I am a friend of supervaluationism. A statement lacks a definite truth value if, and only if, it comes out true on some admissible ways of precisifying the semantics of the relevant vocabulary and false on others. In this paper, I focus on the special case of identity statements. I take it that such statements, too, may occasionally suffer a truth-value gap, including philosophically significant instances. Yet there is a potentially devastating objection that can be raised against the supervaluationist treatment (...) of such cases—in fact two objections. Luckily, both can be resisted. But seeing how requires that we take a closer look at the ontological presuppositions of supervaluationism, allowing for more leeway than is usually supposed. (shrink)

A standard response to the problem of diachronic vagueness is ‘the semantic solution’, which demands an abundant ontology. Although it is known that the abundant ontology does not logically preclude endurantism, their combination is rejected because it necessitates massive coincidence between countless objects. In this paper, I establish that the semantic solution is available not only to perdurantists but also to endurantists by showing that there is no problem with such ubiquitous and principled coincidence.

This paper argues against the common practice of presenting perdurantism, endurantism, and other views about persistence and time as solutions to an alleged puzzle about change. Various recent attempts to generate a puzzle about change are examined and found unsuccessful. This does not mean, however, that the relevant views about persistence and time are not well motivated, but rather that their interest and purpose is independent of their suitability for solving the alleged puzzle.

A presentation of the Lewis-Sider argument from vagueness for unrestricted composition and possible responses.

Many of those who accept the universalist thesis that mereological composition is unrestricted also maintain that the folk typically restrict their quantifiers in such a way as to exclude strange fusions when they say things that appear to conflict with universalism. Despite its prima facie implausibility, there are powerful arguments for universalism. By contrast, there is remarkably little evidence for the thesis that strange fusions are excluded from the ordinary domain of quantification. Furthermore, this reconciliatory strategy seems hopeless when applied (...) to the more fundamental conflict between universalism and the intuitions that tell against it. (shrink)

The paper set up a small “philosophical lab” for thought experiments using Digital Universes as its main tool. Digital Universes allow us to examine how mereology affects the debate on New Realism of Ferraris and shed new light on the whole notion of Realism. The semi-formal framework provides a convenient way to model the varieties of realism that are important for the program of New Realism: we then draw the natural consequences of this approach into the ontology of our world, (...) arguing that the same considerations that apply to Digital Universe would hold for chess, institutions and social objects as well. Once a particular version of mereology is chosen, there are unavoidable consequences that the very underlying structure of social ontology. We then propose a new New Realism to tackle social objects: social objects turn out to be nothing more than mereological sums, picked up by some description. (shrink)

The Monster Objection has often been considered one of the main reasons to explore non-standard mereological views, such as hylomorphism. Still, it has been rarely discussed and then only in a cursory fashion. This paper fills this gap by offering the first thorough assessment of the objection. It argues that different metaphysical stances, such as presentism and three- and four-dimensionalism, provide different ways of undermining the objection.

The special composition question is the question, ‘When do some things compose something?’ The answers to this question in the literature have largely been at odds with common sense, either by allowing that any two things compose something, or by denying the existence of most ordinary composite objects. I propose a new ‘series-style’ answer to the special composition question that accords much more closely with common sense, and I defend this answer from van Inwagen's objections. Specifically, I will argue that (...) the proposed answer entails the transitivity of parthood, that it is non-circular, and that it casts some light on the ancient puzzle about the Ship of Theseus. (shrink)

In the past few years, deflationary positions in the debate on the nature of composite material objects have become prominent. According to Ted Sider these include the thesis of quantifier variance, against which he has defended ontological realism. Recently, Sider has considered the possibility of rejecting his arguments against the vagueness of the unrestricted quantifiers in terms of translation functions. Against this strategy, he has presented an intuitive complaint and has argued that it can only be resisted if quantifier variance (...) is accepted. But this is false. In this paper I argue, against Sider, that there is a coherent way to combine the rejection of quantifier variance with the vagueness of the unrestricted quantifiers. I sketch a model to show this, and then I consider, on the basis of it, several versions of the indeterminacy argument against the vagueness of the unrestricted quantifiers that Sider has formulated over the years. (shrink)

My paper provides reasons in support of the view that vague identity claims originate from a conflict between rigidity and precision in designation. To put this stricly, let x be the referent of the referential terms P and Q. Then, that the proposition “that any x being both a P and a Q” is vague involves that the semantic intuitions at work in P and Q reveal a conflict between P and Q being simultaneously rigid and precise designators. After having (...) shortly commented on an example of vague identity claim, I make the case for my proposal, by discussing how reference by baptism conflicts with descriptive attitudes towards understanding conceptual contents. (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)

An encyclopedia entry which covers various revisionary conceptions of which macroscopic objects there are, and the puzzles and arguments that motivate these conceptions: sorites arguments, the argument from vagueness, the puzzles of material constitution, arguments against indeterminate identity, arguments from arbitrariness, debunking arguments, the overdetermination argument, and the problem of the many.

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.

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)

I examine the consistency between contemporary environmentalist ideals and Buddhist philosophy, focusing, first, on the problem of value in nature. I argue that the teachings found in the Pāli canon cannot easily be reconciled with a belief in the intrinsic value of life, whether human or otherwise. This is because all existence is regarded as inherently unsatisfactory, and all beings are seen as impermanent and insubstantial, while the ultimate spiritual goal is often viewed, in early Buddhism, as involving a deep (...) renunciation of the world. Therefore, the discussion focuses mostly on the Mahāyāna vehicle, which, I suggest has better resources for environmentalism because enlightenment and the ordinary world are not conceived as antithetical. Still, many contemporary green ideas do not sit well with classical Mahāyāna doctrines. Mahāyāna philosophers coincide in equating ultimate reality with ‘emptiness,’ and propose knowledge of this reality as a final soteriological purpose. Emptiness is generally said to be ineffable, and to involve the negation of all views. An important question is how to reconcile environmentalism with the relinquishing of views. I consider several prevalent themes in environmentalism, including the philosophy of ‘Oneness,’ and other systems that are often compared with Buddhism, like process thought. Many of these turn out to have more in common with an extreme view that Buddhism seeks to avoid, namely, eternalism. I attempt to outline an environmental position that, like the doctrine of emptiness, traverses a Middle Path between eternalism and nihilism. I conclude by proposing that emptiness could be regarded as the source of value in nature, if it is seen in its more positive aspect, as ‘pliancy.’ This would imply that what Buddhist environmentalists should seek to protect is not any being in its current form, nor any static natural system, but the possibility of adaptation and further evolution. (shrink)

An introduction to the theories of endurantism and perdurantism, and persistence more broadly.

On the opposition between de re and de dicto conceptions of vagueness, with special reference to their bearing on the tasks of ontology.

A critical survey of the main metaphysical theories concerning the nature of material objects (substratum theories, bundle theories, substance theories, stuff theories) and their identity conditions, both synchronic (monist vs. pluralist theories) and diachronic (three-dimensionalism, four-dimensionalism, sequentialism).

According to a popular line of reasoning, diachronic vagueness creates a problem for the endurantist conception of persistence. Some authors have replied that this line of reasoning is inconclusive, since the endurantist can subscribe to a principle of Diachronic Unrestricted Composition (DUC) that is perfectly parallel to the principle required by the perdurantist’s semantic account. I object that the endurantist should better avoid DUC. And I argue that even DUC, if accepted, would fail to provide the endurantist with the necessary (...) resources for explaining diachronic vagueness in familiar semantic terms. (shrink)