Say that some things compose something, if the latter is a whole, fusion, or mereological sum of the former. Then the thesis that composition is identity holds that the composition relation is a kind of identity relation, a plural cousin of singular identity. On this thesis, any things that compose a whole are identical with the whole. This article argues that the thesis is incoherent. To do so, the article formulates the thesis in a plural language, a symbolic language that (...) includes counterparts of plural constructions of natural languages, and shows that it implies that nothing has a proper part. Then the article argues that the thesis, as its proponents take it, is incoherent because they take it to imply or presuppose that some things have proper parts. (shrink)

I propose a new theory of mereology based on a mereological reflection principle. Reflective mereology has natural fusion principles but also refutes certain principles of classical mereology such as Universal Fusion and Fusion Uniqueness. Moreover, reflective mereology avoids Uzquiano’s cardinality problem–the problem that classical mereology tends to clash with set theory when they both quantify over everything. In particular, assuming large cardinals, I construct a model of reflective mereology and second-order ZFCU with Limitation of Size. In the model, classical mereology (...) holds when the quantifiers are restricted to the urelements. (shrink)

Part/whole is said in many ways: the leg is part of the table, the subset is part of the set, rectangularity is part of squareness, and so on. Do the various flavors of part/whole have anything in common? They may be partial orders, but so are lots of non-mereological relations. I propose an “upward difference transmission” principle: x is part of y if and only if x cannot change in specified respects while y stays the same in those respects.

The problem of the many threatens to show that, in general, there are far more ordinary objects than you might have thought. I present and motivate a solution to this problem using many-one identity. According to this solution, the many things that seem to have what it takes to be, say, a cat, are collectively identical to that single cat.

Hume's Dictum (HD) says, roughly and typically, that there are no metaphysically necessary connections between distinct, intrinsically typed, entities. HD plays an influential role in metaphysical debate, both in constructing theories and in assessing them. One should ask of such an influential thesis: why believe it? Proponents do not accept Hume's arguments for his dictum, nor do they provide their own; however, some have suggested either that HD is analytic or that it is synthetic a priori (that is: motivated by (...) intuitions we have no good reason to question). Here I explore whether belief in HD is directly justified on either grounds. I motivate and present more formal characterizations of HD; I show that there are good prima facie cases to be made for HD's being analytic and for its being synthetic a priori; I argue that each of the prima facie cases fails, some things considered. I close by offering two suggestions for how belief in HD might be indirectly justified on argumentative grounds. (shrink)

When it comes to scientific explanation, our parsimonious tendencies mean that we focus almost exclusively on those dispositions whose manifestations result in some sort of change – changes in properties, locations, velocities and so on. Following this tendency, our notion of causation is one that is inherently dynamic, as if the maintenance of the status quo were merely a given. Contrary to this position, I argue that a complete concept of causation must also account for dispositions whose manifestations involve no (...) changes at all, and that a causal theory that fails to include these ‘static’ dispositions alongside the dynamic ones renders static occurrences miraculous. (shrink)

I formulate a theory of groups based on pluralities and counterparts: roughly put, a group is a plurality of entities at a time. This theory comes with counterpart-theoretic semantics for modal and temporal sentences about groups. So this theory of groups is akin to the stage theory of material objects: both take the items they analyze to exist at a single time, and both use counterparts to satisfy certain conditions relating to the modal properties, temporal properties, and coincidence properties of (...) those items. (shrink)

Simon Saunders and David Wallace have proposed an attractive semantics for interpreting linguistic communities embedded in an Everettian multiverse. It provides a charitable interpretation of our ordinary talk about the future, and allows us to retain a principle of bivalence for propositions and to retain the law of excluded middle in the logic of propositions about the future. But difficulties arise when it comes to providing an appropriate account of the metaphysics of macroscopic objects and events. I evaluate various metaphysical (...) frameworks which might be combined with the Saunders–Wallace semantics. I conclude that the most appropriate metaphysics to underwrite the semantics renders Everettian quantum mechanics a theory of non-overlapping worlds. (shrink)

Worlds where things divide forever ("gunk" worlds) are apparently conceivable. The conceivability of such scenarios has been used as an argument against "nihilist" or "near-nihilist" answers to the special composition question. I argue that the mereological nihilist has the resources to explain away the illusion that gunk is possible.

The notion of a proposition is central to philosophy. But it is subject to paradoxes. A natural response is a hierarchical account and, ever since Russell proposed his theory of types in 1908, this has been the strategy of choice. But in this paper I raise a problem for such accounts. While this does not seem to have been recognized before, it would seem to render existing such accounts inadequate. The main purpose of the paper, however, is to provide a (...) new hierarchical account that solves the problem. (shrink)

This paper develops the metaphysical hypothesis that there are irreducibly collective pluralities, pluralities of objects that do not have a singular object among them. A way to formulate this hypothesis using plural quantification will be proposed and the coherence of irreducibly collective existence will be defended. Furthermore, irreducibly collective existence will be shown to allow for bottomless scenarios that do not involve things standing in relations of parthood. This will create logical space for an anti-atomistic form of mereological nihilism.

This essay clarifies quantifier variance and uses it to provide a theory of indefinite extensibility that I call the variance theory of indefinite extensibility. The indefinite extensibility response to the set-theoretic paradoxes sees each argument for paradox as a demonstration that we have come to a different and more expansive understanding of ‘all sets’. But indefinite extensibility is philosophically puzzling: extant accounts are either metasemantically suspect in requiring mysterious mechanisms of domain expansion, or metaphysically suspect in requiring nonstandard assumptions about (...) mathematical objects. Happily, the view of quantifier meanings that underwrites quantifier variance can be used to provide an account of indefinite extensibility that is both metasemantically and metaphysically satisfying. Section 1 introduces the puzzle of indefinite extensibility; section 2 develops and clarifies the metasemantics of quantifier variance; section 3 solves section 1's puzzle of indefinite extensibility by applying section 2's account of quantifier meanings; and section 4 compares the theory developed in section 3 to several other theories in the literature. (shrink)

In many ontological debates there is a familiar challenge. Consider a debate over X s. The “small” or anti-X side tries to show that they can paraphrase the pro-X or “big” side’s claims without any loss of expressive power. Typically though, when the big side adds whatever resources the small side used in their paraphrase, the symmetry breaks down. The big side plus small’s resources is a more expressively powerful and thus more theoretically fruitful theory. In this paper, I show (...) that there is a very general solution to this problem, for the small side. Assuming the resources of set theory, small can successfully paraphrase big. This result depends on a theorem about models of set theory with urelements. After proving this theorem, I discuss some of its philosophical ramifications. (shrink)

The standard account of ontological commitment is quantificational. There are many old and well-chewed-over challenges to the account, but recently Kit Fine added a new challenge. Fine claimed that the ‘‘quantificational account gets the basic logic of ontological commitment wrong’’ and offered an alternative account that used an existence predicate. While Fine’s argument does point to a real lacuna in the standard approach, I show that his own account also gets ‘‘the basic logic of ontological commitment wrong’’. In response, I (...) offer a full quantificational account, using the resources of plural logic, and argue that it leads to a complete theory of natural language ontological commitment. (shrink)

Some philosophers assume that our ordinary parts-whole concepts are intuitive and univocal. Moreover, some assume that mereology—the formal theory of parts-whole relations—adequately captures these intuitive and univocal notions. Lewis, for example, maintains that mereology is “perfectly understood, unproblematic, and certain.” Following his lead, many assume that expressions such as ‘is part of’ are univocal, topic-neutral, and that compositional monism is true. This paper explores the rejection of –. I argue that our ordinary parts-whole expressions are polysemous; they have multiple distinct, (...) but related, interpretations or meanings. I canvass several criteria by which to test for polysemy, and apply these criteria to some of our parts-whole terminology. I also examine some philosophical examples involving abstracta and abstract parts, which give us additional reasons to think that our parts-whole expressions are polysemous and topic-specific. Yet if so, then compositional pluralism is true. (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)

David Lewis insists that restrictivist composition must be motivated by and occur due to some intuitive desiderata for a relation R among parts that compose wholes, and insists that a restrictivist’s relation R must be vague. Peter van Inwagen agrees. In this paper, I argue that restrictivists need not use such examples of relation R as a criterion for composition, and any restrictivist should reject a number of related mereological theses. This paper critiques Lewis and van Inwagen (and others) on (...) their respective mereological metaphysics, and offers a Golden Mean between their two opposite extremes. I argue for a novel account of mereology I call Modal Mereology that is an alternative to Classical Mereology. A modal mereologist can be a universalist about the possible composition of wholes from parts and a restrictivist about the actual composition of wholes from parts. I argue that puzzles facing Modal Mereology (e.g., puzzles concerning Cambridge changes and the Problem of the Many, and how to demarcate the actual from the possible) are also faced in similar forms by classical universalists. On my account, restricted composition is rather motivated by and occurs due to a possible whole’s instantiating an actual type. Universalists commonly believe in such types and defend their existence from objections and puzzles. The Modal Mereological restrictivist can similarly defend the existence of such types (adding that such types are the only wholes) from similar objections and puzzles. (shrink)

Many of us think that ordinary objects – such as tables and chairs – exist. We also think that ordinary objects have parts: my chair has a seat and some legs as parts, for example. But once we are committed to the (seemingly innocuous) thesis that ordinary objects are composed of parts, we then open ourselves up to a whole host of philosophical problems, most of which center on what exactly the composition relation is. Composition as Identity (CI) is the (...) view that the composition relation is the identity relation. While such a view has some advantages, there are many arguments against it. In this essay, I will briefly canvass three different varieties of Composition as Identity, and suggest why one of them should be preferred over the others. Then I will outline several versions of the most common objection against CI. I will suggest how a CI theorist can respond to these charges by maintaining that some of the arguments are invalid. (In part 2, I show how a CI theorist can maintain that the remaining arguments, while valid, are unsound). (shrink)

Many of us think that ordinary objects – such as tables and chairs – exist. We also think that ordinary objects have parts: my chair has a seat and some legs as parts, for example. But once we are committed to the (seemingly innocuous) thesis that ordinary objects are composed of parts, we then open ourselves up to a whole host of philosophical problems, most of which center on what exactly this composition relation is. Composition as Identity (CI) is the (...) view that the composition relation is the identity relation. While such a view has some advantages, there are many arguments against it. In this essay, I discuss several versions of the most common objection against CI, and show how the CI theorist can maintain that these arguments – contrary their initial intuitive appeal – are nonetheless unsound. (shrink)

One of the primary burdens of the mereological nihilist is accounting for our ordinary intuitions about material objects. It certainly *seems* as if I am typing on a keyboard, which has particular keys and buttons as parts. But such intuitions are mistaken if mereological nihilism is right, leading to widespread error. So nihilists often propose paraphrases of our everyday utterances as compensation. Cotnoir aims to deliver a new paraphrase strategy on behalf of the nihilist: one that interprets parthood and composition (...) modally, and interprets (spatial) parts as (modal) counterparts. He advertises this view as the spatial analog of Sider’s stage-theoretic view. Unfortunately, I argue, it isn't. The spatial analog to the above views would be something like the following: individuals are region-bound spatial bits. Certain spatial claims about these objects may be true if the relevant spatial bits have the appropriate spatial counterparts. The table is flat iff the table (a spatial bit) has a spatial counterpart that is flat. That is, spatial *counterparts* make certain spatial claims true. Call this the *bit-theoretic* view. In this paper, I use the bit-theoretic view as a foil for highlighting certain aspects of Cotnoir’s proposal, as well as to show that the very ways in which Cotnoir’s view differs from the bit-theoretic view are ways in which it undermines advantages of nihilism. (shrink)

Many of us think that ordinary objects – such as tables and chairs – exist. We also think that ordinary objects have parts: my chair has a seat and some legs as parts, for example. But once we are committed to the thesis that ordinary objects are composed of parts, we then open ourselves up to a whole host of philosophical problems, most of which center on what exactly the composition relation is. Composition as Identity is the view that the (...) composition relation is the identity relation. While such a view has some advantages, there are many arguments against it. In this essay, I will briefly canvass three different varieties of Composition as Identity, and suggest why one of them should be preferred over the others. Then I will outline several versions of the most common objection against CI. I will suggest how a CI theorist can respond to these charges by maintaining that some of the arguments are invalid. (shrink)

In this review essay, I examine the central tenets of sociologist Dave Elder-Vass’s recent contribution to social ontology, as put forth in his book The Causal Power of Social Structures: Emergence, Structure and Agency. Elder-Vass takes issue with ontological individualists and maintains that social structures exist and have causal powers in their own right. I argue that he fails to establish his main theses: he shows neither that social structures have causal powers “in their own right” (in any sense of (...) this expression) nor that they exist. (shrink)

Peter Simons has argued that the expression ‘the universe’ is not a genuine singular term: it can name neither a single, completely encompassing individual, nor a collection of individuals. (It is, rather, a semantically plural term standing equally for every existing object.) I offer reasons for resisting Simons’s arguments on both scores.

I argue that Universalism (the thesis that mereological composition is unrestricted) entails Extensionalism (the thesis that sameness of composition is sufficient for identity) as long as the parthood relation is transitive and satisfies the Weak Supplementation principle (to the effect that whenever a thing has a proper part, it has another part disjoint from the first).

We tend to talk about (refer to, quantify over) parts in the same way in which we talk about whole objects. Yet a part is not something to be included in an inventory of the world over and above the whole to which it belongs, and a whole is not something to be included in the inventory over and above its constituent parts. This paper is an attempt to clarify a way of dealing with this tension which may be labeled (...) the Minimalist View: An element in the field of a part-whole relation is to be included in an inventory of the world if and only if it does not overlap any distinct element that is itself included in the inventory. (shrink)

The so-called "argument from vagueness", the clearest formulation of which is to be found in Ted Sider’s book Four-dimensionalism, is arguably the most powerful and innovative argument recently offered in support of the view that objects are four-dimensional perdurants. The argument is defective--I submit--and in a number of ways that is worth looking into. But each "defect" corresponds to a model of change that is independently problematic and that can hardly be built into the common-sense picture of the world. So (...) once all the gaps of the argument are filled in, the three-dimensionalist is left with the burden of a response that cannot rely on a passive plea for common sense. The argument is not a threat to common sense as such; it is a threat to the three-dimensionalist faithfulness to common sense. (shrink)

There are conflicting intuitions concerning the status of a boundary separating two adjacent entities (or two parts of the same entity). The boundary cannot belong to both things, for adjacency excludes overlap; and it cannot belong to neither, for nothing lies between two adjacent things. Yet how can the dilemma be avoided without assigning the boundary to one thing or the other at random? Some philosophers regard this as a reductio of the very notion of a boundary, which should accordingly (...) be treated a mere façon de parler. In this paper I resist this temptation and examine some ways of taking the puzzle at face value within a realist perspective—treating boundaries as ontologically on a par with (albeit parasitic upon) extended parts. (shrink)

This paper looks at the question of what regions of space are possibly exactly occupied by a material object.

When viewed as the most comprehensive theory of collections, set theory leaves no room for classes. But the vocabulary of classes, it is argued, provides us with compact and, sometimes, irreplaceable formulations of largecardinal hypotheses that are prominent in much very important and very interesting work in set theory. Fortunately, George Boolos has persuasively argued that plural quantification over the universe of all sets need not commit us to classes. This paper suggests that we retain the vocabulary of classes, but (...) explain that what appears to be singular reference to classes is, in fact, covert plural reference to sets. (shrink)

Thomas Hofweber has written a very rich book. In line with the conviction that ontology should be informed by linguistic considerations, he develops a systematic approach to central ontological questions as they arise in different regions of discourse. More generally, the book seeks to cast light upon the nature of ontology and its proper place in enquiry. His preferred methodology is not without consequence: it promises, for example, to solve what otherwise look like intractable philosophical puzzles raised by arithmetical practice (...) and numerical discourse, and, likewise, his treatment of propositional discourse has ramifications for larger questions to do with the prospects of metaphysical enquiry generally. (shrink)

I present a puzzle for absolutely unrestricted quantification. One important advantage of absolutely unrestricted quantification is that it allows us to entertain perfectly general theories. Whereas most of our theories restrict attention to one or another parcel of reality, other theories are genuinely comprehensive taking absolutely all objects into their domain. The puzzle arises when we notice that absolutely unrestricted theories sometimes impose incompatible constraints on the size of the universe.

Salmon and Soames argue against nominalism about numbers and sentence types. They employ (respectively) higher-order and first-order logic to model certain natural language inferences and claim that the natural language conclusions carry commitment to abstract objects, partially because their renderings in those formal systems seem to do that. I argue that this strategy fails because the nominalist can accept those natural language consequences, provide them with plausible and non-committing truth conditions and account for the inferences made without committing themselves to (...) abstract objects. I sketch a modal account of higher-order quantification, on which instead of ranging over sets, higher order quantifiers are used to make (logical) possibility claims about which predicate tokens can be introduced. This approach provides an alternative account of truth conditions for natural language sentences which seem to employ higher-order quantification, thus allowing the nominalist to evade Salmon’s argument. I also show how the nominalist can account for the occurrence of apparently singular abstract terms in certain true statements. I argue that the nominalist can achieve this by, first, dividing singular terms into real singular terms (referring to concrete objects) and only apparent singular terms (called onomatoids), introduced for the sake of brevity and simplicity, and then providing an account of nominalistically acceptable truth conditions of sentences containing onomatoids. I develop such an account in terms of modally interpreted abstraction principles and argue that applying this strategy to Soames’s argument allows the nominalists to defend themselves. (shrink)

David Lewis has formulated a well-known challenge to his Best System account of lawhood: the content of any system whatever can be formulated very simply if one allows for perverse choices of primitive vocabulary. We show that the challenge is not that dangerous, and that to account for it one need not invoke natural properties or relativized versions of the Best System account. This way, we help to move towards an even better Best System account. We discuss extensions of our (...) strategy to the discussions about the indexicality of the notion of laws of nature, and to another trivialization argument. (shrink)

Baxter (Australas J Philos 79: 449-464, 2001) proposes an ingenious solution to the problem of instantiation based on his theory of cross-count identity. His idea is that where a particular instantiates a universal it shares an aspect with that universal. Both the particular and the universal are numerically identical with the shared aspect in different counts. Although Baxter does not say exactly what a count is, it appears that he takes ways of counting as mysterious primitives against which different numerical (...) identities are defined. In contrast, I defend the idea— suggested, though not quite endorsed, by Baxter himself—that counts are independent dimensions of numerical identity. Different ways of counting are explained by the existence of these different sorts of identity (i.e., counts). For the instantiation of a universal by a particular, I propose one dimension concerned with the individuation of particulars (the p-count) and another dimension concerned with the individuation of universals (the u-count). On that basis, I give a clear definition of cross-count identity that explains its asymmetrical nature (i.e., the fact that particulars instantiate universais, but not vice versa). I extend the theory to a third dimension—that of time, or the t-count—and thereby defend Baxter's ideas on change, and the contingency of instantiation. Baxter (Mind 97(388): 575-582, 1988; Australas J Philos 79: 449-464, 2001) proposes the related idea of composition as (cross-count) identity. Parts are individually cross-count identical with the wholes that they constitute, and they collectively share all aspects across counts with those wholes. I propose an innovation by which totality is shared distinctness across counts. The theory applies to both the totality of particulars that instantiate any given universal, and the totality of parts that constitute any given whole. I argue that this has several advantages over Armstrong's view, which is based on a dubious external totalling relation. I also argue that Armstrong's theory of numbers (or quantities) as internal relations ought to be rejected in favour of an account based on identity and distinctness. The paper concludes with a careful analysis of external relations in Baxter's framework. I argue that we must recognise one further dimension of identity in order to differentiate between, e.g., the aspects of Abelard insofar as he loves Heloise and Abelard insofar as he loves Isobel. Each of these aspects is identical with Abelard and identical with loving-by, yet they must be in some way distinct. I therefore propose the r-count, in which multiple distinct relational properties are the very same relation (-part). The existence of these four independent dimensions explains the fact that particulars, universals, relations, and times are fundamentally different sorts of things in the ontology. Each is individuated with respect to a different dimension of identity. (shrink)

The reviewers Rapaport, Stephanou, Angius, Primiero, and Bringsjord of Turner cover a broad range of topics in the philosophy of computer science. They either challenge the positions outlined in Turner or offer a more refined analysis. This article is a response to their challenges.

Discussion of atomistic and monistic theses about abstract reality.

Characterization of a form of explanation involving grounding on the model of mechanistic causal explanation.

What are the necessary and jointly sufficient conditions for an object's being a simple (an object without proper parts)? According to one prominent view, The Pointy View of Simples, an object is a simple if and only if the region occupied by that object contains exactly one point in space. According to another prominent view, MaxCon, an object is a simple if and only if it is maximally continuous. In this paper, I argue that both of these views are inconsistent (...) with the possibility of discrete space. I then go on to formulate analogues to these two views that are consistent with this possibility, and argue that if we are willing to grant the possibility of discrete space, we should endorse the analogue to The Pointy View of Simples over the analogue to MaxCon. (shrink)

Some hold that musical works are fusions of, or coincide with, their performances. But if performances contain wrong notes, won't works inherit that property? We say ‘no’.

Recently, some mechanists have embraced reductionism and some reductionists have endorsed mechanism. However, the two camps disagree sharply about the extent to which mechanistic explanation is a reductionistic enterprise. Reductionists maintain that cellular and molecular mechanisms can explain mental phenomena without necessary appeal to higher-level mechanisms. Mechanists deny this claim. I argue that this dispute turns on whether reduction is a transitive relation. I show that it is. Therefore, mechanistic explanations at the cellular and molecular level explain mental phenomena. I (...) make my case in part by noting that mechanisms at higher levels are composed of mechanisms at lower levels. Compositional relations are transitive. In addition, they are explanatory. I conclude that there are explanatory linkages from cellular and molecular mechanisms to mental phenomena within a hierarchy of nested mechanisms. (shrink)

The special composition question, which asks under which conditions objects compose a further object, establishes a central debate in modern metaphysics. Recent successes of inductive metaphysics, which studies the implications of the natural sciences for metaphysical problems, suggest that insights into the SCQ can be gained by investigating the physics of composite systems. In this work, I show that the minus first law of thermodynamics, which is concerned with the approach to equilibrium, leads to a new approach to the SCQ, (...) the thermodynamic composition principle : Multiple systems in thermal contact compose a single system. This principle, which is justified based on a systematic classification of possible mereological models for thermodynamic systems, might form the basis of an inductive argument for universalism. A formal analysis of the TCP is provided on the basis of mereotopology, which is a combination of mereology and topology. Here, “thermal contact” can be analyzed using the mereotopological predicate “self-connectedness”. Self-connectedness has to be defined in terms of mereological sums to ensure that scattered objects cannot be self-connected. (shrink)

This study is in two parts. In the first part, various important principles of classical extensional mereology are derived on the basis of a nice axiomatization involving ‘part of’ and fusion. All results are proved here with full Fregean rigor. They are chosen because they are needed for the second part. In the second part, this natural-deduction framework is used in order to regiment David Lewis’s justification of his Division Thesis, which features prominently in his combination of mereology with class (...) theory. The Division Thesis plays a crucial role in Lewis’s informal argument for his Second Thesis in his book Parts of Classes. In order to present Lewis’s argument in rigorous detail, an elegant new principle is offered for the theory that combines class theory and mereology. The new principle is called the Canonical Decomposition Thesis. It secures Lewis’s Division Thesis on the strong construal required in order for his argument to go through. The exercise illustrates how careful one has to be when setting up the details of an adequate foundational theory of parts and classes. The main aim behind this investigation is to determine whether an anti-realist, inferentialist theorist of meaning has the resources to exhibit Lewis’s argument for his Second Thesis—which is central to his marriage of class theory with mereology—as a purely conceptual one. The formal analysis shows that Lewis’s argument, despite its striking appearance to the contrary, can be given in the constructive, relevant logic IR. This is the logic that the author has argued, elsewhere, to be the correct logic from an anti-realist point of view. The anti-realist is therefore in a position to regard Lewis’s argument as purely conceptual. (shrink)

Objective probability in quantum mechanics is often thought to involve a stochastic process whereby an actual future is selected from a range of possibilities. Everett’s seminal idea is that all possible definite futures on the pointer basis exist as components of a macroscopic linear superposition. I demonstrate that these two conceptions of what is involved in quantum processes are linked via two alternative interpretations of the mind-body relation. This leads to a fission, rather than divergence, interpretation of Everettian theory and (...) to a novel explanation of why a principle of indifference does not apply to self-location uncertainty for a post-measurement, pre-observation subject, just as Sebens and Carroll claim. Their Epistemic Separability Principle is shown to arise out of this explanation and the derivation of the Born rule for Everettian theory is thereby put on a firmer footing. (shrink)

The contemporary popularity of semantic externalism has arisen from so-called Twin Earth thought experiments which suggest that the representational content of a natural kind term cannot be wholly determined by processes within a speaker's body. Such arguments depend on the intuition that the extensions of natural kind terms cannot have changed as the result of the scientific investigation of natural kinds' constitutions. I demonstrate that this externalist intuition depends on an assumption about the mentality of isomorphic doppelgangers which has never (...) been questioned but which is nonetheless arguably false. I develop an alternative view of the instantiation of mind which entails a revision of our understanding of the constitution of environmental objects. The picture seems to be fully coherent despite its oddity and I can find no good reason to reject it. The conclusion must be that the case for semantic externalism is thus less compelling than is often supposed. (shrink)

In this paper I offer a partial defence of Armstrong’s totality relation as a solution to the problem of so-called “negative existentials”.

In his ‘Ambitious, Yet Modest, Metaphysics’, Hofweber puts forward arguments against positions in metaphysics that he describes as ‘immodest’; a position he identifies as defended by Jonathan Lowe. In this paper I reply to Hofweber’s arguments, offering a defence of immodest metaphysics of the type practiced by Lowe inter alia.

I argue that mereological nihilism fails because it cannot answer the special arrangement question: when is it true that the xs are arranged F-wise? I suggest that the answers given in the literature fail and that the obvious responses that could be made look to undermine the motivations for adopting nihilism in the first place.

The stage theory is a four-dimensional account of persistence motivatedby the worm theory's inability to account for our intuitions in thecases involving coinciding objects. Like the worm theory, it claimsthat there are objects spread out in time, but unlike the worm theory,it argues that these spacetime worms are not familiar particulars liketables and chairs. Rather, familiar particulars are the instantaneoustemporal slices of worms. In order to explain our intuitions that particulars persist for more than an instant, the stage theory drawson (...) the counterpart theory of modal possibilism, which it is supposedto parallel. In this paper I show how the stage theory presupposes thattime can be divided into instants, which I call the atomistic view oftime. I do this by laying out an alternative theory of the nature oftime, the gunky view, and show that if time is gunky the stage theorycollapses into the worm theory. The deeper problem is that the merepossibility of gunky time would cause the stage theory's parallels topossibilism to break down. I therefore conclude that the stage theoryis committed to the view that time is necessarily atomistic. Finally,in the last section I argue that the fact that the stage theory rulesout a priori the possibility of time being gunky gives us reason toreject it as an account of persistence. (shrink)