This paper is partly inspired by a well-known debate between Ruth Barcan Marcus, Terence Parsons and W. V. 0. Quine in the sixties> concerning the extent to which Quantified Modal Logic is committed to Essentialism; the issue nevertheless goes back to the origins of "analytic philosophy'', to the reflections of Frege, Russell, and the earlier Wittgenstein on the nature of logic. By elaborating on a suggestion by Quine, we purport to show that there is a relevant and interesting way to (...) look at the ontological commitments of logical systems such that they are stronger than they are usually taken to be. (shrink)

Everyone knows what David Lewis' possible worlds are, what role they play in his account of possibility and necessity, and Saul Kripke's criticisms. But what, instead, are Kripke's possible worlds, and what role do they play in his account of possibility and necessity? The answers are not so obvious. Recently, it has even been claimed that, contrary to what is standardly assumed, Kripke's approach to modality has not always been consistently metaphysical. In particular, an interpretation of the famous passage in (...) the preface to Naming and Necessity with Kripke's discussion of the dice example has been put forward, according to which he purports there to clarify the modal notions in terms of that of possible world, model-theoretically construed, in a way which is reminiscent of Carnap's. In this paper, I shall point out some internal difficulties of this interpretation, and offer a different one, according to which in the dice passage Kripke is trying, consistently with his metaphysical approach, to legitimize the technically useful notion of possible world starting from modal notions, to be accounted for in another way (arguably, in an essentialistic framework). My final goal, however, will be philosophical elucidation rather than mere exegesis. Indeed, I am interested in shedding some light on what possible worlds might possibly be, if something like Kripke's metaphysical approach is on the right track. (shrink)

Carnap's theory of descriptions was restricted in two ways. First, the descriptive conditions had to be non-modal. Second, only primitive predicates or the identity predicate could be used to predicate something of the descriptum . The motivating reasons for these two restrictions that can be found in the literature will be critically discussed. Both restrictions can be relaxed, but Carnap's theory can still be blamed for not dealing adequately with improper descriptions.

Modal logic is one of philosophy’s many children. As a mature adult it has moved out of the parental home and is nowadays straying far from its parent. But the ties are still there: philosophy is important to modal logic, modal logic is important for philosophy. Or, at least, this is a thesis we try to defend in this chapter. Limitations of space have ruled out any attempt at writing a survey of all the work going on in our field—a (...) book would be needed for that. Instead, we have tried to select material that is of interest in its own right or exemplifies noteworthy features in interesting ways. Here are some themes that have guided us throughout the writing: • The back-and-forth between philosophy and modal logic. There has been a good deal of give-and-take in the past. Carnap tried to use his modal logic to throw light on old philosophical questions, thereby inspiring others to continue his work and still others to criticise it. He certainly provoked Quine, who in his turn provided—and continues to provide—a healthy challenge to modal logicians. And Kripke’s and David Lewis’s philosophies are connected, in interesting ways, with their modal logic. Analytic philosophy would have been a lot different without modal logic! • The interpretation problem. The problem of providing a certain modal logic with an intuitive interpretation should not be conflated with the problem of providing a formal system with a model-theoretic semantics. An intuitively appealing model-theoretic semantics may be an important step towards solving the interpretation problem, but only a step. One may compare this situation with that in probability theory, where definitions of concepts like ‘outcome space’ and ‘random variable’ are orthogonal to questions about “interpretations” of the concept of probability. • The value of formalisation. Modal logic sets standards of precision, which are a challenge to—and sometimes a model for—philosophy. Classical philosophical questions can be sharpened and seen from a new perspective when formulated in a framework of modal logic. On the other hand, representing old questions in a formal garb has its dangers, such as simplification and distortion. • Why modal logic rather than classical (first or higher order) logic? The idioms of modal logic—today there are many!—seem better to correspond to human ways of thinking than ordinary extensional logic. (Cf. Chomsky’s conjecture that the NP + VP pattern is wired into the human brain.) In his An Essay in Modal Logic (1951) von Wright distinguished between four kinds of modalities: alethic (modes of truth: necessity, possibility and impossibility), epistemic (modes of being known: known to be true, known to be false, undecided), deontic (modes of obligation: obligatory, permitted, forbidden) and existential (modes of existence: universality, existence, emptiness). The existential modalities are not usually counted as modalities, but the other three categories are exemplified in three sections into which this chapter is divided. Section 1 is devoted to alethic modal logic and reviews some main themes at the heart of philosophical modal logic. Sections 2 and 3 deal with topics in epistemic logic and deontic logic, respectively, and are meant to illustrate two different uses that modal logic or indeed any logic can have: it may be applied to already existing (non-logical) theory, or it can be used to develop new theory. (shrink)

To understand the thesis of actualism, consider the following example. Imagine a race of beings — call them ‘Aliens’ — that is very different from any life-form that exists anywhere in the universe; different enough, in fact, that no actually existing thing could have been an Alien, any more than a given gorilla could have been a fruitfly. Now, even though there are no Aliens, it seems intuitively the case that there could have been such things. After all, life might (...) have evolved very differently than the way it did in fact. So in virtue of what is it true that there could have been Aliens when in fact there are none, and when, moreover, nothing that exists in fact could have been an Alien? So-called "possibilists" offer the following answer: ‘It is possible that there are Aliens’ is true because there are in fact individuals that could have been Aliens. At first blush, this might appear directly to contradict the premise that no existing thing could possibly have been an Alien. The possibilist's thesis, however, is that existence, or actuality, encompasses only a subset of the things that, in the broadest sense, are. So for the possibilist, ‘It is possible that there are Aliens’ is true simply in virtue of the fact that there are possible-but-nonactual Aliens, i.e., things that could have existed (but do not) and which would have been Aliens if they had. Actualists reject this answer; they deny that there are any nonactual individuals. Thus, actualism is the philosophical position that everything there is — everything that can in any sense be said to be — exists, or is actual. (shrink)

Three claims about essential properties are frequently advanced in recent discussions: (1) a property belongs essentially to a thing only if that thing would cease to exist without that property, (2) an essential property is explanatory, And (3) an essential property is such that it must belong to everything to which it belongs. I argue that the "only if" in (1) cannot be changed to "if and only if" and (1) needs to be supplemented by (2), And that (2) is (...) an indispensable feature of aristotle's view of essential properties and that it casts doubt on (3), Although (2) is usually assumed to provide a reason for (3). (shrink)

Identities formed with proper names may be contingent. this claim is made first through an example. the paper then develops a theory of the semantics of concrete things, with contingent identity as a consequence. this general theory lets concrete things be made up canonically from fundamental physical entities. it includes theories of proper names, variables, cross-world identity with respect to a sortal, and modal and dispositional properties. the theory, it is argued, is coherent and superior to its rivals, in that (...) it stems naturally from a systematic picture of the physical world. (shrink)

In this paper, I reconstruct Quine’s arguments against quantified modal logic, from the early 1940’s to the early 1960’s. Quine’s concerns were not technical. Quine was looking for a coherent interpretation of quantified-in English modal sentences. I argue that Quine’s main thesis is that the intended objectual interpretation of the quantifiers is incompatible with any semantic reading of the modal operators, for example as expressing analytic necessity, unless the entities in the domain of quantification are intensions, i.e. definitional entities. The (...) difficulty is that it makes no sense to say of an ordinary object that it bears a property necessarily or contingently when the necessity or contingency in question is analytic. However, starting in 1960, Quine claims that quantified-in modal sentences can be coherently interpreted only as essentialist predications. When we say about an object that it necessarily F ’s, we can only coherently mean that it essentially F ’s. In the paper, I argue that adequately qualified the thesis is plausible. Two important qualifications are needed. The first is the assumption that satisfaction is an irreducibly predicative notion, making any explication of satisfaction in terms of truth inadequate. The second is the ontological rejection of purely semantic, i.e. merely definitional, entities. With these qualifications in place, Quine’s rejection of the combination of objectual quantifiers and semantic modalities can be upheld. In this way, we vindicate a qualified version of Quine’s conjecture that quantified modal logic is committed to essentialism. (shrink)

The vision of natural kinds that is most common in the modern philosophy of biology, particularly with respect to the question whether species and other taxa are natural kinds, is based on a revision of the notion by Mill in A System of Logic. However, there was another conception that Whewell had previously captured well, which taxonomists have always employed, of kinds as being types that need not have necessary and sufficient characters and properties, or essences. These competing views employ (...) different approaches to scientific methodologies: Mill’s class-kinds are not formed by induction but by deduction, while Whewell’s type-kinds are inductive. More recently, phylogenetic kinds (clades, or monophyletic-kinds) are inductively projectible, and escape Mill’s strictures. Mill’s version represents a shift in the notions of kinds from the biological to the physical sciences. (shrink)

The simplest quantified modal logic combines classical quantification theory with the propositional modal logic K. The models of simple QML relativize predication to possible worlds and treat the quantifier as ranging over a single fixed domain of objects. But this simple QML has features that are objectionable to actualists. By contrast, Kripke-models, with their varying domains and restricted quantifiers, seem to eliminate these features. But in fact, Kripke-models also have features to which actualists object. Though these philosophers have introduced variations (...) on Kripke-models to eliminate their objectionable features, the most well-known variations all have difficulties of their own. The present authors reexamine simple QML and discover that, in addition to having a possibilist interpretation, it has an actualist interpretation as well. By introducing a new sort of existing abstract entity, the contingently nonconcrete, they show that the seeming drawbacks of the simplest QML are not drawbacks at all. Thus, simple QML is independent of certain metaphysical questions. (shrink)

In this paper, I distinguish two senses of the word ‘essence’ both of which figure prominently in recent analytic metaphysics. To disambiguate, I adopt the terminology of ‘modal essence’ (for how a thing metaphysically must be) and ‘whatness essence’ (for what a thing is). With the help of this terminology, I address Kit Fine’s charge that modal metaphysics in the framework of Saul Kripke’s Naming and Necessity proffers an incorrect conceptual analysis of whatness essence. I show that the charge is (...) baseless, and thus that there is no justification for Fine’s verdict that the Kripkean conception of metaphysics should be given up. (shrink)

A minimal second order modal logic of natural kinds is formulated. Concepts are distinguished from properties and relations in the conceptual-logistic background of the logic through a distinction between free and bound predicate variables. Not all concepts (as indicated by free predicate variables) need have a property or relation corresponding to them (as values of bound predicate variables). Issues pertaining to identity and existence as impredicative concepts are examined and an analysis of mass terms as nominalized predicates for kinds of (...) stuff is proposed. The minimal logic is extendible through a summum genus, an infima species or a partition principle for natural kinds. (shrink)

A novel non-classical mereological concept built up by blending the Metaphysics of Xavier Zubiri and the Quantum Theory of Atoms in Molecules of R. F. W. Bader is proposed. It is argued that this philosophical concept is necessary to properly account for what happens in a chemical reaction. From the topology of the gradient of the laplacian of the electronic charge density, \\) within the QTAIM framework, different “atomic graphs” are found for each atom depending on the molecular context, reflecting (...) how the whole molecule affects each atom. In this way, the whole molecular system imposes certain geometry onto each atom, and every atom exhibits different ontological modality. On the Metaphysical side, for X. Zubiri real things are system of different notes. The physical essence is the subsystem of essential notes with a coherence unity. Every note is grounded on the essence. The unity of the system is present somehow in every note-of beforehand, and every essential note-of turns towards the other. The essence determines the position of each note within the system, and hence is the grounding for modality of the notes. By conflating both “theories” and taking the atoms as essential notes, we propose the concept of “Molecule in atoms-of” or “atoms-of in Molecules”. Within the course of a chemical reaction the atoms-of modified their “of” as required by the new molecular unity being formed, and eventually change their modality. The validity to the Zubiri’s statements, is attained by evaluating necessity and possibility in a set-up of finite accessible “possible worlds”. (shrink)

According to the modal view, essence admits of reductive analysis in exclusively modal terms. Fine (1994) argues that modal view delivers an inadequate analysis of essence. This paper defends the modal view from Fine's challenge. This defense proceeds by examining the disagreement between Finean primitivists and Quinean eliminativists about essence. In order to model this disagreement, a distinction between essence and a separable concept, nature, is required. This distinction is then used to show that Fine's challenge is misdirected and therefore (...) unsuccessful. (shrink)

Le nominalisme est « le refus d'admettre toute entité autre qu'indivi-duelle ». II doit, pour justifier la simplicité de son ontologie, proposer une théorie de laconnaissance et une théorie sémantique qui ne présupposent ni l'une ni l'autre l'existence réelle des univer-saux. Certaines des voies qui s'ouvrent à cette entreprise délicate ont été systématiquement explorées vers la fin du Moyen Age et il y a tout à parier que, malgré les ruptures épistémologiques, les révolutions scientifiques et autres changements d'epistémè, les nominalistes (...) contemporains pourraient encore profiter de quelque façon de l'immense travail théorique accompli par leurs prédécesseurs médiévaux. C'est dans cet esprit que je voudrais procéder à une reconstruction sommaire de la théorie sémantique avancée au début du quatorzième siècle par le Fran-ciscain Guillaume d'Occam. Je ne m'engagerai pas dans une comparaison détaillée entre Occam et les auteurs contemporains, mais j'essaierai de présenter sans en trahir l'esprit la sémantique occa-miste de manière à en faire apparaître la pertinence pour les débats actuels. II serait possible, me semble-t-il, d'aller encore plus loin dans cette voie en mettant à profit les techniques formelles récentes pour axiomatiser la théorie d'Occam. Pour l'instant cependant, je me limiterai à une présentation plutôt informelle. (shrink)

According to sparse modalism, the notion of essence can be analysed in terms of necessity and naturalness. In this paper, I develop and defend a version of sparse modalism that is equipped with a non-standard, relativized conception of naturalness. According to this conception, properties and relations can be natural to different degrees relative to different kinds of things, and relations can be natural to different degrees relative to different slots. I argue that this relativized version of sparse modalism can accommodate (...) various cases that the standard, non-relativized version can’t. The alternative version can accommodate cases where a relation is essential to a relatum but merely necessary to another, cases where a property is essential to an object but merely necessary to another, and cases where a less-than-perfectly natural property is essential to an object. (shrink)

In the Twentieth Century, Logic and Philosophy of Language are two of the few areas of philosophy in which philosophers made indisputable progress. For example, even now many of the foremost living ethicists present their theories as somewhat more explicit versions of the ideas of Kant, Mill, or Aristotle. In contrast, it would be patently absurd for a contemporary philosopher of language or logician to think of herself as working in the shadow of any figure who died before the Twentieth (...) Century began. Advances in these disciplines make even the most unaccomplished of its practitioners vastly more sophisticated than Kant. There were previous periods in which the problems of language and logic were studied extensively (e.g. the medieval period). But from the perspective of the progress made in the last 120 years, previous work is at most a source of interesting data or occasional insight. All systematic theorizing about content that meets contemporary standards of rigor has been done subsequently. (shrink)

This paper examines and discusses an argument for the collapse of modal distincions offered by Quine in "Reference and Modality" and in Word and Object that relies exclusively on a version of the Principle of Substitution. It is argued that the argument does not affect its historical targets: Carnap's treatment of modality, presented in Meaning and Necessity, and Church's Logic of Sense and Denotation, developed by Kaplan; nor does it affect a treatment of modality inspired in Frege's treatment of oblique (...) contexts. It is argued, nevertheless, that the immunity of those systems to Quine's argument depends on the success of their rejection of the Principle of Substitution presupposed by Quine. (shrink)

In his paper, “Identity Statements and Essentialism,” Loux seeks to demonstrate sortal essentialism based on Frege’s thesis that all statements of number concerning a collection require that the members fall under the same sortal concept. I shall attempt to argue that a detailed analysis of Loux’s argument reveals it as failing to imply the type of sortal dependency thesis necessary for the justification of sortal essentialism. However, if one construes the transworld identity relation as no different from our run of (...) the mill identity relation, then his argument can serve as the basis for a proof of a type of nontrivial essentialism, thereby showing that the possible worlds picture of modality is indeed committed to a robust essentialism. (shrink)

A number of areas of biology raise questions about what is of value in the natural environment and how we ought to behave towards it: conservation biology, environmental science, and ecology, to name a few. Based on my experience teaching students from these and similar majors, I argue that the field of environmental ethics has much to teach these students. They come to me with pent-up questions and a feeling that more is needed to fully engage in their subjects, and (...) I believe some exposure to environmental ethics can help focus their interests and goals. I identify three primary areas in which environmental ethics can con- tribute to their education. The first is an examination of who (or what) should be considered to be part of our moral community (i.e., the community to whom we owe direct duties). Is it humans only? Or does it include all sentient life? Or all life? Or ecosystems considered holistically? Often, readings implicitly assume one or more of these answers; the goal is to make the student more sensitive to these implicit claims and to get them to think about the different reasons that support them. The second area, related to the first, is the application of the different answers concerning the extent of the ethical community to real environmental issues and problems. Students need to be aware of how the different answers concerning the moral community can imply conflicting answers for how we should act in certain cases and to think about ways to move toward conflict resolution. The third area in which environmental ethics can contribute is a more conceptual one, focusing on central concepts such as biodiversity, sustainability, species, and ecosystems. Exploring and evaluating various meanings of these terms will make students more reflective and thoughtful citizens and biologists, sensitive to the implications that different conceptual choices make. (shrink)

Today there appears to be a widespread impression that W. V. Quine's notorious critique of modal logic, based on certain ideas about reference, has been successfully answered. As one writer put it some years ago: “His objections have been dead for a while, even though they have not yet been completely buried.” What is supposed to have killed off the critique? Some would cite the development of a new ‘possible-worlds’ model theory for modal logics in the 1960s; others, the development (...) of new ‘direct’ theories of reference for names in the 1970s.These developments do suggest that Quine's unfriendliness towards any formal logics but the classical and indifference towards theories of reference for any singular terms but variables were unfortunate. (shrink)

Theories about the ontological structure of the world have generally been described in informal, intuitive terms. This book offers an account of the general features and methodology of formal ontology. The book defends conceptual realism as the best system to adopt based on a logic of natural kinds. By formally reconstructing an intuitive, informal ontological scheme as a formal ontology we can better determine the consistency and adequacy of that scheme.

De re modality is eliminable if there is an effective translation of all wffs into non-de re equivalents. We cannot have logical equivalence unless 'logic' has odd theses, but we can have material equivalence by banning all essences, something the nonde re facts let us do, or by giving everything such humdrum essences as self-identity and banning the more interesting ones. Eliminability cannot be got from weaker assumptions, nor independent ones of even modest generality. The net philosophical import is that, (...) quite apart from the merits of essentialism, de re language has scant utility. (shrink)

El artículo discute la formulación de Marcus del principio de sustituibilidad. Se apoyó en una noción de forma lógica en la que el análisis elimina algunos tipos problemáticos de contexto. Defiendo una formulación variante del principio en la cual los contextos problemáticos se acomodan por derecho propio.

I discuss Stalnaker’s views on modality. In particular, his views on actualism, anti-essentialism, counterpart theory, and the Barcan formulas.

Some wag reported the following story: Scholars have recently established that the Iliad and the Odyssey were not, after all, written by Homer. They were actually written by another author, of the same name.The majority of current theories of naming and reference, including ones as divergent in other respects as those of Russell and Searle, would rule this story impossible. They would do so on roughly these grounds: the sense and reference of the name ‘Homer’ is determined, given the absence (...) of other reliable testimony, by the sole description: ‘Author of the Iliad and the Odyssey’. ‘Homer is the author of the Iliad and the Odyssey’ is therefore known a priori, hence necessarily true. There could not be another author of that name and claim to fame.In lectures delivered at Princeton in the Winter of 1970, Saul Kripke offered a lucid alternative to such theories. (shrink)