Quine's Critique of Intensions and Propositions

          At the close of his "Foreword" to Quine's A System of Logistic Whitehead commented that logic prescribes the "shapes" of metaphysical thought.  The logic under consider­ation of course was that in Whitehead and Russell's Princi­pia Mathematica, and the metaphysics that is “shaped” by the Russellian syntactical categories - giving the existential claim to the quantifiers - is nominalism.  There was probably no expositor of this logic that both illustrated and advocated Whitehead's comment more consistently than Quine.  For more than a decade after System of Logistic Quine published a number of articles which describe how the Russellian symbolic logic and specifically how its theory of quantification enables the user of the logic to exhibit explicitly his ontological commitments, the shape of his metaphysics.  The user's ontological com­mitment to the kinds of things he believes exists, is exhi­bited by the variable, the symbol that is bound by either the existential or the universal quantifier.  The term "var­iable" in this context has a distinctive meaning that it does not have in mathematics.  In his "A Logistical Approach to the Ontological Problem" (1939) reprinted in Ways of Paradox (1966) Quine expresses the role of logical quanti­fiers with the memorable refrain: To be is to be the value of a variable.  This means that what entities there are from the viewpoint of a given discourse in the logic depends on what symbols are accessible to binding by quantifiers to become variables in the symbolic logic, and a shift from one discourse to another may involve a shift of ontology.
          In 1947 Quine published "On Universals" in Journal of Symbolic Logic and "Logic and the Reification of Universals" in From A Logical Point of View (1953).  In these papers he describes how the nominalist and realist views toward the historic problem of universals are expressed in the Russellian notation.  The nominalist view is that only individuals exist, and it is expressed in the Russellian notation by limiting the quantifiers to ranging only over symbols refer­encing individual entities.  On the other hand the universalist view affirms that attributes or properties exist.  In the Russellian notation the existence of attributes is ex­pressed by placing predicates within the range of quanti­fiers.  For this reason Quine calls the universalist view the "Platonist" view, and he calls the attributes "abstract entities.”  Or when the abstract entities are said to exist in the human mind as meanings or concepts, Quine calls them "mental entities.”  The Russellian logic thus imposes a dichotomy that reduces both realism and conceptualism to distorting caricatures that philosophers since Plato have dismissed.  The notational role of the quantifier is referential, such that whatever type of symbol may assume the role of a variable bound by a quantifier, thereby assumes the role of referencing an entity.  Ostensibly Quine's purpose is not to advocate one or the other ontological thesis, but to advocate the role of the quantifiers as making a philosopher's ontological commitment explicit.
          Quine has his own view on the issue of universals.  In 1947 he co-authored with Nelson Goodman "Steps Toward A Constructive Nominalism" in The Journal of Symbolic Logic.  Unlike most papers appearing in academic journals, this article was not so much an analytical paper, as it was a kind of manifesto advocating a nominalist programme for applying the symbolic logic.  Quine has denied that he is a nominalist, because he accepts the existence of classes, which he views as a kind of abstract entity.  And he accepts the existence of clas­ses, because he could not eliminate them in the logistic reductionist programme.  But he denies that descriptive predicates have any signification with a foundation in reality, and offers no explanation as to why classes are anything but arbitrary collections.  Typically nominalists do not reject classes.  What they reject is that there are either mental concepts or real attributes that are the basis for classes, and they view classes as merely collections of entities that are referenced by terms.  Thus notwithstanding Quine’s attempt to separate his views from nominalism, he is a de facto nominalist, because he explicitly rejects the existence of such abstract entities or mental entities as properties, attributes and intensions, such as are propounded not only by Carnap but also by the majority of Pragmatist philosophers today.  Today philosophers of science investigating scientific revolutions and also those developing computational systems have come to accept the existence of a three-level cognitive semantics of words, intensions and extensions, instead of a two-level referential semantics of only words and extensions.  Nominalists are always troubled by coreferential terms having the same extension but having different meanings or intensions.  One reason that Quine rejects these latter types of abstract entities is that they can be eliminated from the logistic reductionist programme as he construes it.  The second reason is that he denies that Carnap's intensions can be treated extensionally, as Carnap attempts to treat them by relating them to classes by analytical statements, a type of statement that Quine rejects.
          In "Five Milestones" Quine notes that the first of the five turning points in the history of empiricism, the shift from ideas to words. In his Word and Object he calls this shift “semantic assent”, which he advocates because philosophical discourse is carried into a domain where participants are better agreed on the objects, i.e. the words.  In “Five Milestones” he says that the shift originated with the medieval nomi­nalists. He argues against the reification of univer­sals, and says that affirming the existence of abstract or mental entities is due to a common confusion, in which descriptive predicates are given a referential function that is properly had by bound variables.  In "Ontological Relati­vity" he describes this error as a case of the copy theory of knowledge, which he says is an uncritical semantics.  He ridicules this error as the "myth of the museum" and the "fantasy of the gallery of ideas", by which he means that words are mistakenly understood to be labels for ideas or meanings, as though they were exhibits.  He views the con­fusion between names and descriptions to be a particularly pernicious philosophical error, and he maintains that Russell's theory of descriptions offers the way to avoid it.  This is the technique used by Russell in his "On Denoting" in Mind (1908).  In his "On What There Is" (1948) reprinted in Logical Point of View Quine says that Russell's theory of descriptions enables the philosopher to transform names into predicates, such that names should not be taken as an onto­logical criterion for deciding what is real.  The correct criterion for determining the ontology of a language is the use of the quantified symbol or variable, so that predicates are not confused with names, and no claims are made to the effect that predicates name entities, unless the predicates are explicitly quantified.
          Closely related to the first milestone, the second is the shift of semantic focus from terms to sentences.  In "Five Milestones" Quine explains that the meanings of words are abstractions from the truth conditions of the sentences that contain them, and that it was the recognition of this semantic primacy of sentences that gave us contextual defin­ition.  Quine traces the development of contextual defini­tion, which he calls a revolution in semantics, to Jeremy Bentham's technique of "paraphrasis", which is a kind of paraphrasing or circumlocution.  If Bentham found some terms convenient but ontologically embarrassing, contextual defini­tion enabled him in some cases to enjoy the services of the term, while disclaiming its denoting.  In "Russell's Ontolo­gical Development" (1966) reprinted in Theories and Things (1981) Quine joins Ramsey's characterization of Russell's theory of descriptions as a paradigm of philosophical analy­sis, and he says that our reward for the paraphrasis technique is the recognition that the unit of communication is the sentence and not the word.
          In his Meaning and Necessity Carnap explicitly affirms that intensions are not names either of concepts or of abs­tract entities.  He maintains that like physical properties intensions may be said to be objective without invoking any hypostatization, and that they are indifferent to either concrete or abstract objects.  Carnap's intensions are remi­niscent of the Scholastic logicians' distinction between suppositio and significatio for terms, although Carnap never makes this comparison.  According to the theory of supposi­tio a univocal term's significatio or meaning is the same whether the term occurs either as a subject or as a predi­cate in an affirmative categorical proposition.  But its suppositio or supposition as a subject is called "personal", because it references the individual members of the class according to its associated quantifier, while its supposition as a predicate is called "simple", because no reference is made to the members of the class it signifies, and its meaning is used indifferently with respect to instantiation. It is the use of simple supposition that enables both the Aristotelian-Scholastic logician and the ordinary-language user to say, “Every raven is black” and affirm the reality of the attribute blackness without also affirming the existence of a Platonic entity called “blackness.”  The Aristotelian logician can distinguish names and predicates while still affirming that the descriptive predicates describe something real.  This capability is denied the user of the Russellian predicate logic, who can only affirm the reality of blackness by quantifying the predicate and therefore treat it as an entity; he can only distinguish names and predicates by being nominalist, by denying that descriptive predicates describe anything.  As it happens, when Quine attacks Carnap's admission of attributes and intensions, as he does in "On the Individuation of Attri­butes" (1975) in Theories and Things, he attacks Carnap's use of analytic statements and does not claim that Carnap has confused names and predicates.  But even apart from the issue of analyticity, Carnap's theory of intensions is inconsistent, because he also accepts the Russellian predicate logic.  In the section of Meaning and Necessity in which he discusses variables, Carnap explicitly agrees with Quine's view that the ontology to which one's use of langu­age commits oneself comprises simply of the objects that one treats as falling within the range of values of one's variables, and he explicitly accepts Quine's refrain that to be is to be the value of a variable.  Quine and Whitehead recognized, as Carnap had not, that one's logic shapes one's metaphysics, and Quine's papers on theory of reference had as their basis the thesis that the Russellian logic expres­ses existence exclusively by means of the instantiating quantifiers.
          The Russellian manner of expressing ontological commitment has its peculiar and controversial aspects, which are clear when contrasted with the earlier Aristotelian logic.  In the Aristotelian logic the quantifier does not affirm existence.  Instead existence is affirmed by the copula term "is", as in "Every raven is black.”  The noteworthy difference is that in the Russellian notational conventions the only existence that can be affirmed is the entities referenced by the quantified variable, such that any attempt to affirm the reality of attributes or proper­ties must describe them as entities referred to by a quanti­fied predicate.  In the Aristotelian logic, however, the reality of what may be called an attribute signified by the predicate need not be hypostatized as some kind of Platonic entity.  Quine is therefore consistent in his use of the Russellian logic, when he describes the reality status of red, the property, as an abstract “entity”, and when he describes the reality status of red, the meaning, as a mental “entity.”  According to the syntactical categories admitted by the Russellian logic all philosophers are either nominalists or Platonists, since they must either deny attributes as real by not quantifying the predicate, or they must affirm them as Platonic entities by quantifying over the predicate.  In the Russellian logic attributes, properties, aspects, and accidents have no reality status except as subsis­ting entities.  Carnap's attempt to admit intensions or meanings and properties that are not hypostatized, is inconsistent with his use of the Russellian logic and with his agreement with Quine that ontology is described by means of bound variables.  And his complaint about erroneously label­ing philosophers "Platonists" is similarly inconsistent.  Other and more consistent philosophers have recognized the Russellian logistic to be an Orwellian-like "newspeak" for advocating a nominalist agenda hidden in its notational conventions, which the pontificating Quine would enforce as a "canonical notation."
          In his Medieval Logic and Metaphysics (1972) the Uni­versity of Manchester British philosopher, David P. Henry, asks how modern logic, caught as it is in the "entanglement" of the expression of existence in the quantifiers, can recapture the untrammeled approach to existence enjoyed by its medieval predecessors.  He proposes reconsideration of the modern formal logic of the Polish logician S. Lesniewski (1886-1939), which is unfamiliar to most modern logicians.  In his autobiography Quine recounts his arguing with Lesniewski about "abstract entities" (Quine's characterization) while visiting Warsaw in the 1930's.  Henry notes that Lesniewski's logic employs an interpretation of the quanti­fiers, which enables their dissociation from its currently conventional entanglement with the notion of existence.  Henry gives examples of how Lesniewski's interpreted system with its ontology may be used in the analysis of medieval themes including suppositio with an artificial language designed by Henry.  In the present context the significance of Henry's work is that it shows how Quine's ontological agenda does not imply a simplistic dichotomy between modern mathematically expressed logic and antiquated colloquially expressed Aristotelian logic, but rather depends on very specific notational conventions distinctive of the Russel­lian logistic, to which there can and do exist alternatives.  Quine's weltanschauung seen through the lenses of Russellian logistic with its ontological agenda reducing attributes either to "abstract entities" or to unreality is terminal case of the mathematician’s disease, and it invites com­parison with the obliviously contemplative noblemen of the airborne floating island of Laputa in Swift's satirical Gulliver's Travels.  The Laputians viewed the world through the lenses of Cartesian geometry with Descartes' ontology of primary and secondary qualities.  In Descartes' philosophy only geometrical or "primary" qualities have objective real­ity, while all others are "secondary" in the sense of subjective and unreal.  The Laputian noblemen were so obliviously faithful to their distorted Cartesian view of the real world, that they viewed all reality as geometrical figures including even their wives, who were not similarly faithful to the Cartes­ian ontology, and who therefore felt so neglected that they were inclined to be unfaithful to their husbands.  Comparison with Gulliver's travelogue is not merely rhetorical.  Quine's rejection of proper­ties, attributes and qualities denies such qualita­tive differentiation its foundation in reality, and renders Quineian reality as starkly nominalist as Descartes' was extensionalist.  And it may be added that attempted paraphrasis by quantifying predicates does not evade nominalist ontology; it only incurs a fallacy that Whitehead called “misplaced concreteness, the Platonic hypostatization of properties which earlier logicians had avoided by their theory of suppositio.  Also the nominalism built into the Russellian notational conventions by combining existence and quantification is a prior ontological commitment, which is as inconsistent with Quine's ontological relativity as his Positivist behaviorism. Like the Laputian nobility, professors of Russellian predicate logic would greatly benefit, if their graduate-student assistants, who must humor the professor’s pretenses, were what Gulliver called “flappers”, i.e. assistants who swat their superiors in the face whenever the superiors lost touch with reality.