In “Proof-Theoretic Justification of Logic”, building on work by Dummett and Prawitz, I show how to construct use-based meaning-theories for the logical constants. The assertability-conditional meaning-theory takes the meaning of the logical constants to be given by their introduction rules; the consequence-conditional meaning-theory takes the meaning of the logical constants to be given by their elimination rules. I then consider the question: given a set of introduction rules \, what are the strongest elimination rules that are validated by an assertability (...) conditional meaning-theory based on \? I prove that the intuitionistic introduction rules are the strongest rules that are validated by the intuitionistic elimination rules. I then prove that intuitionistic logic is the strongest logic that can be given either an assertability-conditional or consequence-conditional meaning-theory. In “Grounding Grounding” I discuss the notion of grounding. My discussion revolves around the problem of iterated grounding-claims. Suppose that \ grounds \; what grounds that \ grounds that \? I argue that unless we can get a satisfactory answer to this question the notion of grounding will be useless. I discuss and reject some proposed accounts of iterated grounding claims. I then develop a new way of expressing grounding, propose an account of iterated grounding-claims and show how we can develop logics for grounding. In “Is the Vagueness Argument Valid?” I argue that the Vagueness Argument in favor of unrestricted composition isn’t valid. However, if the premisses of the argument are true and the conclusion false, mereological facts fail to supervene on non-mereological facts. I argue that this failure of supervenience is an artifact of the interplay between the necessity and determinacy operators and that it does not mean that mereological facts fail to depend on non-mereological facts. I sketch a deflationary view of ontology to establish this. (shrink)

O desenvolvimento da filosofia acadêmica no Brasil é direcionada, entre vários fatores, pelas investigações dos diversos Grupos de Trabalho (GTs) da Associação Nacional de Pós-Graduação em Filosofia (ANPOF). Esses GTs se dividem de acordo com a temática investigada. O GT de Metafísica Analítica é relativamente novo e ainda tem poucos membros, mas os temas nele trabalhados são variados e todos centrais no debate metafísico contemporâneo internacional. A sua investigação se caracteriza pelo rigor lógico e conceitual com o qual aborda esses (...) tradicionais tópicos da metafísica. Embora os assuntos tratados tenham sido, em sua grande maioria, tópicos abordados e discutidos em reuniões remotas do GT, nem todos os membros do nosso grupo estão aqui representados. Esperamos apresentar seus trabalhos em futuros livros. Por enquanto, queremos apenas divulgar ao público acadêmico algumas de nossas produções, trabalhadas e produzidas exclusivamente para este livro. Segundo a caracterização tradicional, com a qual plenamente concordamos, a metafísica se ocupa com a natureza mais íntima e geral da realidade. Essa metafísica é, por um lado, ambiciosa: não pretende apenas expor a realidade segundo o modo como ela se apresenta para nós, mas como ela é ‘em si mesma’. Por outro lado, ela é modesta: ela sabe da sua dívida para com as outras disciplinas, especialmente lógica, linguagem e epistemologia. Além disso, ela se entende como sempre tentativa, provisória, aberta a críticas e revisões. Neste livro, tratamos temas como as categorias ontológicas fundamentais e as suas relações de dependência e de fundamentalidade, a natureza da composição mereológica, da persistência temporal e do próprio tempo, a natureza dos objetos abstratos e dos mundos possíveis, as naturezas do mundo quântico, da causalidade nômica do mundo físico, e, finalmente, de um dos objetos mais característicos da presença humana no nosso mundo físico, que é o objeto de arte. É claro que essa coletânea está longe de apresentar exaustivamente todos os tópicos da metafísica. Tentamos selecionar e organizar os textos da forma mais fluida possível, de modo que eles possam levar tanto a uma reflexão específica quanto a uma reflexão geral sobre a natureza da realidade. Ainda que tenha uma inerente incompletude, o livro serve à finalidade de levar o/a estudante de graduação e pós-graduação a refletir sobre temas contemporâneos da Metafísica Analítica. Justamente por ter esse objetivo de formentar a pesquisa em metafísica analítica nacional, optamos por traduzir muitos termos do inglês que ainda não tem uma tradução canônica, a fim de evitar anglicismos e contribuir para uma leitura mais natural. Muito mais do que leitores complacentes, esse livro pede por leitores críticos, debatedores corajosos, que estejam dispostos a contribuir e a propor novas teorias e argumentos. Agradecemos a todos os membros do GT de Metafísica Analítica da ANPOF e a todos os autores deste livro, que decidiram apresentar publicamente suas pesquisas à academia; aos membros do Grupo de Pesquisa Investigação Filosófica, que decidiram pela publicação deste livro; à Pró-Reitoria de PósGraduação e Pesquisa da Universidade Federal do Amapá, que o financiou; e ao NEPFIL Online e à Editora da UFPel, que o editaram e publicaram. [Guido Imaguire e Rodrigo Reis Lastra Cid, Organizadores] . (shrink)

Words, languages, symphonies, fictional characters, games, and recipes are plausibly abstract artifacts— entities that have no spatial location and that are deliberately brought into existence as a result of creative acts. Many accept that composition is unrestricted: for every plurality of material objects, there is a material object that is the sum of those objects. These two views may seem entirely unrelated. I will argue that the most influential argument against restricted composition—the vagueness argument—doubles as an argument that there can (...) be no abstract artifacts. There is no way to resist the vagueness argument against abstract artifacts that does not also undermine the vagueness argument against restricted composition. (shrink)

This paper consists of two parts. The first concerns the logic of vagueness. The second concerns a prominent debate in metaphysics. One of the most widely accepted principles governing the ‘definitely’ operator is the principle of Distribution: if ‘p’ and ‘if p then q’ are both definite, then so is ‘q’. I argue however, that epistemicists about vagueness should reject this principle. The discussion also helps to shed light on the elusive question of what, on this framework, it takes for (...) a sentence to be borderline or definite. In the second part of the paper, I apply this result to a prominent debate in metaphysics. One of the most influential arguments in favour of Universalism about composition is the Lewis-Sider argument from vagueness. An interesting question, however, is whether epistemicists have any particular reasons to resist the argument. I show that there is no obvious reason why epistemicists should resist the argument but there is a non-obvious one: the rejection of Distribution argued for in the first part of the paper provides epistemicists with a unique way of resisting the argument from vagueness. (shrink)

One of the central debates in contemporary metaphysics has been the debate between endurantism and perdurantism about persistence. In this paper I argue that much of this debate has been misconstrued: most of the arguments in the debate crucially rely on theses which are strictly orthogonal to the endurantism/perdurantism debate. To show this, I note that the arguments in the endurantism/perdurantism debate typically take the following form: one presents a challenge that endurantists allegedly have some trouble addressing, and to which (...) perdurantism apparently has a straightforward response. I argue, however, that in each case, there are versions of endurantism that can offer precisely the same response to the challenge, and thus the ability to provide this particular solution does not directly tell in favour of one the two views. In §1, I elaborate two views which will be particularly prominent in the discussion: liberal endurantism and restrictive perdurantism. In §2–6 I discuss in turn the central pro-perdurantism arguments: the argument from anthropocentricism, the argument from vagueness, the argument from recombination, the argument from temporary intrinsics, and the argument from coincidence. In §7–8, I discuss the main pro-endurantism arguments: the arguments from motion, and the argument from permanent coincidence. Finally, in §9, I discuss what conclusion can be drawn from this discussion. (shrink)

David Lewis (1986) criticizes moderate views of composition on the grounds that a restriction on composition must be vague, and vague composition leads, via a precisificational theory of vagueness, to an absurd vagueness of existence. I show how to resist this argument. Unlike the usual resistance, however, I do not jettison precisificational views of vagueness. Instead, I blur the connection between composition and existence that Lewis assumes. On the resulting view, in troublesome cases of vague composition, there is an object, (...) which definitely exists, about which it is vague whether the relevant borderline parts compose it. (shrink)

How does vagueness interact with metaphysical modality and with restrictions of it, such as nomological modality? In particular, how do definiteness, necessity (understood as restricted in some way or not), and actuality interact? This paper proposes a model-theoretic framework for investigating the logic and semantics of that interaction. The framework is put forward in an ecumenical spirit: it is intended to be applicable to all theories of vagueness that express vagueness using a definiteness (or: determinacy) operator. We will show how (...) epistemicists, supervaluationists, and theorists of metaphysical vagueness like Barnes and Williams (2010) can interpret the framework.  We will also present a complete axiomatization of the logic we recommend to both epistemicists and local supervaluationists. . (shrink)

Mereological nihilism is the view that no objects have proper parts. Despite how counter‐intuitive it is, it is taken quite seriously, largely because it solves a number of puzzles in the metaphysics of material objects – or so its proponents claim. In this article, I show that for every puzzle that mereological nihilism solves, there is a similar puzzle that (a) it doesn’t solve, and (b) every other solution to the original puzzle does solve. Since the solutions to the new (...) puzzles apply just as well to the old puzzles, the old puzzles provide no motivation to be a mereological nihilist. (shrink)

On the standard view for something to exist is for one thing to exist: in slogan form, to be is to be countable. E.J. Lowe argues something can exist without being countable as one, however. His primary example is homogenous “stuff,” i.e., qualitatively uniform and infinitely divisible matter. Lacking nonarbitrary boundaries and being everywhere the same, homogenous stuff lacks a principle of individuation that would yield countably distinct constituents. So, for Lowe, homogenous stuff is strongly uncountable. Olson rejects Lowe’s view (...) and defends the orthodox connection between existence and number. He argues that if there is any stuff, there is a number of portions of stuff. Sider also rejects a stuff ontology, claiming it is incompatible with his preferred view that the familiar quantifiers of predicate logic carve at nature’s joints. Against these arguments, I defend the uncountability of stuff and the possibility of existence without countability. If to be is to be countable, more is needed than the arguments that Olson and Sider provide. (shrink)

When some objects are the parts of another object, they compose that object and that object is composite. This article is intended as an introduction to the central questions about composition and a highly selective overview of various answers to those questions. In §1, we review some formal features of parthood that are important for understanding the nature of composition. In §2, we consider some answers to the question: which pluralities of objects together compose something? As we will see, the (...) dominant answers are all of them and none of them. In §§3-4, we examine one of the main arguments that has driven philosophers to these extreme answers: the argument from vagueness. In §5, we turn to the question of whether composition is unique: is it sometimes the case that some things compose more than one thing? Finally, in §6, we turn from the question of which composites exist to the question of which composites exist fundamentally. (shrink)

Ethics in the tradition of Derek Parfit’s Reasons and Persons is riddled with sorites-like arguments, which lead us by what seem innocent steps to seemingly false conclusions. Take, for example, spectrum arguments for the Repugnant Conclusion that appeal to slight differences in quality of life. Several authors have taken the view that, since spectrum arguments are structurally analogous to sorites arguments, the correct response to spectrum arguments is structurally analogous to the correct response to sorites arguments. I argue against this (...) sorites analogy. I first consider some potential structural disanalogies between spectrum arguments and sorites arguments. But even if these arguments are relevantly structurally analogous, they differ in their content in ways that show the sorites analogy to be implausible. I explore two content-based disanalogies—one is inspired by Parfit’s work on reductionism, and the other involves what I call hypersensitivity. I conclude with a methodological lesson. (shrink)

Material objects extend through space by having different spatial parts in different places. But how do they persist through time? According to some philosophers, things have temporal parts as well as spatial parts: accepting this is supposed to help us solve a whole bunch of metaphysical problems, and keep our philosophy in line with modern physics. Other philosophers disagree, arguing that neither metaphysics nor physics give us good reason to believe in temporal parts.

One of the most influential arguments in favour of perdurantism is the Argument from Vagueness. The argument proceeds in three stages: The first aims to establish atemporal universalism. The second presents a parallel argument in favour of universalism in the context of temporalized parthood. The third argues that diachronic universalism entails perdurantism. I offer a novel objection to the argument. I show that on the correct way of formulating diachronic universalism the principle does not entail perdurantism. On the other hand, (...) if diachronic universalism is formulated as Sider proposes, the argument fails to establish his principle, and thus perdurantism. (shrink)

A world where there exists n concrete things is a count-determinate world. The orthodox view is count-determinacy is necessary; if to be is to be the value of a variable and the domain of quantification is enumerable, count-determinacy follows. Yet I argue how many there are can be indeterminate; count-indeterminacy is metaphysically possible and even likely actual. Notably, my argument includes rebuttals of Evans’ reductio of indeterminate identity and the Lewis/Sider ‘argument from vagueness’. Count-indeterminacy should therefore be recognized as another (...) basic form of genuine metaphysical indeterminacy, in addition to types recently defend by Barnes, Williams, and Wilson. (shrink)

Composition as Identity is the view that an object is identical to its parts taken collectively. I elaborate and defend a theory based on this idea: composition is a kind of identity. Since this claim is best presented within a plural logic, I develop a formal system of plural logic. The principles of this system differ from the standard views on plural logic because one of my central claims is that identity is a relation which comes in a variety of (...) forms and only one of them obeys substitution unrestrictedly. I justify this departure from orthodoxy by showing some problems which result from attempts to avoid inconsistencies within plural logic by means of postulating other non-singular terms besides plural terms. Thereby, some of the main criticisms raised against Composition as Identity can be addressed. Further, I argue that the way objects are arranged is relevant with respect to the question which object they compose, i.e. to which object they are identical to. This helps to meet a second group of arguments against Composition as Identity. These arguments aim to show that identifying composite objects on the basis of the identity of their parts entails, contrary to our common sense view, that rearranging the parts of a composite object does not leave us with a different object. Moreover, it allows us to carve out the intensional aspects of Composition as Identity and to defend mereological universalism, the claim that any objects compose some object. Much of the pressure put on the latter view can be avoided by distinguishing the question whether some objects compose an object from the question what object they compose. Eventually, I conclude that Composition as Identity is a coherent and plausible position, as long as we take identity to be a more complex relation than commonly assumed. (shrink)

Mereological universalists, according to whom every plurality of entities has a fusion, usually claim that most quantifications are restricted to ordinary entities. However, there is no evidence that our usual quantifications over ordinary objects are restricted. In this article I explore an alternative way of reconciling Mereological Universalism with our usual quantifications. I resort to a modest form of ontological expansionism and to the so-called interpretational modalities. Quantifications over ordinary objects are the initial stages of the expansion. From these initial (...) stages, expansions can proceed upwards (fusions of entities in the domain of quantification are added), downwards (parts of entities in the domain are added), and sidewards (entities which are mereologically disjoint from the entities in the domain are added). These expansions are driven by a variety of epistemic and pragmatic reasons and raise different kinds of problems. At each stage, a modalized version of Mereological Universalism is true. By contrast, only at some especially rich stages, standard, non-modalized Mereological Universalism is true as well. Among these especially rich stages, there is a final, metaphysically pre-eminent stage of mereological plenitude. In the last part of the article I discuss some problems and limitations of expansionism. (shrink)

An overview of contemporary part-whole theories, with reference to both their axiomatic developments and their philosophical underpinnings.

Ted Sider has famously argued that existence, in the unrestricted sense of ontology, cannot be vague, as long as vagueness is modeled by means of precisifications. The first section of Chapter 9 exposes some controversial assumptions underlying Sider’s alleged reductio of vague existence. The upshot of the discussion is that, although existence cannot be vague, it can be super-vague, i.e. higher-order vague, for all orders. The second section develops and defends a novel framework, dubbed negative supervaluationary semantics, which makes room (...) for the possibility of super-vague existence. (shrink)

It has been argued by some that the argument from vagueness is one of the strongest arguments in favor of the theory of temporal parts. I will neither support nor dispute this claim here. Rather, I will present a version of the argument from vagueness, which – if successful – commits one to the existence of modal parts. I argue that a commitment to the soundness of the argument from vagueness for temporal parts compels one to commit to the soundness (...) of the argument from vagueness for modal parts. I say compels, but not entails; an objection to one of the arguments highlights analogous ways to reject the other, making it difficult to endorse one and reject the other. This would be a significant conclusion, if true, since there are far fewer who currently commit themselves to modal parts than the many who currently commit themselves to temporal parts. (shrink)