This chapter contains sections titled: Introduction Two Interrelated Problems Lewis's Solution Inductive Paradox Identity versus Counterpart Theory Platonism: The Main Realist Alternative to Lewis An Aristotelian Alternative Leibniz's Account A Combined Account.

– The paper defends a naturalistic version of modal actualism according to which what is metaphysically possible is determined by dispositions found in the actual world. We argue that there is just one world—this one—and that all genuine possibilities are anchored by the dispositions exemplified in this world. This is the case regardless of whether or not those dispositions are manifested. As long as the possibility is one that would obtain were the relevant disposition manifested, it is a genuine possibility. (...) Furthermore, by starting from actual dispositional properties and branching out, we are able to include possibilities that are quite far removed from any state of affairs that happens to obtain, while still providing a natural and actual grounding of possibility. Stressing the importance of ontological considerations in any theory of possibility, it is argued that the account of possibility in terms of dispositional properties provides a more palatable ontology than those of its competitors. Coming at it from the other direction, the dispositional account of possibility also provides motivation for taking an ontology of dispositions more seriously. As well as the relevant dispositional notions required to lay out the view, the paper discusses the dispositional realism needed as the basis for the account of possibility. (shrink)

A striking feature of the traditional armchair method of philosophy is the use of imaginary examples: for instance, of Gettier cases as counterexamples to the justified true belief analysis of knowledge. The use of such examples is often thought to involve some sort of a priori rational intuition, which crude rationalists regard as a virtue and crude empiricists as a vice. It is argued here that, on the contrary, what is involved is simply an application of our general cognitive capacity (...) to handle counterfactual conditionals, which is not exclusively a priori and is not usefully conceived as a form of rational intuition. It is explained how questions of metaphysical possibility and necessity are equivalent to questions about counterfactuals, and the epistemology of the former (in particular, the role of conceiving or imagining) is a special case of the epistemology of the latter. A non-imaginary Gettier case is presented in order to show how little difference it makes. (shrink)

A striking feature of the traditional armchair method of philosophy is the use of imaginary examples: for instance, of Gettier cases as counterexamples to the justified true belief analysis of knowledge. The use of such examples is often thought to involve some sort of a priori rational intuition, which crude rationalists regard as a virtue and crude empiricists as a vice. It is argued here that, on the contrary, what is involved is simply an application of our general cognitive capacity (...) to handle counterfactual conditionals, which is not exclusively a priori and is not usefully conceived as a form of rational intuition. It is explained how questions of metaphysical possibility and necessity are equivalent to questions about counterfactuals, and the epistemology of the former (in particular, the role of conceiving or imagining) is a special case of the epistemology of the latter. A non-imaginary Gettier case is presented in order to show how little difference it makes. (shrink)

What are the most fundamental features of the world? Do minds stand outside the natural order? Is a unified picture of mental and physical reality possible? The Mind in Nature provides a staunchly realist account of the world as a unified system incorporating both the mental and the physical.

The Mind in Nature has two central aims. First, that of defending a ‘basic ontology’. Second, having advanced a plausible ontological framework, to appeal to it to cast light on the status of intentionality and the nature of consciousness, paying particular attention to the question of what distinguishes conscious systems from those that are vegetative.Central to Martin's basic ontology is his acceptance of a realist conception of dispositionality. Contrary to the view of David Lewis and others, talk about a thing's (...) dispositions cannot be analysed as talk about a thing's behaviour in a set of counterfactual circumstances. The account of dispositions that emerges from Martin's discussion is one according to which a specific disposition is either actual or it is not. To be actual a disposition need not be manifesting any manifestation. Unmanifesting dispositions are not, therefore, unactualized possibilia – a description which, he observes, is more fitting of unmanifested manifestations. In advancing a realist conception of dispositionality, Martin also opposes those who maintain that dispositional properties reduce to …. (shrink)

Possible worlds, concrete or abstract as you like, are irrelevant to the truthmakers for modality—or so I shall argue in this paper. First, I present the neo-Humean picture of modality, and explain why those who accept it deny a common sense view of modality. Second, I present what I take to be the most pressing objection to the neo-Humean account, one that, I argue, applies equally well to any theory that grounds modality in possible worlds. Third, I present an alternative, (...) properties-based theory of modality and explore several specific ways to flesh the general proposal out, including my favored version, the powers theory. And, fourth, I offer a powers semantics for counterfactuals that each version of the properties-based theory of modality can accept, mutatis mutandis. Together with a definition of possibility and necessity in terms of counterfactuals, the powers semantics of counterfactuals generates a semantics for modality that appeals to causal powers and not possible worlds. (shrink)

In this paper, I distinguish between two varieties of actualism—hardcore actualism and softcore actualism—and I critically discuss Ross Cameron’s recent arguments for preferring a softcore actualist account of the truthmakers for modal truths over hardcore actualist ones. In the process, I offer some arguments for preferring the hardcore actualist account of modal truthmakers over the softcore actualist one.