The foregoing set of theorems forms an effective foundation for the theory of situations and worlds. All twenty-five theorems seem to be basic, reasonable principles that structure the domains of properties, relations, states of affairs, situations, and worlds in true and philosophically interesting ways. They resolve 15 of the 19 choice points defined in Barwise (1989) (see Notes 22, 27, 31, 32, 35, 36, 39, 43, and 45). Moreover, important axioms and principles stipulated by situation theorists are derived (see Notes (...) 33, 37, and 38). This is convincing evidence that the foregoing constitutes a theory of situations. Note that worlds are just a special kind of situation, and that the basic theorems of world theory, which were derived in previous work, can still be derived in this situation-theoretic setting. So there seems to be no fundamental incompatibility between situations and worlds — they may peacably coexist in the foundations of metaphysics. The theory may therefore reconcile two research programs that appeared to be heading off in different directions. And we must remind the reader that the general metaphysical principles underlying our theory were not designed with the application to situation theory in mind. This suggests that the general theory and the underlying distinction have explanatory power, for they seem to relate and systematize apparently unrelated phenomena. (shrink)

In the debate about the nature and identity of possible worlds, philosophers have neglected the parallel questions about the nature and identity of moments of time. These are not questions about the structure of time in general, but rather about the internal structure of each individual time. Times and worlds share the following structural similarities: both are maximal with respect to propositions (at every world and time, either p or p is true, for every p); both are consistent; both are (...) closed (every modal consequence of a proposition true at a world is also true at that world, and every tense-theoretic consequence of a proposition true at a time is also true at that time); just as there is a unique actual world, there is a unique present moment; and just as a proposition is necessarily true iff true at all worlds, a proposition is eternally true iff true at all times. In this paper, I show that a simple extension of my theory of worlds yields a theory of times in which the above structural similarities between the two are consequences. (shrink)

The author engages a question raised about theories of nonexistent objects. The question concerns the way names of fictional characters, when analyzed as names which denote nonexistent objects, acquire their denotations. Since nonexistent objects cannot causally interact with existent objects, it is thought that we cannot appeal to a `dubbing' or a `baptism'. The question is, therefore, what is the starting point of the chain? The answer is that storytellings are to be thought of as extended baptisms, and the details (...) of this response receive attention in the paper. Once the storytelling is complete, and the characters have been baptized, a priori metaphysical principles linking the storytelling with the realm of nonexistent objects provide the referential, non-causal connection between the names used in the storytelling and the objects denoted by such names. [This is the original English version of an article that first appeared in German translation, translated into German by Arnold Günther and published in the Zeitschrift für Semiotik 9/1-2 (1987): 85-95. The version that appears here is, for the most part, unaltered.]. (shrink)

In this paper, we describe "metaphysical reductions", in which the well-defined terms and predicates of arbitrary mathematical theories are uniquely interpreted within an axiomatic, metaphysical theory of abstract objects. Once certain (constitutive) facts about a mathematical theory T have been added to the metaphysical theory of objects, theorems of the metaphysical theory yield both an analysis of the reference of the terms and predicates of T and an analysis of the truth of the sentences of T. The well-defined terms and (...) predicates of T are analyzed as denoting abstract objects and abstract relations, respectively, in the background metaphysics, and the sentences of T have a reading on which they are true. After the technical details are sketched, the paper concludes with some observations about the approach. One important observation concerns the fact that the proper axioms of the background theory abstract objects can be reformulated in a way that makes them sound more like logical axioms. Some philosophers have argued that we should accept (something like) them as being logical. (shrink)

In this paper, the author derives the Dedekind-Peano axioms for number theory from a consistent and general metaphysical theory of abstract objects. The derivation makes no appeal to primitive mathematical notions, implicit definitions, or a principle of infinity. The theorems proved constitute an important subset of the numbered propositions found in Frege's *Grundgesetze*. The proofs of the theorems reconstruct Frege's derivations, with the exception of the claim that every number has a successor, which is derived from a modal axiom that (...) (philosophical) logicians implicitly accept. In the final section of the paper, there is a brief philosophical discussion of how the present theory relates to the work of other philosophers attempting to reconstruct Frege's conception of numbers and logical objects. (shrink)

In this paper, I respond to D. Jacquette's paper, "Mally's Heresy and the Logic of Meinong's Object Theory" (History and Philosophy of Logic, 10 (1989): 1-14), in which it is claimed that Ernst Mally's distinction between two modes of predication, as it is employed in the theory of abstract objects, is reducible to, and analyzable in terms of, a single mode of predication plus the distinction between nuclear and extranuclear properties. The argument against Jacquette's claims consists of counterexamples to his (...) reductions and analyses. Reasons are offered for thinking that no such reduction/analysis of the kind Jacquette proposes could be successful. (shrink)

In this paper, the author shows how one can independently prove, within the theory of abstract objects, some of the most significant claims, hypotheses, and background assumptions found in Kripke's logical and philosophical work. Moreover, many of the semantic features of theory of abstract objects are consistent with Kripke's views — the successful representation, in the system, of the truth conditions and entailments of philosophically puzzling sentences of natural language validates certain Kripkean semantic claims about natural language.

Some recently-proposed counterexamples to the traditional definition of essential property do not require a separate logic of essence. Instead, the examples can be analysed in terms of the logic and theory of abstract objects. This theory distinguishes between abstract and ordinary objects, and provides a general analysis of the essential properties of both kinds of object. The claim ‘x has F necessarily’ becomes ambiguous in the case of abstract objects, and in the case of ordinary objects there are various ways (...) to make the definition of ‘F is essential to x’ more fine-grained. Consequently, the traditional definition of essential property for abstract objects in terms of modal notions is not correct, and for ordinary objects the relationship between essential properties and modality, once properly understood, addresses the counterexample. (shrink)

This paper serves as a kind of field guide to certain passages in the literature which bear upon the foundational theory of abstract objects. The foundational theory assimilates ideas from key philosophers in both the analytical and phenomenological traditions. I explain how my foundational theory of objects serves as a common ground where analytic and phenomenological concerns meet. I try to establish how the theory offers a logic that systematizes a well-known phenomenological kind of entity, and I try to show (...) the various ways the theory systematizes the ideas of many analytic philosophers. The ideas of Plato, Leibniz, Frege, Russell, Goedel and even Kripke become connected through those of Brentano, Meinong, Husserl, and Mally. -/- The field guide will not only document the passages in which the distinction between two kinds of predication originates, but also document the other surprising, and often unrelated, contexts where the distinction reappears in the work of others. It will also document ways in which the theory can be used to represent precisely the ideas of the philosophers mentioned above. The resulting guide will bring together the works of many different authors, including some clearly within the analytic tradition, some clearly within the phenomenological tradition, and some who straddle the divide. (shrink)

The author examines the differences between the general intensional logic defined in his recent book and Montague's intensional logic. Whereas Montague assigned extensions and intensions to expressions (and employed set theory to construct these values as certain sets), the author assigns denotations to terms and relies upon an axiomatic theory of intensional entities that covers properties, relations, propositions, worlds, and other abstract objects. It is then shown that the puzzles for Montague's analyses of modality and descriptions, propositional attitudes, and directedness (...) towards nonexistents can be solved using the author's logic. (shrink)

The subject matter of this work covers the issues or problems listed below: * The problem of the ontological status of language signs and a more general philosophical problem connected with it: * What is language as a system of signs, which – on the one hand – serves to: 1) represent our knowledge about the reality which is being recognized, and, on the other one to: 2) a. explore and better cognize or discover it, b. describe it in an (...) adequate manner, and c. enable users to make interpersonal communication? All the pragmatic functions of language require carrying out its logical-philosophical analysis, and this means both regarding its syntax and semantics. Such an analysis is not possible without determining the following: How are signs perceived and what is their ontological nature in the so-called functional approach towards logical semiotics of natural language, founded on two ways of their usage: either as signs which we use in concrete situational or situational-language contexts or as isolated signs detached from such contexts? In the first case, they are language tokens (concretes), existing material objects perceived through the senses, with a fixed temporal-spatial location, in the other one – they are non-concretes and as such (as the majority of researchers in the field of philosophy and linguistics accept) – abstract objects, language types. The type-token distinction (differentiation between abstract and concrete) has already acquired a certain status in contemporary philosophy and is of considerable importance to metaphysics and epistemology in particular. Indeed, it is most often illustrated with reference to language signs (words, expressions) as the distinction type/token of a sign, introduced into semiotics by Ch. S. Peirce. In the semiotic analysis, and also in the linguistic one, there are used both types and tokens of signs, however, often without paying due attention to when it is said about types and when about tokens. This is related to the problems which are still considered by the philosophy of language: What is the type? What is the token (specimen)? What are the mutual relations between the type and the token? Disputes concerning providing answers to these questions are related to existential issues dealing with the ontological status of these language signs and two currents within the ontology of language, remaining under the influence of two fundamental concepts formed in the debate: nominalism and realism. The author presents in brief different stances on the above-mentioned issues or problems, as well as argues that from the logical point of view: 1) working out any theoretical conception of language must take into account its bi-aspectual characteristics: as a language of expression-tokens and as a language of expression-types; 2) advocating either of the standpoints: (a) types exist independent of their tokens, or (b) it is not so, can be omitted in syntactic considerations on language; 3) mutual relations between sign-tokens differ from the mutual relations between sign-types, yet; 4) determination of the mutual relation between sign-types and sign-tokens depends on accepting either of the standpoints: (a) or (b); 5) semantic or semantic-pragmatic concepts of language, such as meaning, denotation, interpretation should be defined exclusively for types of tokens, but their definitions require certain reference to the functions which sign-tokens perform in the language (words, expressions), or to relations between them; 6) The concept of an act of language communication differs from general language communication: the first one is defined by means of sign-tokens, whereas the other one – with the use of sign-types. (shrink)

Our research concerns a formal representation of Bolzano’s original concepts of Substanz and Adhärenz. The formalized intensional theory enables to articulate a question about the consistency of a part of Bolzano’s metaphysics and to suggest an answer to it in terms of contemporary model theory. The formalism is built as an extension of Zalta’s theory of abstract objects, describing two types of predication, viz. attribution and representation. Bolzano was aware about this distinction. We focus on the consistency of this formalism (...) and the description of its semantics. Firstly, we explore the possibility to reconstruct a Russellian antinomy based on the concept of the Bolzano’s Inbegriff of all adherences. Our aim is to show limitations of his theory that prevent a contradiction when the Inbegriff consists of non-self-referential adherences. Next, we discuss two competing semantics for the proposed theory: Scott’s and Aczel’s semantics. The first one yields a problematic result, that there are no models for the considered theory, containing a non-empty collection of all adherences. This is due to the fact that Scott’s structures verify the formula on reloading abstracts in extensional contexts. We show that Aczel’s semantics does not contain this difficulty. There are described Aczel’s models with a non-empty set of all adherences. The self-referentiality of such a collection becomes irrelevant here. Finally, we show that there are Aczel’s structures verifying the formula on reloading abstracts and we exclude them from the class of models intended for our theory. (shrink)

The topic of our analysis is the argument for the existence of substances given by Bernard Bolzano in Athanasia, where he essentially employs two ontological categories: substance and adherence. Bolzano considers the real and conditioned Inbegriff of all adherences, which are wirklich and nicht selbst bestehen. He claims that the formed collection is dependent on something external and non-adherential, which therefore is a substance. Bolzano’s argumentation turns out to be structurally similar to his argument for the existence of God from (...) Lehrbuch der Religionswissenschaft, but in each of these reasonings, we find different plausible interpretations of the key concept “Inbegriff”. The latter argumentation refers to the mereological totality of existentially conditioned objects. We propose the explication of the Bolzanian Inbegriff of all adherences using two types of predication: we consider its extension as composed of certain intensional counterparts of adherences. In our approach, we use a fragment of the theory of abstract objects formulated by E. Zalta, describing two different relations between individuals and properties: extensional exemplification and intensional encoding. We put our reconstruction in a wider context of Bolzano’s ontology, formulating the needed axioms with two primitive predicates of second order... is an adherence,... is conditioned by something real as well as the conditionally introduced first order predicate constant \ for Inbegriff of all adherential ideas. Finally, we sketch a model for our theory. (shrink)

Bare particularism is a constituent ontology according to which substances—concrete, particular objects like people, tables, and tomatoes—are complex entities constituted by their properties and their bare particulars. Yet, aside from this description, much about bare particularism is fundamentally unclear. In this paper, I attempt to clarify this muddle by elucidating the key metaphysical commitments underpinning any plausible formulation of the position. So the aim here is primarily catechismal rather than evangelical—I don’t intend to convert anyone to bare particularism, but, by (...) looking at a series of questions, to instead specify what, if one is a bare particularist, one is committed to. Along the way, I address three major objections: a classic objection about whether bare particulars have properties, a new objection raised by Bailey, and an understanding objection that questions some of the position’s resources. (shrink)

The ideas of fixed points (Kripke in Recent essays on truth and the liar paradox. Clarendon Press, London, pp 53–81, 1975; Martin and Woodruff in Recent essays on truth and the liar paradox. Clarendon Press, London, pp 47–51, 1984) and revision sequences (Gupta and Belnap in The revision theory of truth. MIT, London, 1993; Gupta in The Blackwell guide to philosophical logic. Blackwell, London, pp 90–114, 2001) have been exploited to provide solutions to the semantic paradox and have achieved admirable (...) success. This happy situation naturally encourages one to look for other philosophical areas of their further applications where paradoxical results seem to follow from intuitively acceptable principles. In this paper, I propose to extend the use of these ideas to give two new treatments of abstract objects. Sections 1 and 2 below check several abstractionist theories and their main defects. Section 3 shows how the two ideas can be applied to generate consistent theories of abstract objects without any ad hoc restriction on any principle. (shrink)

According to Crane’s schematicity thesis (ST) about intentional objects, intentionalia have no particular metaphysical nature qua thought-of entities; moreover, the real metaphysical nature of intentionalia is various, insofar as it is settled independently of the fact that intentionalia are targets of one’s thought. As I will point out, ST has the ontological consequence that the intentionalia that really belong to the general inventory of what there is, the overall domain, are those that fall under a good metaphysical kind, i.e., a (...) kind such that its members figure (for independent reasons) in such an inventory. Negatively put, if there are no things of a certain metaphysical kind, thoughts about things of that kind are not really committed to such things. Pace Crane, however, this does not mean that the intentionalia that are really there are only those that exist. For existence, qua first-order property, is no metaphysical kind. Thus, there may really be intentionalia that do not exist, provided that they belong to good metaphysical kinds. (shrink)

The specification and implementation of computational artefacts occurs throughout the discipline of computer science. Consequently, unpacking its nature should constitute one of the core areas of the philosophy of computer science. This paper presents a conceptual analysis of the central role of specification in the discipline.

This paper considers two issues raised by the claim that fictional characters are abstract artifacts. First, given that artifacts normally have functions, what is the function of a fictional character? Second, given that, in experiencing works of fictions, we usually treat fictional characters as concrete individuals, how can such a phenomenology fit with an ontology according to which fictional characters are abstract artifacts? I will indirectly address the second issue by directly addressing the first one. For this purpose, I will (...) rely on the notion of a mental file. I will argue that the function of fictional characters is the generation of mental files of a special kind. I will show that our experience of fictional characters as concrete individuals depends on the kind of mental files that are generated by fictional characters as abstract artifacts. I will conclude that an appreciator of a work of fiction can open two files about a certain fictional character; one about the character as an individual in the fictional world, and the other about the character as an abstract artifact in the actual world. In this sense, our relation to a fictional character is characterized by a duality of files or ‘twofileness’. (shrink)

It is argued that a number of important, and seemingly disparate, types of representation are species of a single relation, here called structural representation, that can be described in detail and studied in a way that is of considerable philosophical interest. A structural representation depends on the existence of a common structure between a representation and that which it represents, and it is important because it allows us to reason directly about the representation in order to draw conclusions about the (...) phenomenon that it depicts. The present goal is to give a general and precise account of structural representation, then to use that account to illuminate several problems of current philosophical interest — including some that do not initially seem to involve representation at all. In particular, it is argued that ontological reductions (like that of the natural numbers to sets), compositional accounts of semantics, several important sorts of mental representation, and (perhaps) possible worlds semantics for intensional logics are all species of structural representation and are fruitfully studied in the framework developed here. (shrink)

In this paper I present a formal language in which complex predicates stand for properties and relations, and assignments of denotations to complex predicates and assignments of extensions to the properties and relations they denote are both homomorphisms. This system affords a fresh perspective on several important philosophical topics, highlighting the algebraic features of properties and clarifying the sense in which properties can be represented by their extensions. It also suggests a natural modification of current logics of properties, one in (...) which some complex predicates stand for properties while others do not. (shrink)

According to the so-called ‘artifactual theory’ of fiction, fictional objects are to be considered as abstract artifacts. Within this framework, fictional objects are defined on the basis of their complex dependence on literary works, authors, and readership. This theory is explicitly distinguished from other approaches to fictions, notably from the imaginary-object theory. In this article, I argue that the two approaches are not mutually exclusive but can and should be integrated. In particular, the ontology of fiction can be fruitfully supplemented (...) by a phenomenological analysis, which allows us to clarify the defining modes of givenness of fictional objects. Likewise, based on the results of the artifactual theory, some assumptions in the imaginary-object theory, which are liable to be interpreted as laying the ground to phenomenalism, can be corrected. (shrink)

Since 2002 we have been testing and refining a methodology for ontology development that is now being used by multiple groups of researchers in different life science domains. Gary Merrill, in a recent paper in this journal, describes some of the reasons why this methodology has been found attractive by researchers in the biological and biomedical sciences. At the same time he assails the methodology on philosophical grounds, focusing specifically on our recommendation that ontologies developed for scientific purposes should be (...) constructed in such a way that their terms are seen as referring to what we call universals or types in reality. As we show, Merrill’s critique is of little relevance to the success of our realist project, since it not only reveals no actual errors in our work but also criticizes views on universals that we do not in fact hold. However, it nonetheless provides us with a valuable opportunity to clarify the realist methodology, and to show how some of its principles are being applied, especially within the framework of the OBO (Open Biomedical Ontologies) Foundry initiative. (shrink)

In this paper, I explore a seldom-recognized connection between the ontology of abstract objects and a current issue in the philosophy of chemistry. Specifically, I argue that realism with regard to universals implies a view of chemical elements similar to F.A. Paneth’s thesis about the dual nature of the concept of element.

This paper aims to introduce Meinongian Abstractionism (MA), i.e. a view on the metaphysics of truthmaking and modality. This approach is based on the notion of objectives—one of the key elements of Alexius Meinong’s Theory of Objects. In the light of it, worlds are interpreted in terms of sets of subsistent and non-subsistent objectives. This—along with Meinong’s characterization of objectives—provides a ground for possible as well as impossible worlds. One of the consequences of Meinongain Abstractionism is a reformulation of the (...) relation of truthmaking in modal terms. Importantly, this reformulation avoids the problem of too-coarse grained analysis of truthmakers. This makes MA a metaphysically–oriented supporter of the so-called ‘hyperintensional revolution.’. (shrink)

The subject of my article is the principle of characterization – the most controversial principle of Meinong’s Theory of Objects. The aim of this text is twofold. First of all, I would like to show that Russell’s well-known objection to Meinong’s Theory of Objects can be reformulated against a new modal interpretation of Meinongianism that is presented mostly by Graham Priest. Secondly, I would like to propose a strategy which gives uncontroversial restriction to the principle of characterization and which allows (...) to avoid Russell’s argument. The strategy is based on the distinction between object- and metalanguage, and it applies to modal Meinongianism as well as to other so-called Meinongian theories. (shrink)

This paper is about intentional identity, the phenomenon of intentional attitudes having a common focus. I present an argument against an approach to explaining intentional identity, defended by Nathan Salmon, Terence Parsons and others, that involves positing exotic objects. For example, those who adopt this sort of view say that when two astronomers had beliefs about Vulcan, their attitudes had a common focus because there is an exotic object that both of their beliefs were about. I argue that countenancing these (...) exotic objects does not help us explain intentional identity. (shrink)

We want to say both that Sherlock Holmes does not exist, and that he is a fictional character. But how can we say these things without committing ourselves to the existence of Sherlock Holmes? Here I develop and defend a non-commital paraphrase of quantification over fictional characters, modeled on the non-commital paraphrase Kit Fine provides for quantification over possibilia. I also develop and defend the view that names for fictional characters are weakly non-referring, in Nathan Salmon’s sense, and so provide (...) us with a non-commital means to express singular propositions. The resulting position allows us to reap the benefits of Fictional Realism without paying the associated ontological cost. (shrink)

The authors consider a recurring objection to fictional realism, the view that fictional characters are objects. The authors call this the counting objection. Russell presses a version of the objection against Meinong’s view. Everett presses a version of the objection against contemporary fictional realist views, as do Nolan and Sandgren. As the authors see it, the objection assumes that the fictional realist must provide criteria of identity for fictional characters, so its force depends on the plausibility of that assumption. Rather (...) than coming up with such criteria, a fictional realist might argue that the demand is misplaced. (shrink)

A paradox about sets of properties is presented. The paradox, which invokes an impredicatively defined property, is formalized in a free third-order logic with lambda-abstraction, through a classically proof-theoretically valid deduction of a contradiction from a single premise to the effect that every property has a unit set. Something like a model is offered to establish that the premise is, although classically inconsistent, nevertheless consistent, so that the paradox discredits the logic employed. A resolution through the ramified theory of types (...) is considered. Finally, a general scheme that generates a family of analogous paradoxes and a generally applicable resolution are proposed. (shrink)

The triangle in general or the man as such are general objects. These are objects that possess the properties common to all the individual objects in their range. Stanisław Leśniewski and Tadeusz Kotarbiński, two Polish philosophers and logicians belonging to the Lvov-Warsaw School, produced several proofs aiming to show that such objects are impossible because the principles that govern them lead to a contradiction. In this paper I first clarify the structure of their proofs. Then I suggest a way to (...) elude their conclusion. In order to do that I use two Meinongian distinctions: the distinction between complete and incomplete objects, on the one hand, and the distinction between nuclear and extranuclear properties, on the other hand. I claim first that general objects are incomplete objects, i.e. they do not satisfy the ontological principle of the excluded middle, and second that the principle that governs the relations between the properties of general objects and the properties of the individual objects in their range should be restricted to nuclear properties. (shrink)

The aim of the paper is to defend the view according to which all simple fictional sentences are meaningless. If their assertions seem to convey some truth evaluable information, and fictional sentences themselves seem to be true or false, it is because some pragmatic mechanisms are operative, enabling the expression of propositions not encoded in the semantic content of these sentences. According to some theorists, the mechanisms responsible for that process are the same as those responsible for generating conversational implicatures. (...) I argue against that claim and maintain that to comprehend the information conveyed by a fictional assertion, one must determine what kind of fictional assertion it is and only then apply the relevant interpretative rule adjusted to the fictional sentence used in that act. (shrink)

This article presents an historical and conceptual overview on different approaches to logical abstraction. Two main trends concerning abstraction in the history of logic are highlighted, starting from the logical notions of concept and function. This analysis strictly relates to the philosophical discussion on the nature of abstract objects. I develop this issue further with respect to the procedure of abstraction involved by (typed) λ-systems, focusing on the crucial change about meaning and predicability. In particular, the analysis of the nature (...) of logical types in the context of Constructive Type Theory allows elucidation of the role of the previously introduced notions. Finally, the connection to the analysis of abstraction in computer science is drawn, and the methodological contribution provided by the notion of information is considered, showing its conceptual and technical relevance. Future research shall focus on the notion of information in distributed systems, analysing the paradigm of information hiding in dependent type theories. (shrink)

This paper is concerned with two concepts of qualitativeness that apply to intensional entities. I propose an account of pure qualitativeness that largely follows the traditional understanding established by Carnap, and try to shed light on its ontological presuppositions. On this account, an intensional entity is purely qualitative iff it does not ‘involve’ any particular. An alternative notion of qualitativeness—which I propose to refer to as a concept of strict qualitativeness—has recently been introduced by Chad Carmichael. However, Carmichael’s definition presupposes (...) a highly fine-grained conception of properties and relations. To eliminate this presupposition, I tentatively suggest a different definition that rests on a concept of perspicuous denotation. In the penultimate section, both concepts of qualitativeness are put to work in distinguishing between different ‘grades’ of qualitative discriminability. (shrink)

According to many realist philosophers of fiction, one needs to posit an ontology of existing fictional characters in order to give a correct account of discourse about fiction. The realists' claim is opposed by pretense theorists for whom discourse about fiction involves, as discourse in fiction, pretense. On that basis, pretense theorists claim that one does not need to embrace an ontology of fictional characters to give an account of discourse about fiction. The ontolog-ical dispute between realists and pretense theorists (...) is mainly a dispute in the realm of the phi-losophy of language concerning the status relative to pretense of discourse about fiction. Realists are persuaded that there is a sharp line between discourse in fiction and discourse about fiction while pretense theorists deny there exists such a line. I suggest that realists may have a wrong picture of discourse in fiction since, in many cases, discourse in fiction already contains many occurrences of discourse about fiction. Consequently, discourse about fiction, instead of ending fiction, should be regarded, following pretense theorists, as adding extra lay-ers of fiction. (shrink)

Oppenheimer & Zalta have re-formulated their non-modal version of the ontological argument, with the help of PROVER9, an automated reasoning engine. The authors end up rejecting the new argument; however, the theist has a rejoinder worth considering. But after presenting the rejoinder, I highlight that the conceivability of the being does not imply its possibility. One lesson is that even non-modal ontological arguments must engage modal matters concerning God. Another lesson is that if PROVER9 is able to derive a conclusion (...) from fewer premises, the proof is sometimes inferior as an argument. (shrink)

ABSTRACTI propose a different account of fictional objects from the ones already present in the literature. According to my account, fictional objects are culturally created abstract objects dependent for their existence on the pretence attitude adopted by a group of people towards a single fictional content. My work is divided into three parts: in the first one, I present how fictional objects come into existence according to my proposal; in the second part, I illustrate how the existence of fictional objects (...) so conceived may be ontically indeterminate; in the last part, I consider what happens when vague existence and indeterminate identity are claimed within fictional texts. (shrink)

The hierarchical analysis of existence attribution is Fregean in its endorsement of senses, understood as guises. Furthermore, the hierarchical analysis makes an essential use of the Russellian analysis (9′) as a means to understand what it is for a sense to present a given entity (cf. biconditional (11) above). The hierarchical analysis, on the other hand, is more general than the Russellian one and hence - in accordance with natural language usage - allows for a wider range of applications.

Konolige''s technical notion of belief based on deduction structures is briefly reviewed and its usefulness for the design of artificial agents with limited representational and deductive capacities is pointed out. The design of artificial agents with more sophisticated representational and deductive capacities is then taken into account. Extended representational capacities require in the first place a solution to the intensional context problems. As an alternative to Konolige''s modal first-order language, an approach based on type-free property theory is proposed. It considers (...) often neglected issues, such as the need for a more general account of thede dicto-de re distinction, and quasi-indicators. Extended deductive capacities require a subdivision of Konolige''s notion of belief into two distinct technical notions,potential anddispositional belief. The former has to do with what an artificial agent could in principle come to actively believe, given enough time and its specific logical competence; the latter with what an agent can be assumed to believe with respect to a specific goal to be fulfilled. (shrink)

ABSTRACT The target article uses the metaphysics of properties to make its meta-ethical claims. This comment discusses two general points in the metaphysics of properties. The first point has to do with the conditions for property identity. Philosophers who accept the existence of properties have proposed a variety of criteria for their identity. The standard Broome applies is medium coarse. Other standards for property identity could be evaluated for their appropriateness for addressing questions in the metaphysics of ethics. Use of (...) a formalized theory of properties might help in such an evaluation. The second point has to do with Broome’s suggestion of a distinction between a property and a reified property. A suggestion will be offered for a range of ways such a distinction could be filled out using the resources of a formalized theory of properties and objects. Objects will be proposed that could serve as Broome’s reified properties. (shrink)

We investigate the form of mathematical structuralism that acknowledges the existence of structures and their distinctive structural elements. This form of structuralism has been subject to criticisms recently, and our view is that the problems raised are resolved by proper, mathematics-free theoretical foundations. Starting with an axiomatic theory of abstract objects, we identify a mathematical structure as an abstract object encoding the truths of a mathematical theory. From such foundations, we derive consequences that address the main questions and issues that (...) have arisen. Namely, elements of different structures are different. A structure and its elements ontologically depend on each other. There are no haecceities and each element of a structure must be discernible within the theory. These consequences are not developed piecemeal but rather follow from our definitions of basic structuralist concepts. (shrink)

Karen Bennett has recently argued that the views articulated by Linsky and Zalta (Philos Perspect 8:431–458, 1994) and (Philos Stud 84:283–294, 1996) and Plantinga (The nature of necessity, 1974) are not consistent with the thesis of actualism, according to which everything is actual. We present and critique her arguments. We first investigate the conceptual framework she develops to interpret the target theories. As part of this effort, we question her definition of ‘proxy actualism’. We then discuss her main arguments that (...) the theories carry a commitment to actual entities that do not exist. We end by considering and addressing a worry that might have been the driving force behind Bennett’s claim that Linsky and Zalta’s view is not fully actualistic. (shrink)

While ante rem structuralism offers a promising account of mathematical truth and mathematical ontology, several of the most prominent formulations of the view seem to be subject to significant difficulties involving the identity conditions of the objects they posit. In this paper I argue that those difficulties can be overcome by adopting encoding structuralism, a version of realism about mathematical objects developed by Bernard Linsky, Uri Nodelman and Edward Zalta.