Giacomo Giannini

In this paper I argue that even the most radical metaphysics of powers (such as that adopted by Mumford & Anjum, Cartwright, or Groff) are compatible with eternalism. I first offer a taxonomy of powers ontologies, and attempt to characterise the difference between moderate and radical powers ontologies – the latter are characterised by an emphasis on production and dynamicity. I consider an argument by C. Friebe to the effect that the productive character of powers is inconsistent with Eternalism and find it wanting. I then elucidate the notion of dynamicity that radical powers theorists employ by making apparent their link with an ontology of irreducible processes. Finally, I respond to an argument by Donatella Donati to the effect that eternalism entails a reductive account of change which is inconsistent with process ontologies, and show that the the two are compatible. I conclude that we have no reason to think that radical powers metaphysics (and, a fortiori, every powers ontology) are not compatible with eternalism.

In this paper we examine whether and how powers ontologies can back formal causation. We attempt to answer three questions: i) what is formal causation; ii) whether we need formal causation, and iii) whether formal causation need powers and whether it can be grounded in powers. We take formal causal explanations to be explanations in which something's essence features prominently in the explanans. Three kinds of essential explanations are distinguished: constitutive, consequential, and those singling out something's propria. This last kind of explanation has been somewhat overlooked in the literature, but we argue that it features in much of the most relevant uses of formal explanations in philosophy and science. These are the explanations for why an object has certain propertis that are not, properly speaking, parts of its essence, but that belong to it more intimately than just being part of its consequential essence: they are the properties that ‘flow’ from something's essence. It is argued that a powers metaphysics is uniquely placed to make sense of this last phenomenon. We then distinguish three grades of involvement in which powers might be salient for formal causal explanations: i) powers might be the subject matter of the essence operator, ii) the essence of something might include (or be exhausted) by powers, or iii) powers can explain how propria can flow from something's constitutive existence.

Establishing Dispositionalism as a viable theory of modality requires the successful fulfilment of two tasks: showing that all modal truths can be derived from truths about actual powers, and offering a suitable metaphysics of powers. These two tasks are intertwined: difficulties in one can affect the chances of success in the other. In this paper, I generalise an objection to Dispositionalism by Jessica Leech and argue that the theory in its present form is ill-suited to account for de re truths about merely possible entities. I argue that such difficulty is rooted in a problem in the metaphysics of powers. In particular, I contend that the well-known tension between two key principle of powers ontology, namely Directedness and Independence has received an unsatisfactory solution so far, and that it is this unsatisfactory solution concerning the status of “unmanifested manifestations” that makes it hard for Dispositionalism to account for mere possibilia. I develop a novel account of the status of unmanifested manifestations and an overall metaphysics of powers which allows to better respond to Leech's objection and handle mere possibilia. The central idea of the proposal is that unmanifested manifestations are akin to mere logical existents, and are best characterised as non-essentially non-located entities.

Dispositionalism is the theory of modality that grounds all modal truths in powers: all metaphysically possible and necessary truths are to be explained by pointing to some actual power, or absence thereof. One of the main reasons to endorse dispositionalism is that it promises to deliver an especially desirable epistemology of modality. However, so far this issue has not be fully investigated with the care it is due. The aim of this paper is to fill this gap. We will cast some doubts on whether the dispositionalist really is in a better position to explain our modal knowledge. In fact, we argue that there is a tension between some core tenets of a powers metaphysics and the very features that make dispositionalism the ideal backdrop for a desirable epistemology of modality. We conclude that this leaves dispositionalists who want to deliver the promised epistemology with a hard, currently unfulfilled, task.

There is a tension between Dispositionalism––the view that all metaphysical modality is grounded in actual irreducible dispositional properties––and the possibility of time travel. This is due to the fact that Dispositionalism makes it much harder to solve a potentiality-based version of the grandfather paradox. We first present a potentiality-based version of the grandfather paradox, stating that the following theses are inconsistent: 1) time travel is possible, 2) powers fully ground modality, 3) self-defeating actions are impossible, 4) time-travellers retain their intrinsic powers upon time-travelling, and 5) time-travellers are ordinary agents with basic intrinsic potentialities. We then consider a number of potential solutions, and find them wanting. We argue that the metaphysical impossibility of performing a self-defeating action acts as a necessary perfect mask––while time-travel lets us “slip” the potentiality under the mask, thus generating the contradiction. We conclude considering what are the options for the dispositionalist.

Dispositionalism is the theory of modality according to which all (metaphysical and natural) modal truths are made true by some actual irreducibly dispositional property. The relationship between Dispositionalism and time is yet to be satisfactorily explored. In this paper we contribute to this task by examining how Dispositionalism deals with ‘dated truths’: propositions involving a specific time, e.g. “It might rain at 12.30”. We examine two possible accounts: the first, 'Dated Manifestations Strategy', is the idea that powers are very fine-grained, and tend towards temporally very specific manifestations. We argue that such strategy should not be adopted, for it leads to unnecessary violations of ontological parsimony; it is unable to accommodate an ontology of platonic universals; and it is incapable of offering a principled explanation of the forward-looking nature of powers. We offer an alternative account, the "Duration Strategy", which relies on an independently determined arrow of time and the existence of some “duration facts” that specify how long a power takes to bring about its manifestation. We argue that the Duration Strategy is to be preferred. We then flesh out the account by exploring the connection between powers, duration facts, and processes

In this dissertation, I develop a metaphysics of powers to ground Dispositionalism, the theory of the source of modality according to which all alethic modal truths are grounded in dispositional properties instantiated in the actual world. I consider a number of key theses that powers metaphysics display, and investigate which can be incorporated in the metaphysical base of Dispositionalism, and how. In the first part I examine the interaction of two core principles of powers ontologies: Directedness, the thesis that powers ‘point at’ their manifestations, and Independence, the thesis that powers can fail to manifest. These two principles are in tension: there is an argument, known as Too Much Possibility, to the effect that they are inconsistent. I examine various strategies to resist the argument. These involve Physical Intentionality, numerical identity between power and manifestation, process ontologies, and platonic universals. I conclude that they are all unsatisfactory. In the second part, I develop a ‘minimal metaphysics of powers’ that is immune from the threat of Too Much Possibility. This involves considering unmanifested manifestations to be akin to Mere Logical Existents. I argue that the best way to avoid the tension at the heart of powers ontologies is to conceive of unmanifested manifestations as non-essentially non-spatiotemporally located entities. I then consider some consequences of minimal metaphysics: I examine which ontological category the manifestations of power can belong to, and what are the prospects of grounding metaphysical, as opposed to natural, modality. Finally, in the third part, I investigate whether further key theses of powers ontologies can be incorporated into the minimal metaphysics. This leads to discuss the relationship of the minimal metaphysics with grounding and dependency relations, the metaphysics of time, the truthmaking principle, and tendential theories of powers.

Establishing Dispositionalism as a viable theory of modality requires the successful fulfilment of two tasks: (i) showing that all modal truths can be derived from truths about actual powers, and (ii) offering a suitable metaphysics of powers. These two tasks are intertwined: difficulties in one can affect the chances of success in the other. In this paper, I generalise an objection to Dispositionalism by Jessica Leech and argue that the theory in its present form is ill-suited to account for de re truths about merely possible entities. I argue that such difficulty is rooted in a problem in the metaphysics of powers. In particular, I contend that the well-known tension between two key principle of powers ontology, namely Directedness (all powers are “for” their manifestation) and Independence (some powers might fail to bring about their manifestation) has received an unsatisfactory solution so far, and that it is this unsatisfactory solution concerning the status of “unmanifested manifestations” that makes it hard for Dispositionalism to account for mere possibilia. I develop a novel account of the status of unmanifested manifestations and an overall metaphysics of powers which allows to better respond to Leech's objection and handle mere possibilia. The central idea of the proposal is that unmanifested manifestations are akin to mere logical existents, and are best characterised as non-essentially non-located entities.

In this paper I argue that even the most radical metaphysics of powers (such as that adopted by Mumford and Anjum, Cartwright, or Groff) are compatible with eternalism. I first offer a taxonomy of powers ontologies, and attempt to characterise the difference between moderate and radical powers ontologies—the latter are characterised by an emphasis on _production_ and _dynamicity_. I consider an argument by C. Friebe to the effect that the productive character of powers is inconsistent with Eternalism and find it wanting. I then elucidate the notion of _dynamicity_ that radical powers theorists employ by making apparent their link with an ontology of irreducible processes. Finally, I respond to an argument by Donatella Donati to the effect that eternalism entails a reductive account of change which is inconsistent with process ontologies, and show that the the two are compatible. I conclude that we have no reason to think that radical powers metaphysics (and, a fortiori, every powers ontology) are not compatible with eternalism.