelpful emptiness that the values "true" and "false" take when merely applying Russell’s theory such terms as Pegasus. It is not that Quine is necessarily wrong in explaining away possible entities in terms of a descriptive phrase. In that, I suspect that he and Plato actually agree. The problem is that it misses the more substantive ontological issues at stake raised by someone who might argue that nonbeing plays some role in being.³⁰ Thirdly, this paper demonstrates very early on and throughout that Quine is correct that there is no separate universe of possibilia and that his own ontology should have no reason to reject what I have said necessarily. Nevertheless, textual evidence from other sources suggest that Quine likely would reject what I have said because of his prejudice toward some sort of physicalism. The only solace that Quine is likely to give me is a pragmatic place. I think that this pragmatic standing understates the issue, and I still contend that he need have no issue with the proposal.

This paper raises many more questions that go beyond its immediate scope. Is "distinctiveness" a universal? What sort of sense can we make of "distinctiveness" and "identity" in and between objects? What is the relationship between "logical necessity" and "physical necessity"? Is logic reducible to physics? If physics is reducible to logic, as I seem to suggest, is logic itself reducible within itself? There are indefinitely more questions raised. However, what this paper does is make the questions important. If we leave Quine as the final authority on what to do with "nonbeing," we shall not be left with much. The sole role of philosophy will be to offer paraphrases that may be of some aid for scientists in conducting quantifiable experiments. However, this is shirking a great responsibility to look at what we have left unsaid. Quine dismisses some very poor arguments on behalf of possibilia but leaves unsaid the very important principle of distinctiveness, a principle which brings us back to the ancient questions of philosophy that Quine thought he and science had been able to rid themselves. However, I think I have at the very least raised issues which should broaden the scope of ontology beyond its mere emphasis that we are on a desert landscape to the notion that even desert landscapes are distinctive and interesting.

¹ However, I think Quine is still a nominalist. What will come out is that universals may have some pragmatic value. Nevertheless, they may have some work to do.

² W. V. Quine, “On What There Is,” in Properties, edited by D. H. Mellor and Alex Oliver, (Oxford: Oxford University Press, 1999), 74.

³ Ibid., 75.

⁴ Ibid.

⁵ Ibid.

⁶ Ibid.

⁷ Ibid., 76.

⁸ Ibid.

⁹ Ibid., 77-78. I am not clear what this argument is, and Quine does not make it explicit. For the sake of this argument, I am not challenging it. My guess is that without meaningful contradictions we would lack any meaningful way to distinguish a contradiction from what is not a contradiction.

¹⁰ I happen to hold such an ontological theory, but sometimes it is more effective to be less ontologically controversial when it is not particularly relevant to one’s main point.

¹¹ Quine, 78.

¹² Ibid.

¹³ Ibid., 79.

¹⁴ Ibid.

¹⁵ Frank Jackson argues this in an essay from 1977 entitled “Statements About Universals.” In this article, Jackson considers why “Red is a color” does not have a Quinean paraphrase.

¹⁶ Plato, Sophist, translated by Nicholas P. White, in Plato: Complete Works, edited by John M. Cooper, (Indianapolis: Hackett, 1997,) p. 257, (236d-247a). In this text, the issue is what one is to say false believing is. If one is unable to say, then, one will not be able to give an account of the sophist who is peddler of false beliefs. We might also note that in Quine’s work it is important for him to give an account of contradictions. The point in both works is that we figure out what they are without falling into the traps devised by those (like sophists) who are fond of verbal conflict.

¹⁷ Ibid., 262 (241d).

¹⁸ Notably, we find the worry expressed in 236d-237a. We find it explicitly stated in 241c and 241d and again in 256d-e. Again, it is reiterated in 257b-c, again in 258-260.

¹⁹ Ibid., 255 (234d-e).

²⁰ Ibid., 280 (257b-c).

²¹ W. V. Quine, “Natural Kinds,” in Metaphysics: An Ontology, edited by Jaegwon Kim and Ernest Sosa, (Oxford: Blackwell Publishers, 1999), 238-239.

²² And, of course, it is a lie of diet magazines and overpaid nutrition experts that we really have such entities as "fat people.”

²³ It may overstate it because it may not be necessary for a screw to be distinct from a hinge in order to be a screw, for instance. However, something about a hinge or a screw must be distinct if they are things at all.

²⁴ We get at the heart of my Master’s Thesis, Universality and Particularity: Toward a Coherent Rationale for Pluralism (Toledo, OH: The University of Toledo, 2000), that there are no bare particulars, nor any pure universals, that instead, any and every thing does and must function either universally or particularly. To be is to involve relationship between universal and particular functions. I go at great lengths to disprove that there are independent particulars and independent universals.

²⁵ We read one such author in Michael Devitt. Ultimately, I am not very worried in this paper about settling this issue. I think it is important, however, to see that “distinctiveness” has a binding character in a way that “redness” does not. So, even if we reduce “distinctiveness” to be the same as “is true for all n cases,” we will be saying that it will be true for every future n as well. This necessary character is not, therefore, wholly reducible to the fact but is a precondition of that fact.

²⁶ Quine, “On What There Is,” 79.

²⁷ Quine, “Natural Kinds,” 235,

²⁸ Quine, “On What There Is,” 87-88. Quine’s thoughts also echo here another classical work, his “Two Dogmas of Empiricism.”

²⁹ Daniel Dennett, “Intentional Systems,” in Metaphysics: Classic and Contemporary Readings, edited by Ronald C. Hoy and L. Nathan Oaklander (Belmont, CA: Wadsorth Publishing Co., 1991) 226-228. In a recent book entitled Darwin’s Dangerous Idea, Dennett carries this point to evolutionary science. It is not as if natural selection actually picks out those traits which promote the survival of the species. In fact, physically, Dennett argues that natural selection is a mindless algorithm, an enigma working against the third law of thermodynamics—that the universe tends toward entropy. However, in order to make predictions, we are extremely successful in our predictions if we pretend as if nature makes selections. So, interestingly enough, although nature shows no evidence of teleology, it is very useful for us to act as if it did, according to Dennett.

³⁰ We might also note Hegel, and perhaps Heidegger. Also, as we noted earlier, Quine’s dismissal of these issues suggests that his own argument merely raises a strawman.

Dennett, Daniel C. Darwin’s Dangerous Idea. New York: Simon and Schuster, 1995.

…….. “Intentional Systems.” In Metaphysics: Classic and Contemporary Readings.
Edited by Ronald C. Hoy and L. Nathan Oaklander. Belmont, CA: Wadsworth Publishing Co., 1991, 225-233.

Devitt, Michael. “’Ostrich Nominalism’ or ‘Mirage Realism’?” In Properties. Edited by
D. H. Mellor and Alex Oliver. Oxford: Oxford University Press, 1999, 93-100.

Jackson, Frank. “Statements About Universals.” In Properties. Edited by D. H. Mellor
and Alex Oliver. Oxford: Oxford University Press, 1999, 89-92.

Macdonald Jr., James S. Universality and Particularity: Toward a Coherent Rationale
for Pluralism. Toledo, OH: The University of Toledo, 2000.

Plato. Sophist. Translated by Nicholas P. White. In Plato: Complete Works. Edited by
John M. Cooper. Indianapolis: Hackett Publishing, 1997.

Quine, W. V. “Natural Kinds.” In Metaphysics: An Anthology. Edited by Jaegwon Kim
and Ernest Sosa. Oxford: Blackwell Publishers, 1999, 233-242.

…….. “On What There Is.” In Properties. Edited by D. H. Mellor and Alex Oliver.
Oxford: Oxford University Press, 1999, 74-88.

…….. “Two Dogmas of Empiricism.” In From a Logical Point of View. New York:
Harper and Row, 1971.