It is commonly accepted, after Frege, that identity statements like “Tully is Cicero” differ from statements like “Tully is Tully”. For the former, unlike the latter, are informative. One way to deal with the information problem is to postulate that the terms ‘Tully’ and ‘Cicero’ come equipped with different informative values. Another approach is to claim that statements like these are of the subject/predicate form. As such, they should be analyzed along the way we treat “Tully walks”. Since proper (...) names can appear in predicative position we could go as far as to dismiss the sign of identity altogether, some told us. I will try to discuss the advantages and/or disadvantages of this approach and investigate whether Frege’s view that the ‘is’ of identity must be distinguished from the ‘is’ of predication can be reconciled with the fact that names can appear in predicative position. (shrink)

KANT ARGUES AT GREAT LENGTH in the Critique of Pure Reason that the existence of God cannot be demonstrated by means of theoretical reason. For after dividing all traditional theistic proofs into three different kinds—the ontological, the cosmological, and the physico-theological—Kant argues first that the cosmological and physico-theological implicitly assume the ontological argument and then that the ontological argument is necessarily fallacious. By restricting knowledge in this manner Kant notoriously makes room for faith, that is, in this case, for a (...) practical proof of the existence of God, which he develops in the Critique of Practical Reason. Kant’s reasons for rejecting theoretical proofs of the existence of God have received considerable attention. In particular, Kant’s objection to the ontological argument, namely that existence is not a real predicate, still seems relevant in contemporary philosophy of religion. What has not received much attention, however, is the relationship between Kant’s rejection of theistic proofs in his critical period and his views on the matter in his pre-critical period. For throughout his pre-critical period, but especially in his The Only Possible Argument in Support of a Demonstration of the Existence of God, Kant believes that there is a theoretical proof of the existence of God. One would naturally expect Kant’s criticisms of theistic proofs as developed in the “ideal of pure reason” to apply in straightforward ways to his earlier attempts at a theistic proof. However, Kant rejects the three traditional arguments in The Only Possible Argument just as he does in the first Critique. Further, his reason for rejecting the ontological argument in particular is identical to the one presented in the first Critique: “Existence is not a predicate or a determination of a thing.” Accordingly, Kant understood himself to be developing a theistic proof in The Only Possible Argument that is distinct from the three traditional arguments and is also not subject to the objections he raises against them. Given that Kant rejects all theoretical proofs of God’s existence in his critical period and given that he did not take his critical objections to the traditional proofs to apply to the theistic proof developed in The Only Possible Argument, what is his justification for rejecting his pre-critical argument for God’s existence? (shrink)

Two different definitions of numerical identity occur in Aristotle's works, namely: (i) "A" and "B" are both names of one thing; (ii) A and B constitute unity. These definitions can be traced back respectively to the following theories of predication: (i)' the sentences whose subjects are accidents are actually ill-formed; (ii)' in some cases the accidents are not eliminable subjects. Since (i)' and (ii)' are irreparably inconsistent, the theory of identity is inconsistent too; in this paper are (...) explored the consequences of such an inconsistence, mainly as far as the fallacies depending both on combination and division and on accident are concerned. (shrink)

One of the many important tasks of semantics is to provide an account of the substitution patterns of a language—that is, to furnish an explanation of the conditions under which semantic values of complexes are preserved when components are replaced. The importance of this issue is plain: we only have to recall the debates regarding substitutivity between proponents of direct reference theories and advocates of some version of Fregeanism, as well as the disagreements among different proponents of direct reference theories (...) as regards substitutivity in belief reports. This is why it is important to articulate an acceptable principle of substitution. A traditional statement of the principle of substitution holds that codesignative singular terms should be intersubtitutable salva veritate. In the past I have argued that such a principle is not connected properly to some pretheoretical data about the function of referring terms. In this chapter I argue that such a principle does not gain support either from other, more fundamental, laws. I end by defending the adequacy of a different principle of substitution. (shrink)

Identity, existence, predication, necessity, and truth are fundamental philosophical concerns. Colin McGinn treats them both philosophically and logically, aiming for maximum clarity and minimum pointless formalism. He contends that there are real logical properties that challenge naturalistic metaphysical outlooks. These concepts are not definable, though we can say a good deal about how they work. The aim of Logical Properties is to bring philosophy back to philosophical logic.

Are there nonexistent things? What is the nature of informative identity statements? Are the notions of essential property and of essence intelligible, and, if so, how are they to be understood? Are individual things material substances or clusters of qualities? Can the account of the unity of a complex entity avoid vicious infinite regresses? These questions have attracted widespread attention among philosophers recently, as evidenced by a proliferation of articles in the leading philosophical journals. In Being Qua Being they (...) receive systematic, unified treatment, grounded in an account of the nature of the application to the world of our conceptual apparatus. A central thesis of the book is that the topic of identity is primary, and that existence and predication, both essential and accidental, are to be understood in terms of identity. (shrink)

'There is much food for thought in McGinn's discussions and each chapter is rich with a series of considerations for thinking that the currently received views on the various topics have some serious difficulties that need confronting... For those interested in metaphysics and the philosophy of logic, this book will stimulate much further thought' -Mind 'The sweep of the book is broad and the pace is brisk... There is much material here to provide the basis for many a deep philosophical (...) discussion' -Mind 'Lucid and provocative little book... clear, direct and well argued' -Times Higher Education SupplementIdentity, existence, predication, necessity, and truth are fundamental philosophical concerns. Colin McGinn treats them both philosophically and logically, aiming for maximum clarity and minimum pointless formalism. He contends that there are real logical properties that challenge naturalistic metaphysical outlooks. These concepts are not definable, though we can say a good deal about how they work. The aim of Logical Properties is to bring philosophy back to philosophical logic. (shrink)

Identity, existence, predication, necessity, and truth are fundamental philosophical concerns. Colin McGinn treats them both philosophically and logically, aiming for maximum clarity and minimum pointless formalism. He contends that there are real logical properties that challenge naturalistic metaphysical outlooks. These concepts are not definable, though we can say a good deal about how they work. The aim of Logical Properties is to bring philosophy back to philosophical logic.

The aim of this short book is to discuss the traditional topics of philosophical logic without the “formalistic fetishism and scholasticism” that McGinn associates with recent work in the field. The writing is indeed crisp, engaging, and free of formalisms. The book consists of five separate essays—one each on identity, existence, predication, necessity, and truth—loosely united by the general theme that these “logical properties” are real and irreducible. “These concepts,” McGinn says, “form a conceptual bedrock; they stand, as (...) it were, underneath all our other concepts. They have no analysis”. (shrink)

Are there nonexistent things? What is the nature of informative identity statements? Are the notions of essential property and of essence intelligible, and, if so, how are they to be understood? Are individual things material substances or clusters of qualities? Can the account of the unity of a complex entity avoid vicious infinite regresses? These questions have attracted widespread attention among philosophers recently, as evidenced by a proliferation of articles in the leading philosophical journals. In Being Qua Being they (...) receive systematic, unified treatment, grounded in an account of the nature of the application to the world of our conceptual apparatus. A central thesis of the book is that the topic of identity is primary, and that existence and predication, both essential and accidental, are to be understood in terms of identity. (shrink)

The standard approach to the so-called paradoxes of identity has been to argue that these paradoxes do not essentially concern the notion of identity but rather betray misconceptions on our part regarding other metaphysical notions, like that of an object or a property. This paper proposes a different approach by pointing to an ambiguity in the identity predicate and arguing that the concept of identity that figures in many ordinary identity claims, including those that appear (...) in the paradoxes, is not the traditional philosophical concept but one that can be defined in terms of relevant similarity. This approach to the paradoxes will be argued to be superior to the standard one. (shrink)

Many fourteenth-century logicians took affirmative propositions to maintain that the subject term and the predicate term stand or supposit for the same. This is called the identity theory of predication by historians and praedicatio identica by Paul of Venice and others. The identity theory of predication was an important part of early fourteenth-century Trinitarian discussions as well, but what was called praedicatio identica by Duns Scotus and his followers in this context was something different. After some (...) remarks on Scotus’s view and its background, I shall analyse Adam Wodeham’s explanation of Scotus’s praedicatio identica and how he understood the assumptions pertaining to supposition in the Scotist approach. I also describe Wodeham’s own solution to Trinitarian sophisms, which did not deviate from the identity theory of predication. (shrink)

Peter Geach famously holds that there is no such thing as absolute identity. There are rather, as Geach sees it, a variety of relative identity relations, each essentially connected with a particular monadic predicate. Though we can strictly and meaningfully say that an individual a is the same man as the individual b, or that a is the same statue as b, we cannot, on this view, strictly and meaningfully say that the individual a simply is b. It (...) is difficult to find anything like a persuasive argument for this doctrine in Geach's work. But one claim made by Geach is that his account of identity is the account most naturally aligned with Frege's widely admired treatment of cardinality. And though this claim of an affinity between Frege's and Geach's doctrines has been challenged, the challenge has been resisted. William Alston and Jonathan Bennett, indeed, go further than Geach to argue that Frege's doctrine implies Geach's. If Alston and Bennett are right, then those who favor a broadly Fregean treatment of cardinality have no choice but to adopt Geach's doctrine of relative identity. And because contemporary set-theoretic accounts of cardinality are essentially Fregean in all respects relevant to this issue (see §11 below), it follows from Alston and Bennett's claim that virtually every standard modern treatment of cardinality requires a 'relativized' treatment of identity. The purpose of this paper is to argue against the implication claimed by Alston and Bennett. Despite some superficial similarities between Frege's treatment of cardinality and Geach's treatment of identity, the two doctrines are fundamentally opposed. Frege's account of cardinality, and its set-theoretic descendants, are all inconsistent with the claim that identity is 'relative' in Geach's sense. (shrink)

Stephen Read presented harmonious inference rules for identity in classical predicate logic. I demonstrate here how this approach can be generalised to a setting where predicate logic has been extended with epistemic modals. In such a setting, identity has two uses. A rigid one, where the identity of two referents is preserved under epistemic possibility, and a non-rigid one where two identical referents may differ under epistemic modality. I give rules for both uses. Formally, I extend Quantified (...) Epistemic Multilateral Logic with two identity signs. I argue that a uniform meaning for identity tout court can be given by adopting Maria Aloni’s account of reference using conceptual covers. We obtain a harmonious set of rules for identity that is sound and complete for Aloni’s model theory. (shrink)

'identity' includes a family of relations and is wrongly restricted to what satisfies leibniz's law: diachronic and strict identity are related since the criteria of the former are just the criteria of continuity of stages of the strictly identical continuant. A general account can be given in terms of the preservation of a weighted preponderance of properties of the stages. Puzzle cases arise because of contextual shifts in the weightings assigned; in the case of persons this is particularly (...) clear because of change of emphasis between mental and physical, Both of which classes of predicate are applicable. (shrink)

Standard sorites paradoxes can always be put into a simple canonical form, employing the sole inference modus ponens. For example, consider the following paradox. Take a continuum of colours going from red to blue, and let a1,..., am be a sequence of segments of this continuum such that each segment is phenomenologically indistinguishable in colour from its immediate neighbours. Let Fx be the predicate ‘x is red’. Then the untrue conclusion Fam can be inferred from the premises Fa0 and Fan (...) → Fan + 1. (shrink)

How is it possible that a thing singled out not exist? How is it possible that two things singled out be numerically identical? How is one to understand the relationship between, say, a quality of a thing and what this quality is? And how is one to understand the relation between this quality and the thing which happens to be thus qualified? Trying to answer these four questions involves investigation of the four senses of the verb "to be," or of (...) the concepts of existence, identity, essential and accidental predication. Butchvarov’s thesis is that these four questions admit of a common answer, that the cornerstone of this comprehensive theory is an answer to the second question, and that this crucial answer depends on making some such distinction as his between "objects" and "entities." The bare bones of his argument are these: We commonly make statements of the form "a is b" where "a" and "b" are used referringly. A "material identity" statement of this form may be true. If true, it is about one thing; yet what it is about appears to be distinct things. This distinctness is not a real distinction among existents, nor does it arise solely or primarily from features of language. Butchvarov’s account is based on a distinction "of reason" between objects and entities. An entity is an existent, a constituent of the world. An object is whatever can be singled out once, and only once, in perception or imagination or in "thought". Entities as such cannot be singled out, yet they may be recognized through applications of a conceptual apparatus to objects. A material identity statement, then, states that two objects are one entity. If true, it is both about two distinct objects and about the one entity which each is. When two objects are judged to be one entity, then indiscernibility is enforced. Seeming counterexamples to the indiscernibility of identicals are explained in terms of the distinction between objects and entities. Though some applications of the concept of identity are relative to sortal characteristics, others are not. The latter are prior to the former. These primary judgments constitute the backbone of "thought" and discourse. They are governed by impersonal, nonhuman "paradigms." There are entities, of course; and there are objects, though as objects none exists. Some objects are entities, some are not. The notion of existence, like the notion of identity in its material role, is then a principle of classification, a concept. Butchvarov examines nine objections to this claim, and elaborates his distinction between objects and entities. He concludes that identifiability, hence indefinite reidentifiability, is the logically sufficient condition of applicability of the concept of existence. A statement such as "Socrates is white" is a disguised conjunction, viz., "Socrates has this color, and this color is white." The second conjunct is an "essential" statement; it says of an object singled out that it is a certain entity; or, to allow for essences of nonexistent objects, it states what entity the object would be were it an entity. An essential statement is not a material identity statement, for only one of its terms is used referringly. The essence of an object is not a property of it, for it is what the object is or would be. Whereas logically prior consciousness of objects is intentional and non-conceptual, consciousness of entities is conceptual and nonintentional; it consists in recognizing that a thing can be identified by oneself or by others. What is accidentally white, say, cannot be a material substance or bare particular; therefore it is a "cluster" of qualities. The Resemblance Theory, according to which qualities are particulars, is not a coherent alternative to the Identity Theory; therefore the qualities an individual happens to have are themselves universals. The Bradleyan critique of ontological atomism is cogent; therefore an individual is a cluster of qualities each of which depends for its "formal identity" on its being together with the rest. An individual’s having qualities is then to be understood in terms of the necessary togetherness of the qualities constitutive of it. Since in addition each of these qualities is essentially a universal, and specific universals are contingently coinstantiated, the predication in question is properly regarded as accidental. The problem of identifying quality-clusters through space and time is discussed. (shrink)

Each of the topics mentioned in the title has its own chapter. The unifying theme is McGinn’s conception of naive common sense views of identity, existence, predication, necessity, and truth, which are argued for as being correct. McGinn thinks they should replace entrenched rival treatments of these subjects. However, some of the views McGinn takes as naive seem far from naive or in common use to this reader. This is a technical work in philosophical logic, not in the (...) sense that it is strewn with technical symbols of formal logic. It takes up and discusses topics in a sophisticated way suitable for those working in the area and is not intended primarily for novices in the subject. Having said that, it is well written and clear so that there is much that would be rewarding to nonspecialists who wish to come to the subject. There is much in the way of close and interesting argumentation. (shrink)

SummaryA conception of numerical identity is introduced which, in accordance with a transcendental or imposition view of language, treats an identity predicate as having an ontologically generative function by genuinely being involved in the generation or construction of its domain of discourse. The proposed conception also allows for a plurality of identity predicates, each of which generating a domain, and it allows for the possibility that some such domains may not be unifiable with each other. All of (...) these informal notions are explicated in formal terms. Finally, a comparison to Scott and Fourman's intuitionistic conception of identity is made. (shrink)

SummaryA conception of numerical identity is introduced which, in accordance with a transcendental or imposition view of language, treats an identity predicate as having an ontologically generative function by genuinely being involved in the generation or construction of its domain of discourse. The proposed conception also allows for a plurality of identity predicates, each of which generating a domain, and it allows for the possibility that some such domains may not be unifiable with each other. All of (...) these informal notions are explicated in formal terms. Finally, a comparison to Scott and Fourman's intuitionistic conception of identity is made. (shrink)

I conclude that it is more accurate to say that, rather than trying to make logic metaphysical, Leibniz tries, in the context of a theistic system, to make metaphysics logical. ;I begin with a study of the principle of identity of indiscernibles, and show how it is best thought of as a principle which follows from a metaphysical interpretation of the principle of sufficient reason. It has been traditional to interpret the principle of identity of indiscernibles as primarily (...) a merely logical principle, and thus as either trivially true, if Leibniz succeeds in proving it, or else false or contingently true. I argue that it is instead necessarily true in a non-trivial or metaphysical sense, because the principles on which it is based are themselves of this metaphysical character, contrary to what is often assumed. ;In the second chapter, I show how God's activity and a metaphysical interpretation of the principle of sufficient reason underlie Leibniz's account of space and time. ;In the third chapter, I discuss the principle of sufficient reason in detail, showing that it actually consists of three separate principles: the principle of grounds, that every true proposition has a proof a priori; the principle of reason, that God does nothing without a sufficient reason; and the principle of causation, that every event has a cause. That each of these is considered a principle of sufficient reason is explained by Leibniz's equivocal use of the term 'reason.' I show that, of the various versions of the principle of sufficient reason, only the principle of reasons provides an adequate foundation for Leibniz's principle of identity of indiscernibles and theory of space and time. Furthermore, since chapters one and two show how the activity of God is presupposed by Leibniz's metaphysics, for Leibniz to derive his metaphysics from his logic, as some would have us suppose, he would have to provide a satisfactory a priori demonstration of God's existence. But this, I argue, he cannot do. Thus God's existence and rationality, rather than subject-predicate logic, are the foundations of Leibniz's metaphysics. ;It is commonplace, when writing about Leibniz, to give primacy to his logic over his metaphysics, and indeed to try to assimilate the latter to the former. In this essay, however, I give priority to Leibniz's metaphysical pronouncements, apart, as much as possible, from logical and linguistic considerations. (shrink)

The article outlines the main motivations for the Guise Theory and its intriguing theses concerning identity, predication, existence, and fiction. The second part of the article is devoted to an assessment of Castañeda’s theory. It discusses the most influential critiques of the Guise Theory, as well as Russell’s objection to theories of nonexistent objects. The last section of the article contains a comparison of the Guise Theory with the Meinong’s Theory of Objects, and points out that despite various (...) similarities, we should draw a distinction between original and moderate versions of Meinong’s theory. The main motivation for this distinction are differences between accounts of predications, which allow us to call the Guise Theory “quasi-Meinongian” rather than just “Meinongian”. This is because one of its main claims is taken from the work of Meinong’s pupil Ernst Mally, and not from Meinong himself. (shrink)

In this paper we provide a framework for studying the ways in which food endures the passage of time. Central to our inquiry is the following Duration Question: when is it that the predicate-schema “Is an X-Food,” where “X-Food” stands for a certain type of food (e.g., Champagne, yoghurt) ceases to apply to an entity? We show that the answer depends on two independent theoretical aspects: the underlying conception of food and the kinds of change that a specific food can (...) undergo. We then argue that specific answers to the duration question should take the form of conceptual rethinking among different stakeholders (e.g., producers, consumers, institutions), where philosophers would feature among the experts guiding the negotiation. (shrink)

Wittgensteinian predicate logic (W-logic) is characterized by the requirement that the objects mentioned within the scope of a quantifier be excluded from the range of the associated bound variable. I present a sound and complete tableaux calculus for this logic and discuss issues of translatability between Wittgensteinian and standard predicate logic in languages with and without individual constants. A metalinguistic co-denotation predicate, akin to Frege’s triple bar of the Begriffsschrift, is introduced and used to bestow the full expressive power of (...) first-order logic with identity on W-logic in the presence of constants. (shrink)

Two connected themes have been at the core of the old perplexity regarding thinking and speaking about non-existent objects. One involves a question of reference. Can we refer to non-existent objects without, thereby, recognizing, in some sense, non-existent entities as objects of reference? The other involves a question about existence. Is existence a property representable by a predicate in a logically adequate symbohsm? It is argued (1) that existence is not to be construed as an attribute represented by a predicate, (...) (2) that nonnaming names introduce problems, not solutions to problems, (3) that purported properties such as self-identical are specious, and (4) that the Russell property is also seen to be specious by our consideration of predication. (shrink)

Two connected themes have been at the core of the old perplexity regarding thinking and speaking about non-existent objects. One involves a question of reference. Can we refer to non-existent objects without, thereby, recognizing, in some sense, non-existent entities as objects of reference? The other involves a question about existence. Is existence a property representable by a predicate in a logically adequate symbohsm? It is argued (1) that existence is not to be construed as an attribute represented by a predicate, (...) (2) that nonnaming names introduce problems, not solutions to problems, (3) that purported properties such as self-identical are specious, and (4) that the Russell property is also seen to be specious by our consideration of predication. (shrink)

Two connected themes have been at the core of the old perplexity regarding thinking and speaking about non-existent objects. One involves a question of reference. Can we refer to non-existent objects without, thereby, recognizing, in some sense, non-existent entities as objects of reference? The other involves a question about existence. Is existence a property representable by a predicate in a logically adequate symbohsm? It is argued (1) that existence is not to be construed as an attribute represented by a predicate, (...) (2) that nonnaming names introduce problems, not solutions to problems, (3) that purported properties such as self-identical are specious, and (4) that the Russell property is also seen to be specious by our consideration of predication. (shrink)

The article attempts to resolve the problem raised by richard sharvey's arguments supporting the thesis that temporal contexts present difficulties for quantification similar to those presented by alethic modal contexts. to this end a concept of temporally relativized identity for physical objects is introduced and explicated within a four-dimensional space-time view of the world. this in turn permits the introduction of the notion of "restricted" physical objects and the notion of "extended" physical objects. it is then shown how the (...) use of the introduced concepts together with careful attention to the details of temporal predication may permit the solution of the problem. (shrink)

It is a commonplace remark that the identity relation, even though not expressible in a first-order language without identity with classical set-theoretic semantics, can be defined in a language without identity, as soon as we admit second-order, set-theoretically interpreted quantifiers binding predicate variables that range over all subsets of the domain. However, there are fairly simple and intuitive higher-order languages with set-theoretic semantics in which the identity relation is not definable. The point is that the definability (...) of identity in higher-order languages not only depends on what variables range over, but also is sensitive to how predication is construed. This paper is a follow-up to , where it has been proven that no actual axiomatization of Leśniewski’s Ontology determines the standard semantics for the epsilon connective. (shrink)

The problems of referential opacity in psychological contexts require a solution, of which three types are indicated, that contains a profound theory of predication, identity, and individuation. a radical theory, not in the spirit of the current fashions, is outlined. it is called the guise-consubstantiation, conflation, and consociation theory. this theory was first expounded in "thinking and the structure of the world," "philosophia" (1974) and "critica" (1972). the present paper is an introduction to this essay, motivated by two (...) criticisms of romane clark in "not every object of thought has being," "nous" (1978). it is shown that clark's arguments rest on equivocations, one involving the data and the theory, and the other within the theory itself. thus, a discussion of philosophical method turns out to be crucial, and an analysis of expression 'true of' is offered. (shrink)

I am concerned with two theses of quine's which pertain to identity statements and names. My purpose is to prove that they are inconsistent, I.E., That not both can be true. The two theses are: (q1) (=a) can be treated as a simple predicate, And (q2) any statement of the form (a=a) is logically true.

We critically investigate and refine Dunn's relevant predication, his formalisation of the notion of a real property. We argue that Dunn's original dialectical moves presuppose some interpretation of relevant identity, though none is given. We then re-motivate the proposal in a broader context, considering the prospects for a classical formalisation of real properties, particularly of Geach's implicit distinction between real and ''Cambridge'' properties. After arguing against these prospects, we turn to relevance logic, re-motivating relevant predication with Geach's (...) distinction in mind. Finally we draw out some consequences of Dunn's proposal for the theory of identity in relevance logic. (shrink)