Barbara Vetter

Abilities, in contrast to mere dispositions, propensities, or tendencies, abilities seem to be features of agents that put the agent herself in control. But what is the distinguishing feature of abilities vis‐à‐vis other kinds of powers? Our aim in this paper is to point, in answer to this question, to a crucial feature of abilities that existing accounts have tended to neglect: their adaptivity. Adaptivity is a feature of how abilities are exercised. The main reason for its relative neglect has been that most extant accounts have focused solely on whether abilities are exercised successfully in certain possible situations and have mostly understood the exercise of an ability in terms of complete successful performance. We begin by pointing out two aspects of abilities with regard to which current accounts seem (at best) incomplete: control and exercise. We then introduce adaptivity as we understand it, and end by putting it to work in developing a fuller understanding of abilities that does better than current accounts.

In this review of Ann Whittle's book, I take a closer look at, and raise some concerns about, two crucial steps in the argument of the book. First, I consider the ‘all-in can’, the sense of ‘can’ that is relevant for freedom, and argue that it sits uneasily with Whittle’s foundation in the semantics of agentive modals. Second, I take a closer look at the notion of ‘robust control’ and its role in Whittle's argument for contextualism about moral responsibility, and argue that Whittle’s own conception of control is in tension with her argument for contextualism about moral responsibility.

Modal dispositionalism is the view that possibilities are a matter of the dispositions of individual objects: it is possible that p if and only if something has a disposition for p to be the case. We raise a problem for modal dispositionalism: nothing within the theory rules out that there could be necessary, perfect masks, which make the manifestation of a disposition impossible. Unless such necessary perfect masks are ruled out, modal dispositionalism runs the risk of failing to provide a sufficient condition for possibility, and indeed of engendering contradictions. But to rule them out, modal dispositionalism would have to revise a crucial tenet of the view, its localism.

My aim in this paper is to sketch, with a broad brush and in bare outlines, an approach to modal epistemology that is characterized by three distinctive features. First, the approach is agency-based: it locates the roots of our modal thought and knowledge in our experience of our own agency. Second, the approach is ambitious in that it takes the experience of certain modal properties in agency to be the sole distinctive feature of specifically modal thought and knowledge; everything that we know about modality beyond the experience of agency is a matter of applying standard methods of inquiry such as deduction, induction and abductive methods for choosing between theories. Third, the account holds that modal thought and knowledge is, first and foremost, about modal properties that are sufficiently like those encountered in agency.

Inspired both by our ordinary understanding of the world and by reflection on science, anti-Humeanism is a growing trend in metaphysics. Anti-Humeans reject the Lewisian doctrine of Humean supervenience that the world is “just one little thing and then another”, and argue instead that dispositions, powers, or capacities provide connection and activity in nature. But how exactly are we to understand the shared commitment of this anti-Humean movement? I argue that this kind of anti-Humeanism, at its most general level, is to be understood neither as a view about ontology nor about fundamentality, but rather as a specific claim about what explains what.

According to essentialism, metaphysical modality is founded in the essences of things, where the essence of a thing is roughly akin to its real definition. According to potentialism (also known as dispositionalism), metaphysical modality is founded in the potentialities of things, where a potentiality is roughly the generalized notion of a disposition. Essentialism and potentialism have much in common, but little has been written about their relation to each other. The aim of this paper is to understand better the relations between essence and potentiality, on the one hand, and between essentialism and potentialism, on the other. It is argued, first, that essence and potentiality are not duals but interestingly linked by a weaker relation dubbed ‘semi-duality’; second, that given this weaker relation, essentialism and potentialism are not natural allies but rather natural competitors; and third, that the semi-duality of essence and potentiality allows the potentialist to respond to an important explanatory challenge by using essentialist resources without thereby committing to essentialism.

In this thesis, I develop a nonreductive and general conception of potentiality, and explore the prospects of a realist account of possibility based on this account of potentiality. Potentialities are properties of individual objects; they include dispositions such as fragility and abilities such as the ability to play the piano. Potentialities are individuated by their manifestation alone. In order to provide a unified account of potentialities, I argue in chapter 2 that dispositions, contrary to philosophical orthodoxy, are best understood in terms only of their manifestations (as disposi- tions to ...), rather than in terms of a stimulus and a manifestation condition (as dispositions to ... if ...). Chapter 3 provides some preliminary motivation for a nonreductive and gen- eral account of potentiality, and chapter 4 develops such an account. The guiding question is how far the notion of potentiality can be extended from the initial ex- amples of familiar dispositions and abilities, and it is argued that it can be extended very far. Various features of potentialities are explored, among them extrinsicality, iterations of potentiality, and the behaviour of potentiality with regard to logical equivalence. In chapter 5, the account is set to work in providing the outlines and a defense of a potentiality-based account of possibility. The basic idea of such an account is that it is possible that p just in case some thing has a potentiality for p. The account is defended against the objection that there may not be enough potential- ities to ground all the possibilities that there are. Finally, in chapter 6, a logic of potentiality is formulated and the logic of possibility derived from it, showing that the potentiality-based account of possibility is formally adequate: it provides pos- sibility with the formal features that modal logicians have studied. I conclude that the proposed account of possibility is a promising research programme.

Eine systematische Diskussion der Rolle von Dispositionen in den Wissenschaften, mit besonderer Berücksichtigung der folgenden Positionen: (GCP) Mumford, S./Anjum, R., 2011, Getting Causes from Powers, Oxford: Ox- ford University Press. (MP) Marmodoro, A. (Hrsg.), 2010, The Metaphysics of Powers, NY: Routledge. (DC) Handfield, T. (Hrsg.), 2009, Dispositions and Causes. Oxford: Oxford University Press. (DD) Damschen, G./Schnepf, R./Stüber, K.R. (Hrsg.), 2009, Debating Dispo- sitions – Issues in Metaphysics, Epistemology and Philosophy of Mind, Berlin/ NY: DeGruyter. (LDC) Manley, D./Wasserman, R., 2008,,On Linking Dispositions and Con- ditionals‘, Mind 117: 59–84. (NM) Bird, A., 2007, Nature’s Metaphysics: Laws and Properties, Oxford: Ox- ford University Press. (DCP) Kistler, M./Gnassounou, B. (Hrsg.), 2007, Dispositions and Causal Po- wers, NY: Routledge.

The standard Kratzerian analysis of modal auxiliaries, such as ‘may’ and ‘can’, takes them to be univocal and context-sensitive. Our first aim is to argue for an alternative view, on which such expressions are polysemous. Our second aim is to thereby shed light on the distinction between semantic context-sensitivity and polysemy. To achieve these aims, we examine the mechanisms of polysemy and context-sensitivity and provide criteria with which they can be held apart. We apply the criteria to modal auxiliaries and show that the default hypothesis should be that they are polysemous, and not merely context-sensitive. We then respond to arguments against modal ambiguity. Finally, we show why modal polysemy has significant philosophical implications.

Alexander Bird puts forward a modest version of anti-Humeanism about the non-fundamental, by providing an argument for the existence of a certain select class of non-fundamental but sparse dispositions: those that have an evolutionary function. I argue that his argument over-generates, so much so that the sparse–abundant distinction, and with it the tenet of his anti-Humean view, becomes obsolete. I suggest an alternative way of understanding anti-Humeanism in the non-fundamental realm, one which is not concerned with the existence of sparse properties but with explanatory relations.

Individual objects have potentials: paper has the potential to burn, an acorn has the potential to turn into a tree, some people have the potential to run a mile in less than four minutes. Barbara Vetter provides a systematic investigation into the metaphysics of such potentials, and an account of metaphysical modality based on them. -/- In contemporary philosophy, potentials have been recognized mostly in the form of so-called dispositions: solubility, fragility, and so on. Vetter takes dispositions as her starting point, but argues for and develops a more comprehensive conception of potentiality. She shows how, with this more comprehensive conception, an account of metaphysical modality can be given that meets three crucial requirements: Extensional correctness: providing the right truth-values for statements of possibility and necessity; formal adequacy: providing the right logic for metaphysical modality; and semantic utility: providing a semantics that links ordinary modal language to the metaphysics of modality. -/- The resulting view of modality is a version of dispositionalism about modality: it takes modality to be a matter of the dispositions of individual objects. This approach has a long philosophical tradition going back to Aristotle, but has been largely neglected in contemporary philosophy. In recent years, it has become a live option again due to the rise of anti-Humean, powers-based metaphysics. The aim of Potentiality is to develop the dispositionalist view in a way that takes account of contemporary developments in metaphysics, logic, and semantics

Williamsonian modal epistemology is characterized by two commitments: realism about modality, and anti-exceptionalism about our modal knowledge. Williamson’s own counterfactual-based modal epistemology is the best known implementation of WME, but not the only option that is available. I sketch and defend an alternative implementation which takes our knowledge of metaphysical modality to arise, not from knowledge of counterfactuals, but from our knowledge of ordinary possibility statements of the form ‘x can F’. I defend this view against a criticism indicated in Williamson’s own work, and argue that it is better connected to the semantics of modal language.

Manley and Wasserman (2008) have provided a convincing case against analyses of dispositions in terms of one conditional, and a very interesting positive proposal that links any disposition to a ‘suitable proportion’ of a particular set of precise conditionals. I focus on their positive proposal and ask just how precise those conditionals are to be. I argue that, contrary to what Manley and Wasserman imply in their paper, they must be maximally specific, describing in their antecedents complete centred worlds. This suggests a natural semantics for dispositional expressions, which I briefly explore to argue that it lacks uniformity. I end by suggesting a variation on Manley and Wasserman's view which would preserve uniformity, though at the cost of some new puzzling questions.

This paper explores the prospects for dispositional accounts of abilities. According to so-called new dispositionalists, an agent has the ability to Φ iff they have a disposition to Φ when trying to Φ. We show that the new dispositionalism is beset by some problems that also beset its predecessor, the conditional analysis of abilities, and bring up some further problems. We then turn to a different approach, which links abilities not to motivational states but to the notion of success, and consider ways of implementing that approach. Our results suggest that there are principled disanalogies between abilities and disposition which prevent any dispositional account of abilities from succeeding.

It is a familiar point that many ordinary dispositions are multi-track, that is, not fully and adequately characterisable by a single conditional. In this paper, I argue that both the extent and the implications of this point have been severely underestimated. First, I provide new arguments to show that every disposition whose stimulus condition is a determinable quantity must be infinitely multi-track. Secondly, I argue that this result should incline us to move away from the standard assumption that dispositions are in some way importantly linked to conditionals, as presupposed by the debate about various versions of the ‘conditional analysis’ of dispositions. I introduce an alternative conception of dispositionality, which is motivated by linguistic observations about dispositional adjectives and links dispositions to possibility instead of conditionals. I argue that, because of the multi-track nature of dispositions, the possibility-based conception of dispositions is to be preferred.

Dispositionalism about modality is the view that metaphysical modality is a matter of the dispositions possessed by actual objects. In a recent paper, David Yates has raised an important worry about the formal adequacy of dispositionalism. This paper responds to Yates’s worry by developing a reply that Yates discusses briefly but dismisses as ad hoc: an appeal to a ’plenitude of powers’ including such powers as the necessarily always manifested power for 2+2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$2+2$$\end{document} to be 4. I argue that the reply is not ad hoc at all, by defending the metaphysics of dispositions that should underly it. I then argue, first, that a proper understanding of dispositions’ degrees provides us with an argument for such necessarily always manifested dispositions; second, that all the natural attempts to block that argument can be resisted without being ad hoc; and third, that pragmatic considerations explain our intuitive resistance to the ascription of necessarily always manifested dispositions. Dispositionalism can be formally adequate after all.