Are universals necessary elements of any adequate ontology?
Given that the only context for this question is the broad one of a course on Metaphysics, the essay’s title question is a little ambiguous as to its specific focus of interest.
On the one hand, the term “universal” is a standard one in philosophy used to refer to what “particulars” have in common (in rough parlance). So the title question can be read as focussing on the “Problem of Universals”, and calling for a discussion of the debate over whether or not universals “exist”. On the other hand, the term “ontology” is also a standard in philosophy. Ontology is the examination of the concept of “the nature of being”, “existence” or “reality as such.” One of the fundamental questions studied by ontology is whether some categories of being (ways of existing) are more fundamental than others, and in what sense the items in those categories can be said to “be” or “exist”. The primary product of such study is the establishment of what basic categories of being or existence there might be, and what relationships might pertain between those categories. Hence, “an ontology” is a compilation of the categories of items that “exist”, and their interrelationships. An “adequate ontology” must therefore be understood to mean a compilation of categories of being (and their interrelationships) that purports to “cover the field” – to cover all entities that can properly be said to “exist” in some sense. So the title question can be read as calling for a discussion of whether or not the category of “universals” necessarily falls within this complete catalogue.
The ambiguity arises from the concealed possibility that an “adequate ontology”, contrary superficial implications, might include kinds that are not fundamental. Such an ontology would include not only the kinds of existents that “really exist” as part of the furniture of the world, but the kinds of existents that “exist” in other senses – such as, for example, fictional entities. Sherlock Holmes and Captain Kirk must both be admitted to “exist”, albeit as fictional characters. An “adequate ontology” can thus be understood as a catalogue of the kinds of things that “exist” in any sense.
What I am going to argue in this essay is that contrary to the position of the Nominalists, “universals” do in fact exist, and the category of “universals” does form a necessary element of any adequate ontology. But contrary to the position of the Realists, I will argue that the category of “universals” is not a fundamental category of the furniture of the world. It is, instead a derivative category of existents. Universals are not out there for us to discover. They are, instead, conceptual creations of our intellects.
There is some debate as to just what distinguishes “particulars” from “universals” (cf. Ramsey(1), Russell(2)).
“We cannot think of a particular thing without thinking of at least some of its properties at the same time, and when we think of a thing as qualified by universal properties we must think of the properties as particularized in the thing, so that they belong to its particular nature as well as being identical with, or at any rate resembling, qualities in other things.” [Ewing(3), pg 211]
For the purposes of this essay, I do not intend to go into this debate. I will, instead, adopt the simplifying definition that “Particulars” is the label of an ontological category for individual (unique, specific) entities that have attributes. (I mean attributes other than “existence” – if “existence” is indeed an attribute.) An “attribute” I will take as a quality, character, characteristic, property, or relation that is or can be attributed to a thing. It is therefore part of the definition of a “particular” that particulars have some sort of relationship with attributes. Exactly how that relationship is described depends on the ontological theory one adopts. For present purposes, however, I will use the terminology that particulars “have” attributes while remaining neutral as to just what the relationship is between the particular and the attributes associated with it. Every individual particular, therefore, “has” attributes. And some particulars have attributes that we would acknowledge as similar. For example two different cats (lets call them Tibbles and Parsnip), each being a unique particular, share the attributes of being cats, being furry, being on the floor, and being (say) both Calico cats. Tibbles and Parsnip also have in common that they are predominantly golden in colour. And we can agree that they are very similar in color, even though Parsnip is noticeably darker than Tibbles. Presumably, there will be any number of other respects in which we would also judge Tibbles and Parsnip as being very similar (eg. furry, cute, on the floor, and so forth).
Everyone will acknowledge that Tibbles and Parsnip are similar, or do resemble each other, in some respects. The term “universal” is used to refer to this similarity or resemblance. “Universal” is used, in contrast with “particular”, because universals can be instantiated or exemplified by many particular things (i.e. universally), whereas particulars can be instantiated only once – each particular being unique. Universals are employed in explanations of why it is that we acknowledge that some particulars are similar with respect to some attribute
The issue raised by “the problem of universals” is how to account for the general agreement that Tibbles and Parsnip have a certain similarity with respect to some attributes. Historically, the approaches taken on this issue have been divided into three camps. There is the Platonic doctrine of “universalia ante rem” or “universals independent of things”. This is also referred to as “Realism” or “Platonic Realism” about universals. It posits that universals are really existent mind-independent entities that exist outside of space-time. Resemblance of particulars is derivative of the fact that particulars participate in the universals, although the exact nature of this “participation” is often vague. Then there is the Aristotelian doctrine of “universalia in rebus” or “universals in things”. This is also referred to as “Moderate Realism” about universals. It posits that resemblance of particulars is derivative of the fact that universals exist in the particulars, although the exact nature of this “in” is often vague. According to realists of either sort, it is the relationship between the particular and the universal that explains why we perceive Tibbles and Parsnip as having similar color. Finally there is the doctrine of “universalia post rem” or “universals after things”. This is also referred to as “Nominalism”, and has been the more popular position in the Twentieth Century. Nominalists argue that what the attribute word refers to is the class of particulars that fit the term, although again the exact nature of this “fit” is often vague. “Universals” as an ontological category is unnecessary since all that exists are particulars and the words we use to talk about them.
It would be convenient if the works of each philosopher could be neatly slotted into one of these three approaches. However, from a perusal of the literature, it would seem that most philosophers actually fall somewhere in between. While attributing to others the archetypic positions, their own positions appear to blur the distinctions. H.H.Price(4), for example, suggests that there is only a terminological difference between the moderate realist and the nominalist. The moderate realists “recurrent characteristics” becomes the nominalist’s “resemblances”. Both admit that there are characteristics of objects in the world upon which the recurrence or resemblance is based. Both deny the independent existence of universals maintained by the Platonic realist.
Realists of both flavours challenge the nominalist’s view by claiming that it does not resolve the problem of universals, rather it ignores the problem. The predicate nominalism of David Armstrong leaves as unexplained just why it is that some predicates (as in this case, “is golden”) correctly apply to given particulars while others (say “is red”) do not. Quine’s resemblance nominalism leaves as unexplained why is it that Tibbles and Parsnip are members of one particular resemblance set (say “cat-ish”), rather than some other set (say “dog-ish”). Trope nominalism (Douglas Ehring and D.C.Williams) leaves unexplained just how it is that we can recognize that some tropes are similar while other are not.
One of the arguments of the realists is essentially linguistic. Consider the statement “green is a color.” A word like “green” wouldn’t be a name if there weren’t something for it to refer to. Since many philosophers maintain that the meaning of a name just is its referent, the realists can argue that there must be something that is the referent of “green”. If general words like universals are in fact names, and the meaning of a name is the referent of the name, then there must exist something that is the referent of the names of attributes. According to the realists, “universals” is the category of existing entities that are the referents of the names of attributes.
Realists maintain that we judge Tibbles and Parsnip as being similar in color because they both share a common relationship to the universal “golden”. The reason why we recognize a similarity of attribute across two or more particulars is because they share a common relationship to the universal that is the attribute in question. However, one of the challenges raised by Nominalists is precisely what the relationship is between the particulars that exemplify universals, and the universals that they exemplify. Modern realists like Russell(6) and Zimmerman(7) are generally less than clear about precisely what they mean when they claim that particulars “exemplify”, or “instantiate”, or “manifest”, or “participate in” universals. And they are less than clear on just how it is that we come to some awareness of that “manifestation”, “participation”, “exemplification”, or “instantiation”.
Realists, it is suggested, argue that “an experienced similarity between things demands for its explanation a genuine similarity of characters which may be abstracts and, as it were held in the mind apart from the things which possess those similarities”(8). Nominalists reply, it is suggested, that “if two things are alike in any feature, that merely means ‘that the mind fails to discriminate between those objects in certain respects and for certain purposes’. But this does not imply that there is any ‘real or substantial universal’ which binds these objects together, or ‘anything literally common to’ them.”(9).
One of the challenges facing both realism and nominalism, however, is the problem of boundaries. How is it that we draw the boundaries we do around the universals – generic attribute names – we identify. What is it that renders attribute A (the predominant colour of Tibbles) numerically identical to (and hence an exemplification of exactly the same universal as) attribute B (the predominant colour of Parsnip)? Theorists have come up with all sorts of explanations, the most famous and influential of which is the theory of natural kinds (cf. Quine(5)). This theory maintains that there are “natural kinds” out there for us to discover, and it is up to us to discover them. And it is up to the philosophers to provide descriptions of what it is that makes one natural kind different from another. But the natural kind theory of attributes is a realist conception of universals. Nominalists, of course, would disagree. A nominalist would argue instead that the kinds that we label are more or less completely arbitrary – a simple matter of linguistic convention. Yet both approaches leave unresolved the question of what is it that makes Tibbles roughly the same colour as Parsnip – even though they are discernably different in colour. And what is it that makes a cat different from a dog.
Neither side of this debate has proved persuasive in the 2500 years since Plato. According to Ramsey, this suggests that another approach needs to be tried:
“Evidently, however, none of these arguments are really decisive, and the position is extremely unsatisfactory to any one with real curiosity about such a fundamental question. In such cases it is a heuristic maxim that the truth lies not in one of the two disputed views but in some third possibility which has not yet been thought of, which we can only discover by rejecting something assumed as obvious by both the disputants.”(10)
Both the realist and the nominalist adopt the linguistic assumption that the meaning of a word is derived from what it designates. A name refers to and designates a single thing. Hence a name means that thing which is its designatum. In like manner, it is assumed by both, the word for a universal refers indifferently to any one of an indefinitely large class of objects. But what does it designate? Realists maintain that the word for a universal designates a particular existing universal, and thereby acquires its meaning from its designatum. Nominalists maintain that the word for a universal designates the class of objects, and thereby acquires its meaning from its desginatum.
A third alternative can be found by denying the common assumption of both the realist and the nominalist. The Conceptualist offers a third alternative by denying that the designatum of a name or a word is something in the world. Instead, the designatum of a name or a word is a constructed concept (which may or may not pick out something from the world). According to Conceptualism, resemblance or similarity is the consequence of a combination of our cognitive convenience and our bio-psychological reaction to the inputs of our senses. We recognize that our two cats are similar in color because the inputs to our visual cortex result in a similar cortical response to the sight of the cats. We judge that the two cats are similar in color because the cortical responses are similar, and the classifications of colors that we have created contain a classification called “golden” within which both those cortical responses fall. Or in briefer terms, the two cats are both golden because our concept of golden covers both colors.
The Conceptualist theory posits that what marks the boundaries of a given universal is our current cognitive purpose. Contrary to the realist approach, universals do not exist independently of how we think of them. They are not given by the world for us to discover. But the realist is correct when she maintains that the basis of the distinction between one attribute and another is in the world. There is no perceived similarity of objects which is not objectively based on real objective similarities and differences. We cannot discriminate where there is nothing in the world to discriminate. The nominalist is correct, however, when she argues that the number of possible universals is unlimited. Given any pair of randomly chosen objects, there will be at least one respect in which the two can be regarded as similar. How we choose to discriminate, when we can discriminate, is entirely up to us. Wittgenstein’s concept of a universal as a family resemblance is a case in point. The only thing that games have in common is that we choose to include them within the boundary of what we call “games”. There is a real distinction between any one game, and what is not a game. But how we draw the boundaries is up to us.
If one accepts the principle that what marks the boundary of a concept (a universal, a particular, or the referent of a proper name), is our current cognitive purpose, then boundaries can change as our cognitive purpose changes. But when it comes to dealing with the world around us, and particularly with the interactions we have with others, we have a clear cognitive purpose of cleaving those surroundings in a manner that is most conducive to our ability to anticipate how it will react to us. This is where conceptualism differs from nominalism. When dealing with the world around us, we have a clear interest in erecting boundaries around portions that are most easily predictable – lest we become lunch rather than enjoying it. When dealing with other people, we have a clear interest in erecting boundaries in the roughly the same places as do others – lest communications become totally impossible. The boundaries we erect are therefore not arbitrary, contrary to the arguments of nominalism.
The advantages of the Conceptualist thesis is that it nicely syncs with our common sense view of things. Whatever it is that we wish to regard, what we call it, how we identify it, will depend on how we are thinking about it – the sortal we choose to apply. It also means that how we view an object can change according to the context of our discussion, and our changing cognitive interests.
One of the corollaries of the Conceptualist theory of universals, of course, is that it views universals as derivative rather than fundamental entities. The existence of any particular concept is dependent on our cognitive purpose in establishing its boundaries. In a conceptualist ontology, “universals” are not fundamental mind-independent entities, they are a category of concepts. The entity known as “The world” is the only fundamental mind-independent entity. (Not even “particulars” are fundamental in a conceptualist ontology). “Universals,” like “Particulars,” are derivative and mind-dependent entities – they exist only as concepts. They both exist because and only when we create them by drawing suitable boundaries around how we react to the world around us.
So, if an “adequate ontology” must be understood to mean a compilation of categories of being (and their interrelationships) that purports to cover all entities that can properly be said to “exist” in some sense, then the category of “universals” must be accepted as part of an adequate ontology. Once we create them, concepts certainly “exist”. They may exist in the realm of mind generated objects that include fictional characters, but “exist” they certainly do. And as entities that exist in some sense, they must be covered by a complete ontology.
Notes and References
(1) Ramsey, F.P.;”Universals” in Mind, New Series, Vol 34. No 136 (Oct. 1925), pp401-407, URL=<http://www.jstor.org/stable/2249716>
(2) Bouwsma, O.K.; “Russell’s Argument on Universals” in The Philosophical Review, Vol 32. No 2 (Mar. 1943) pp 193-199, URL=< http://www.jstor.org/stable/2180585>
(3) Ewing, A.C.; “The Problem of Universals” in The Philosophical Quarterly, Vol 21, No 84 (Jul. 1971), pp 207-216, URL=<http://www.jstor.org/stable/2218126>
(4) Price, H. H.; “Thinking and Experience – Chapter 1, Universals and Resemblances” in Metaphysics: The Big Questions, Peter Van Inwagen & Dean Zimmerman (Eds.), Blackwell Publishers, Inc., Oxford, England, 1998, ISBN 0-631-20588-8. Pgs 23-40.
(5) Quine, W.V.;”Natural Kinds” ” in Metaphysics: An Anthology, Jaegwon Kim & Ernest Sosa (Eds.), Blackwell Publishing, Ltd., Oxford, England, 1999. ISBN 978-0-6312-0279-0. Pgs 233-242.
(6) Bouwsma, O.K.; “Russell’s Argument on Universals” in The Philosophical Review, Vol 32. No 2 (Mar. 1943) pp 193-199, URL=< http://www.jstor.org/stable/2180585>
(7) Zimmerman, Dean W.;”Distinct Indiscernables and the Bundle Theory” in Metaphysics: The Big Questions, Peter Van Inwagen & Dean Zimmerman (Eds.), Blackwell Publishers, Inc., Oxford, England, 1998, ISBN 0-631-20588-8. Pgs 58-66.
(8) McGilvary, E.B.;”Relations in General and Universals in Particular. I” The Journal of Philosophy, Vol. 36, No. 1 (Jan. 5, 1939), pp. 5-15 as quoted in Moore, Jared, S.;”Why a Realism of Universals?” in The Journal of Philosophy, Vol 36 No 25 (Dec. 1939), pp 684-688. URL=< http://www.jstor.org/stable/2018917>
(9) Lee, Harold N.;”Esthetics and Epistemology” in The Journal of Philosophy, Vol. 36, No. 11 (May 25, 1939), pp. 281-290 as quoted in Moore, Jared, S.; “Why a Realism of Universals?” in The Journal of Philosophy, Vol 36 No 25 (Dec. 1939), pp 684-688. URL=< http://www.jstor.org/stable/2018917>
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