According to structuralism, all natural properties are individuated by their roles in causal/nomological structures. According to quidditism, at least some natural properties are individuated in some other way. Because these theses deal with the identities of natural properties, this distinction cuts to the core of a serious metaphysical dispute: Are the intrinsic natures of all natural properties essentially causal/nomological in character? I'll argue that the answer is ‘no’, or at least that this answer is more plausible than many critics of (...) quidditism have recognized. In section 1, I distinguish between two versions of quidditism. Bare quidditism holds that worlds with distinct properties and isomorphic structures must be qualitatively identical in the following sense: inhabiting one world would be indistinguishable from inhabiting the other. In contrast, qualitative quidditism allows such worlds to have qualitative differences. In section 2, I discuss an epistemological position that allows us to bett... (shrink)

According to dispositionalism, fundamental properties are dispositions—powers that don’t reduce to other properties, laws, or anything else. As dispositions manifest, natural regularities result, so this view appears to explain the uniformity of nature. However, in this paper I’ll argue that there are types of regularities that can’t be explained by dispositionalism. The basic idea is this. All accounts of fundamental dispositions endow properties with a certain sort of structure. This allows explanations of only those regularities that align with such structures. (...) In this paper, I identify a type of natural regularity that cannot fit dispositionalist structures and show why the possibility of such regularities is problematic. (shrink)

This paper has two main aims. The first is to present a general approach for understanding “dispositional” and “categorical” properties; the second aim is to use this approach to criticize Russellian Monism. On the approach I suggest, what are usually thought of as “dispositional” and “categorical” properties are really just the extreme ends of a spectrum of options. The approach allows for a number of options between these extremes, and it is plausible, I suggest, that just about everything of scientific (...) interest falls in this middle ground. I argue that Russellian Monism depends for its plausibility on the unarticulated assumption that there are no properties in the middle ground. (shrink)

Objectivism about evidential support is the thesis that facts about the degree to which a body of evidence supports a hypothesis are objective rather than depending on subjective factors like one’s own language or epistemic values. Objectivism about evidential support is key to defending a synchronic, time-slice-centric conception of epistemic rationality, on which what you ought to believe at a time depends only on what evidence you have at that time, and not on how you were at previous times. Here, (...) I defend a version of objectivism about evidential support on which facts about evidential support are grounded in facts about explanatoriness. (shrink)

It is widely agreed that properties play causal roles: they capture the causal powers of things. But do properties have their causal roles essentially? David Lewis did not think so. He adhered to the doctrine of quidditism, namely the doctrine that the identity of properties is primitive and that they can trade their causal roles. Quidditism is controversial. But Lewis did not see why he should want to reject it. He knew that he could avoid quidditism on the cheap by (...) treating individuals and properties alike in rejecting transworld multilocation of properties and endorsing a counterpart theory for properties. But he did not see why he should want to do so. In this article, I argue that Lewis should have wanted to endorse a counterpart theory for properties in order to reject quidditism. My argument concerns resemblance relations among properties. Another constitutive role of properties is that they capture objective resemblances between their instances. The premises of my argument are intuitive claims about resemblances among some properties that Lewis held on Humean grounds. (shrink)

In this paper I argue that bodily pain, as a phenomenal property, is an essentially and substantial dispositional property. To this end, I maintain that this property is individuated by its phenomenal roles, which can be internal -individuating the property per se- and external -determining further phenomenal or physical properties or states. I then argue that this individuation allows phenomenal roles to be organized in a necessarily asymmetrical net, thereby overcoming the circularity objection to dispositionalism. Finally, I provide reasons to (...) argue that these roles satisfy modal fixity, as posited by Bird, and are not fundamental properties, contra Chalmers’ panpsychism. Thus, bodily pain can be considered a substantial dispositional property entrenched in non-fundamental laws of nature. (shrink)

According to non-reductive physicalism, mental properties of the phenomenal sort are essentially different from physical properties, and cannot be reduced to them. This being a quarrel about properties, I draw on the categorical / dispositional distinction to discuss this non-reductive claim. Typically, non-reductionism entails a categorical view of phenomenal properties. Contrary to this, I will argue that phenomenal properties, usually characterized by what it is like to have them, are mainly the manifestation of dispositional properties. This paper is thus divided (...) into two parts. In the first part, after tracing a working distinction between categorical and dispositional properties, I argue that there is a form of incoherence looming behind the idea of taking phenomenal properties as categorical. In the second part, I argue in favor of the view that phenomenal properties are dispositional properties with an essential manifestation. This interpretation allows us to broaden dispositionalism so as to include the sciences of mind, thus ultimately favoring a physicalist view on the mind. (shrink)

According to David Lewis’s Modal Realism, other possible worlds really exist as concrete, spatiotemporal systems, and every way that a world could be is a way that some world is. To establish this plenitude of concrete possible worlds, Lewis presents his ‘principle of recombination,’ which is meant to guarantee that there exists a possible world, or part of a possible world, for every possibility. Jessica Wilson has recently argued that Lewis’s principle of recombination fails to generate enough worlds to account (...) for the plenitude of possibilities. Namely, Wilson argues that the principle of recombination cannot account for the possibility of spatially overlapping but distinct fundamental entities, as well as certain macroscopic entities. In this paper, I will defend Lewis’s principle of recombination against these charges, arguing that Wilson’s objections overlook features of Lewisian metaphysics that can solve the problems at hand. (shrink)

Dispositionality and qualitativity are key notions to describe the world that we inhabit. Dispositionality is a matter of what a thing is disposed to do in certain circumstances. Qualitativity is a matter of how a thing is like. According to the Identity Theory of powers, every fundamental property is at once dispositional and qualitative, or a powerful quality. Canonically, the Identity Theory holds a contentious identity claim between a property’s dispositionality and its qualitativity. In the literature, this view faces a (...) contradiction objection that undermines its merits. We should therefore consider an alternative version that does not embrace the identity claim. My aim is to show that we can enjoy the benefits of the Identity Theory without embracing the identity between the dispositional and the qualitative. I shall argue that a distinction between two senses of dispositionality and qualitativity serves the purpose. I will then discuss three readings of the identity claim that can be formulated in light of such a distinction. I will conclude that even if the identity were to fail in any of the suggested readings, it would be possible to hold an account of fundamental powerful qualities. (shrink)

Dispositional essentialism is the view that all or many fundamental properties are essentially dispositional, orpowers. The literature on the dispositional essence of powers is abundant. In contrast, the question of how to understand the fundamentality of fundamental powers has received scarce interest. Therefore, the fundamentality of powers stands in need of clarification. There are four main conceptions of the fundamental, namely as that which is (i)metaphysically independent; or (ii)belonging to a minimally complete basis; or (iii)perfectly natural; or (iv)metaphysically primitive. Here, (...) I present and discuss each of these approaches from the viewpoint of dispositional essentialism. I show that (i) is incompatible with the metaphysics of powers and (ii)–(iv) have more drawbacks than merits. Therefore, my conclusion is that the dispositional essentialist should seek an alternative. Although I offer no positive account, I pave the way to more fruitful views by identifying the shortcoming of these unpromising options. (shrink)

Metaphilosophy, Volume 53, Issue 1, Page 85-99, January 2022.

An odd dissensus between confident metaphysicians and neopragmatist antimetaphysicians pervades early twenty-first century analytic philosophy. Each faction is convinced their side has won the day, but both are mistaken about the philosophical legacy of the twentieth century. More historical awareness is needed to overcome the current dissensus. Lewis and his possible-world system are lionised by metaphysicians; Quine’s pragmatist scruples about heavy-duty metaphysics inspire antimetaphysicians. But Lewis developed his system under the influence of his teacher Quine, inheriting from him his empiricism, (...) his physicalism, his metaontology, and, I will show in this paper, also his Humeanism. Using published as well as never-before-seen unpublished sources, I will make apparent that both heavy-duty metaphysicians and neopragmatist antimetaphysicians are wrong about the roles Quine and Lewis played in the development of twentieth-century philosophy. The two are much more alike than is commonly supposed, and Quine much more instrumental to the pedigree of current metaphysics. (shrink)

This is the revised version of an invited keynote lecture delivered at the "1st Australian Computing and Philosophy Conference". The paper is divided into two parts. The first part defends an informational approach to structural realism. It does so in three steps. First, it is shown that, within the debate about structural realism, epistemic and ontic structural realism are reconcilable. It follows that a version of OSR is defensible from a structuralist-friendly position. Second, it is argued that a version of (...) OSR is also plausible, because not all relata are logically prior to relations. Third, it is shown that a version of OSR is also applicable to both sub-observable and observable entities, by developing its ontology of structural objects in terms of informational objects. The outcome is informational structural realism, a version of OSR supporting the ontological commitment to a view of the world as the totality of informational objects dynamically interacting with each other. The paper has been discussed by several colleagues and, in the second half, ten objections that have been moved to the proposal are answered in order to clarify it further. (shrink)

Structural universals are a kind of complex universal. They have been put to work in a variety of philosophical theories but are plagued with problems concerning their compositional nature. In this article, we will discuss the following questions. What are structural universals? Why believe in them? Can we give a consistent account of their compositional nature? What are the costs of doing so?

Metaphysical grounding is often presented as a relation of directed dependence analogous to causation. The relationship between causation, properties, and laws of nature is hotly debated. I ask: what is the relationship between grounding, properties, and laws of metaphysics? I begin by considering the grounding analogue of Humean quidditism. Finding it implausible, I turn to the primitive-laws account of grounding, recently defended by Jonathan Schaffer and others. I argue this view is also unsatisfactory. I then present several possible dispositionalist-like accounts (...) and characterize the notion of a power to ground. I argue for three important conclusions: (i) each property essentially confers grounding powers; (ii) non-fundamental properties can be defined structurally in a particular sense, elucidating the claim that they are ‘nothing over and above’ the fundamental; and (iii) fundamental properties play a central role in grounding the grounding facts. Finally, it is significant that, combined with a causal powers-account of causal explanation, the door is open to a unified account of the metaphysics of causation and grounding: both flow from the natures of fundamental properties. (shrink)

This paper offers an original solution to the problem of the many, built on a foundation of powers-based causation. At its most basic, the solution should be understood as a type of maximality response, and on those grounds its originality might be questioned. However, it is argued that novelty of the solution owes as much to the meta-metaphysical context in which the solution is framed as it does the model of causal powers. A discussion of paradigms in metaphysics is included.

The paper argues for four claims: (1) The problem of mental causation and the argument for its solution in terms of the identity of mental with physical causes are independent of the theory of causation one favours. (2) If one considers our experience of agency as described by folk psychology to be veridical, one is committed to an anti-Humean metaphysics of causation in terms of powers that establish necessary connections. The same goes for functional properties in general. (3) A metaphysics (...) of causation in terms of powers is compatible with physics. (4) If combined with the argument for mental causes being identical with physical causes, that metaphysics leads to a conservative reductionism. (shrink)

This paper points out the merit of Nagelian reduction, namely to propose a model of inter-theoretic reduction that retains the scientific quality of the reduced theory and the merit of functional reduction, namely to take multiple realization into account and to offer reductive explanations. By considering Lewis and Kim’s proposal for local reductions, we establish that functional reduction fails to achieve a theory reduction and cannot retain the scientific quality of the reduced theory. We improve on that proposal by showing (...) how one can build functional sub-types that are coextensive with physical realizer types and thereby obtain a theory reduction that is explanatory and that vindicates the scientific quality of the special sciences. (shrink)

This paper argues that ontic structural realism (OSR) faces a dilemma: either it remains on the general level of realism with respect to the structure of a given theory, but then it is, like epistemic structural realism, only a partial realism; or it is a complete realism, but then it has to answer the question how the structure of a given theory is implemented, instantiated or realized and thus has to argue for a particular interpretation of the theory in question. (...) This claim is illustrated by examining how OSR fares with respect to the three main candidates for an ontology of quantum mechanics, namely many worlds-type interpretations, collapse-type interpretations and hidden variable-type interpretations. The result is that OSR as such is not sufficient to answer the question of what the world is like if quantum mechanics is correct. (shrink)

The paper sketches out an ontology of physics in terms of matter being primitive stuff distributed in space and all the properties physics is committed to being dispositions that fix the temporal development of the distribution of matter in space. Whereas such properties can be conceived as intrinsic properties of particles in classical mechanics, in quantum physics, there is a holistic property or structure that relates all matter and that fixes its temporal development.

In recent literature, it has become clear that quantum physics does not refute Humeanism: Lewis’s thesis of Humean supervenience can be literally true even in the light of quantum entanglement. This point has so far been made with respect to Bohm’s quantum theory. Against this background, this paper seeks to achieve the following four results: to generalize the option of quantum Humeanism from Bohmian mechanics to primitive ontology theories in general; to show that this option applies also to classical mechanics; (...) to establish that it requires a commitment to matter as primitive stuff, but no commitment to natural properties ; to point out that by removing the commitment to properties, the stock metaphysical objections against Humeanism from quidditism and humility no longer apply. In that way, quantum physics strengthens Humeanism instead of refuting it. (shrink)

Super-Humeanism is an even more parsimonious ontology than Lewisian standard Humean metaphysics in that it rejects intrinsic properties. There are point objects, but all there is to them are their relative positions and the change of them. Everything else supervenes on the Humean mosaic thus conceived. Hence, dynamical parameters come in on a par with the laws through their position in the best system. The paper sets out how Super-Humeanism has the conceptual means to reject van Inwagen’s consequence argument not (...) by taking the laws to depend on us, but by taking the initial values of the dynamical parameters that enter into the laws to be dependent on the motions that actually occur in the universe, including the motions of human bodies. The paper spells out the advantages of this proposal. (shrink)

Ontic structural realism is the view that structures are what is real in the first place in the domain of fundamental physics. The structures are usually conceived as including a primitive modality. However, it has not been spelled out as yet what exactly that modality amounts to. This paper proposes to fill this lacuna by arguing that the fundamental physical structures possess a causal essence, being powers. Applying the debate about causal vs categorical properties in analytic metaphysics to ontic structural (...) realism, I show that the standard argument against categorical and for causal properties holds for structures as well. Structural realism, as a position in the metaphysics of science that is a form of scientific realism, is committed to causal structures. The metaphysics of causal structures is supported by physics, and it can provide for a complete and coherent view of the world that includes all domains of empirical science. (shrink)

The paper argues in favour of a causal-functional theory of all properties including the physical ones and a conception of properties as tropes or modes in the sense of particular ways that objects are. It shows how these premises open up a version of functionalism according to which the properties on which the special sciences focus are identical with configurations of physical properties and thereby causally efficacious without there being any threat of eliminativism.

Recently the functional model of reduction has become something like the standard model of reduction in philosophy of mind. In this paper, I argue that the functional model fails as an account of reduction due to problems related to three key concepts: functionalization, realization and causation. I further argue that if we try to revise the model in order to make it more coherent and scientifically plausible, the result is merely a simplified version of what in philosophy of science is (...) known as mechanistic explanation. Hence, instead of analyzing reduction in philosophy of mind in terms of functional reduction, it should be analyzed in terms of mechanistic explanation. (shrink)

Two families of positions dominate debates over a metaphysically reductive analysis of knowledge. Traditionalism holds that knowledge has a complete, uniquely identifying analysis, while knowledge-first epistemology contends that knowledge is primitive—admitting of no reductive analysis whatsoever. Drawing on recent work in metaphysics, I argue that these alternatives fail to exhaust the available possibilities. Knowledge may have a merely partial analysis: a real definition that distinguishes it from some, but not all other things. I demonstrate that this position is attractive; it (...) evades concerns that its rivals face. (shrink)

The paper argues that a causal explanation of the correlated outcomes of EPR-type experiments is desirable and possible. It shows how Bohmian mechanics and the GRW mass density theory offer such an explanation in terms of a non-local common cause.

Is part of a perfectly natural, or fundamental, relation? Philosophers have been hesitant to take a stand on this issue. One reason for this hesitancy is the worry that, if parthood is perfectly natural, then the perfectly natural properties and relations are not suitably “independent” of one another. In this paper, I argue that parthood is a perfectly natural relation. In so doing, I argue that this “independence” worry is unfounded. I conclude by noting some consequences of the naturalness of (...) parthood. (shrink)

Suppose that one thinks that certain symmetries of a theory reveal “surplus structure”. What would a formalism without that surplus structure look like? The conventional answer is that it would be a reduced theory: a theory which traffics only in structures invariant under the relevant symmetry. In this paper, I argue that there is a neglected alternative: one can work with a sophisticated version of the theory, in which the symmetries act as isomorphisms.

Aristotle is essentially human; that is, for all possible worlds metaphysically consistent with our own, if Aristotle exists, then he is human. This is a claim about the essential property of an object. The claim that objects have essential properties has been hotly disputed, but for present purposes, we can bracket that issue. In this essay, we are interested, rather, in the question of whether properties themselves have essential properties (or features) for their existence. We call those who suppose they (...) do “property essentialists”; those who do not, “property anti-essentialists,” or “quidditists.” We offer two complementary arguments. Our total argument is under-girded by two assumptions: transworld identity theory and “received view” counterfactual semantics, a la David Lewis. We then argue that, if one presumes that these are true, then one risks running headlong into paradox if one also accepts property anti-essentialism. That's the first argument. By contrast, if one accepts these same assumptions in conjunction with property essentialism, then the paradox is avoided. This is the second argument. We take it that our arguments work to show that, between property essentialism and quidditism, the property essentialist is on better footing. Plausibly, properties themselves do have essential properties for their existence. (shrink)

Non-naturalism is the view that normative properties are response-independent, irreducible to natural properties, and causally inefficacious. An underexplored question for non-naturalism concerns the metasemantics of normative terms. Ideally, the non-naturalist could remain ecumenical, but it appears they cannot. Call this challenge the metasemantic challenge. This chapter suggests that non-naturalists endorse an epistemic account of reference determination of the sort recently defended by Imogen Dickie, with some modifications. An important implication of this account is that, if correct, a fully fleshed out (...) moral epistemology will simultaneously rebut metasemantic objections to non-naturalism. Thus, both the metasemantic and the more widely discussed epistemological challenges in effect amount to one. Before setting out the positive view, the chapter considers why all of the traditional metasemantic theories cause trouble for the non-naturalist. This includes discussions of teleosemantics, conceptual role semantics, as well as Schroeter and Schroeter’s “connectedness” model. (shrink)

People engage in pure moral inquiry whenever they inquire into the moral features of some act, agent, or state of affairs without inquiring into the non-moral features of that act, agent, or state of affairs. This chapter argues that ordinary people act rationally when they engage in pure moral inquiry, and so any adequate view in metaethics ought to be able to explain this fact. The Puzzle of Pure Moral Motivation is how to provide such an explanation. This chapter argues (...) that each of the standard views in metaethics has trouble providing such an explanation. Discussion of why reveals that a metaethical view can provide such an explanation only if it meets two constraints: it allows ordinary moral inquirers to know the essences of moral properties, and the essence of each moral property makes it rational to care for its own sake whether that property is instantiated. (shrink)

Here is a puzzling phenomenon. Moral theories are typically thought to be necessary. If act utilitarianism is true, for example, then it is necessarily true. However, scientific theories are typically thought to be contingent. If quantum field theory is true, it’s not necessarily true — the world could have been Newtonian. My aim is to explore this discrepancy between domains. -/- In particular, I explore the role of what I call `internality’ intuitions in motivating necessitism about both moral and scientific (...) domains. In effect, these internality intuitions tell against the explanatory role of certain `external’ entities – like moral or scientific principles. I’ll suggest that perhaps these internality intuitions are more compelling in the moral case than the scientific case. If so, this would rationalize the combination of moral necessitism and scientific contingentism. (shrink)

This thesis explores attempts to characterise the structure of reality. Three notions stand out: Lewisian naturalness, Sider’s ‘structure’, and grounding, where the latter has become the most popular way to characterise the structure of reality in the contemporary literature. I argue that none of these notions, as they are currently understood, are suited for limning the metaphysical structure of reality. In the first part of the thesis I argue that, by the lights of the relevant theories, both naturalness and structure (...) fall short of the theoretical role carved out for those posits. In the second part of the thesis I present two challenges to the ‘orthodox’ conception of grounding. The first contests the standard assumption that grounding is asymmetric, both by citing what I take to be best described as symmetric instances of grounding, and by developing and arguing for a new theory of metaphysical structure – ‘metaphysical interdependence’ – which takes grounding to be nonsymmetric. The second challenge concerns the relationship between grounding and explanation, and leads to a dilemma for the grounding theorist. My proposed resolution to the dilemma is to adopt an antirealist approach to grounding, which I further motivate and develop in the final chapter. (shrink)

The notion of fundamentality, as it is used in metaphysics, aims to capture the idea that there is something basic or primitive in the world. This metaphysical notion is related to the vernacular use of “fundamental”, but philosophers have also put forward various technical definitions of the notion. Among the most influential of these is the definition of absolute fundamentality in terms of ontological independence or ungroundedness. Accordingly, the notion of fundamentality is often associated with these two other technical notions.

David Lewis is typically interpreted as a class nominalist. One consequence of class nominalism, which he embraced, is that the reduction of ordered pairs, triples, etc to unordered sets of sets is conventional. The reaction by his Australian counterparts D.M. Armstrong and Peter Forrest was that Lewis was not being ontologically serious. This chapter evaluates this debate over serious ontology. It is argued that in one sense Lewis is ontologically serious, but that his additional commitment to structuralism about classes should (...) push him to adopt a trope-theoretic account of naturalness, which opens up another way to respond to the charge of not doing serious ontology. This conclusion is supported by certain remarks he makes in his correspondence, thus revealing how his thinking about properties appears to have evolved from property-egalitarianism to a sparse theory of tropes. (shrink)

The Humility Thesis is a persistent thesis in contemporary metaphysics. It is known by a variety of names, including, but not limited to, Humility, Intrinsic Humility, Kantian Humility, Kantian Physicalism, Intrinsic Ignorance, Categorical Ignorance, Irremediable Ignorance, and Noumenalism. According to the thesis, we human beings, and any knowers that share our general ways of knowing, are irremediably ignorant of a certain class of properties that are intrinsic to material entities … Continue reading Humility Regarding Intrinsic Properties →.

The perfectly natural properties and relations are special—they are all and only those that "carve nature at its joints." They act as reference magnets, form a minimal supervenience base, figure in fundamental physics and in the laws of nature, and never divide duplicates within or between worlds. If the perfectly natural properties are the (metaphysically) important ones, we should expect being a perfectly natural property to itself be one of the (perfectly) natural properties. This paper argues that being a perfectly (...) natural property is not a very natural property, and examines the consequences. (shrink)

2020 update of the entry "Properties".

Metaphysical orthodoxy holds that a privileged minority of properties carve reality at its joints. These are the so-called fundamental properties. This thesis concerns the contemporary philosophical debate about the nature of fundamental properties. In particular, it aims to answer two questions: What is the most adequate conception of fundamental properties? What is the “big picture” world-view that emerges by adopting such a conception? I argue that a satisfactory answer to both questions requires us to embrace a novel conception of powerful (...) qualities, according to which properties are at once dispositional and qualitative. By adopting the proposed conception of powerful qualities, an original theory of fundamental properties comes to light. I call it Dual-Aspect Account. In this thesis, I defend the Dual-Aspect Account and its superiority with respect to rival views of fundamental properties. I illustrate this claim by examining Dispositionalism, the view defended among others by Alexander Bird and Stephen Mumford, Categoricalism, which has been advocated notably by David Lewis and David Armstrong, and the Identity Theory of powerful qualities, primarily championed by C. B. Martin and John Heil. The latter is the standard conception of powerful qualities. However, in the literature, the Identity Theory faces the charge of contradiction. A preliminary task is therefore to show that a conception of powerful qualities is coherent. To accomplish this aim, I introduce the notion of an aspect of a property. On this interpretation, powerful qualities can be thought of as having dispositional and qualitative aspects. I show that such a conception allows us to disambiguate the claim that a property’s dispositionality is identical with its qualitativity, and evade the charge of contradiction. Aspects bring us other theoretical benefits. I illustrate this claim by showing how the Dual-Aspect Account offers us a promising theory of resemblance. I then compare its merits with David Armstrong’s theory of partial identity. The conclusion of this thesis is that the Dual-Aspect Account is better suited to capturing the world as we find it in everyday life and scientific investigation as compared to the theoretical positions examined. (shrink)

The glass vase on my desk is fragile. It should be handled with care because it it is likely to shatter or crack if it is knocked, dropped, or otherwise treated roughly. The vase has certain dispositions, for example the disposition to shatter when dropped. But what is this disposition? It seems on the one hand to be a perfectly real property, a genuine respect of similarity common to glass vases, china cups, ancient manuscripts, and anything else fragile. Yet on (...) the other hand my vase's disposition seems mysterious, "ethereal" (as Nelson Goodman (1954) put it) in a way that, say, its size and shape properties are not. For my vase's disposition, it seems, has to do only with its possibly shattering in certain conditions, conditions which I hope will never be realized. In general, it seems that nothing about the actual behavior of an object is ever necessary for it to have the dispositions it has. Many objects differ from each other with respect to their dispositions in virtue of their merely possible behavior, and this is a mysterious way for objects to differ. (shrink)

“There are no gaps in logical space,” David Lewis writes, giving voice to sentiment shared by many philosophers. But different natural ways of trying to make this sentiment precise turn out to conflict with one another. One is a *pattern* idea: “Any pattern of instantiation is metaphysically possible.” Another is a *cut and paste* idea: “For any objects in any worlds, there exists a world that contains any number of duplicates of all of those objects.” We use resources from model (...) theory to show the inconsistency of certain packages of combinatorial principles and the consistency of others. (shrink)