Periodic Reporting for period 1 - POTandESS (Potentiality and Essence: An Integrated Actualist Theory of Metaphysical Modality)
Reporting period: 2023-09-01 to 2025-08-31
Summary of the context and overall objectives of the project
Can I get to the airport in time to catch my flight? Can we stop catastrophic climatic changes, or is this now impossible? Our lives are shaped by the answers we give to such modal questions––questions of possibility and necessity. Modality, such as necessity or possibility, is also pervasive in all areas of philosophical and scientific inquiry: our understanding of causation, laws of nature, as well as responsibility and agency crucially depend on our understanding of what must or might happen. And yet, the nature of possibility and necessity remains mysterious. In virtue of which facts are certain truths necessary, while others are merely possible or contingent?
The main aim of my project is to study the sources of modality –– that is, to answer the question "in virtue of what are some things possible, impossible, or necessary?" From the late '50s and '60s the study of modality has been shaped by the crucial achievements in formal logic, and in particular by the framework of possible worlds semantics developed by Ruth Barcan Marcus and Saul Kripke. Since then, metaphysical investigations concerning the nature and source of modality have focussed on the status of possible worlds. More recently, however, a new wave of theories of modality has come to the fore. These theories all eschew talk of possible worlds –– or, at least, do not think that the sources of modality are to be found in the goings-on at such mysterious entities. Rather, they attempt to locate the sources of possibility and necessity in actual, concrete phenomena. Two theories have generated particular interest in the few years: Dispositionalism and Essentialism.
The central idea of Dispositionalism is that the world is populated by irreducibly dispositional properties –– that is, properties like fragility or flammability, which alone determine the possible behaviours of their bearers –– and that these can directly explain what is possible and what is not; necessity is determined by the absence of the relevant potentialities or dispositions. It can be roughly stated as follows:
(D◇) ‘possibly p’ is true iff and because there is something that has a power to p.
On the other hand, the central idea of Essentialism is that entities have a nature –– that there are essential facts about them. These essential facts do, in turn, determine what is necessarily the case with regard to their bearers, and thus can directly explain what is necessary. Possibility is determined indirectly, as whatever is not ruled out by any essence. Roughly, it can be stated as follows:
(E◻) ‘necessarily p’ is true iff and because there is some entities xx in virtue of whose nature p is true.
Dispositionalism seems to be especially well equipped to explain the modal facts involving the dynamic evolutions of a system that essentialism struggles with—how an entity behaves—and what is possible for it
to do at a later stage in time: ‘is it possible, at t, to stop the uranium pile to chain react at t*?’, ‘could I have run for another mile before stopping?’, etc.
Essentialism, on the other hand, seems well suited to account for those modal facts that involve or are derived from an object’s belonging to a certain natural kind (it is in virtue of the fact that Socrates is essentially human that he is necessarily rational), the truths of logic and mathematics (it is in virtue of the nature of 2, 3, and addition that necessarily, 2+3=5), and in general facts involving timeless or synchronic relations of dependence. In short, Essentialism seems to be very apt at playing what Schrenk called the “bookkeeping” function.
Both theories are still relatively in their infancy, and their face a number of yet unsolved issues. But even less studied and understood is their mutual relation. Are these theories incompatible and rivals, or can they be co-exist? Can there be a hybrid theory which incorporates elements of both? These are the central themes of my project.
More specifically, I focus on three lines of inquiry:
1) Examine and evaluate each theory independently: consider its strengths and weaknesses as sole candidate for the source of modality. When confronted with problems or shortcomings of each theory, the question becomes: can they be fixed without the resources provided by the other theory?
2) Examine and evaluate the obstacles to their integration. The main main issue that stands in the way of such an integration was an argument, due to Vetter (2021), to the effect that while possibility and necessity are dual operators (they can be interdefined as follows: possibly p just is not necessarily not p), potentiality and essence seem to be, at best, semi-dual –– that is, essentially p entails not potentially not p, but not potentially not to p does not seem to entail essentially p. Conversely, potentially p entails not essentially not p, but not essentially not p does not seem to entail potentially, p. Vetter individuates three reasons to maintain that essence and potentiality are just semi-dual: their different relation to time, to objects, and to existence. I aim to examine these three cases closely, and see whether they can be dispelled.
The main aim of my project is to study the sources of modality –– that is, to answer the question "in virtue of what are some things possible, impossible, or necessary?" From the late '50s and '60s the study of modality has been shaped by the crucial achievements in formal logic, and in particular by the framework of possible worlds semantics developed by Ruth Barcan Marcus and Saul Kripke. Since then, metaphysical investigations concerning the nature and source of modality have focussed on the status of possible worlds. More recently, however, a new wave of theories of modality has come to the fore. These theories all eschew talk of possible worlds –– or, at least, do not think that the sources of modality are to be found in the goings-on at such mysterious entities. Rather, they attempt to locate the sources of possibility and necessity in actual, concrete phenomena. Two theories have generated particular interest in the few years: Dispositionalism and Essentialism.
The central idea of Dispositionalism is that the world is populated by irreducibly dispositional properties –– that is, properties like fragility or flammability, which alone determine the possible behaviours of their bearers –– and that these can directly explain what is possible and what is not; necessity is determined by the absence of the relevant potentialities or dispositions. It can be roughly stated as follows:
(D◇) ‘possibly p’ is true iff and because there is something that has a power to p.
On the other hand, the central idea of Essentialism is that entities have a nature –– that there are essential facts about them. These essential facts do, in turn, determine what is necessarily the case with regard to their bearers, and thus can directly explain what is necessary. Possibility is determined indirectly, as whatever is not ruled out by any essence. Roughly, it can be stated as follows:
(E◻) ‘necessarily p’ is true iff and because there is some entities xx in virtue of whose nature p is true.
Dispositionalism seems to be especially well equipped to explain the modal facts involving the dynamic evolutions of a system that essentialism struggles with—how an entity behaves—and what is possible for it
to do at a later stage in time: ‘is it possible, at t, to stop the uranium pile to chain react at t*?’, ‘could I have run for another mile before stopping?’, etc.
Essentialism, on the other hand, seems well suited to account for those modal facts that involve or are derived from an object’s belonging to a certain natural kind (it is in virtue of the fact that Socrates is essentially human that he is necessarily rational), the truths of logic and mathematics (it is in virtue of the nature of 2, 3, and addition that necessarily, 2+3=5), and in general facts involving timeless or synchronic relations of dependence. In short, Essentialism seems to be very apt at playing what Schrenk called the “bookkeeping” function.
Both theories are still relatively in their infancy, and their face a number of yet unsolved issues. But even less studied and understood is their mutual relation. Are these theories incompatible and rivals, or can they be co-exist? Can there be a hybrid theory which incorporates elements of both? These are the central themes of my project.
More specifically, I focus on three lines of inquiry:
1) Examine and evaluate each theory independently: consider its strengths and weaknesses as sole candidate for the source of modality. When confronted with problems or shortcomings of each theory, the question becomes: can they be fixed without the resources provided by the other theory?
2) Examine and evaluate the obstacles to their integration. The main main issue that stands in the way of such an integration was an argument, due to Vetter (2021), to the effect that while possibility and necessity are dual operators (they can be interdefined as follows: possibly p just is not necessarily not p), potentiality and essence seem to be, at best, semi-dual –– that is, essentially p entails not potentially not p, but not potentially not to p does not seem to entail essentially p. Conversely, potentially p entails not essentially not p, but not essentially not p does not seem to entail potentially, p. Vetter individuates three reasons to maintain that essence and potentiality are just semi-dual: their different relation to time, to objects, and to existence. I aim to examine these three cases closely, and see whether they can be dispelled.
Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far
The research activity consisted largely in armchiar, a priori reflection on the issues of the project, and writing of scientific papers, either individually or in collaboration with colleagues.
In my first year of fellowship, I focussed mostly on issues concerning Dispositionalism and Essentialism taken individually. In particular, I have focussed on two issues concerning Dispositionalism and one concerning Essentialism. For the former, I have worked on the nature and role of degrees of powers and their relationship with modality, and the paradox of Necessary Perfect Masks, which is currently the most serious difficulty of Dispositionalism. These two themes proved to be closely related: degrees of powers proved to be the central element to my proposed strategy to solve the paradox of necessary perfect masks. Finding a solution to the paradox is a crucial result for the project, as it established the viability of Dispositionalism as an individual theory –– removing its main problem.
With regard to Essentialism, I have focussed on the relationship between essence, dependence, and fundamentality. The main result has been establishing, against the common consensus, that essence and essential dependence are not linked with orderings of relative fundamentality, and are instead connected with an altogether different kind of metaphysical explanation. This is relevant to the project at large, since the entanglement of essence and fundamentality was threatening the viability of essentialism as a whole (if essence were fundamentality inducing, then fundamental entities could not have a non-trivial essence, which would have made them fairly unfit for the foundation of modality at large).
In my second year of fellowship, I focussed on issues concerning the relationship of powers and governing laws of nature in explaining natural modality, and on some of the key motivations for thinking that potentialities and essences are semi-dual (which is the main obstacle to their integration). In particular, I have focussed on their relationship with regard to the issue of merely possible existence, and their relationship with the metaphysics of time. The relationships of Dispositionalism and Essentialism with regard to time and possible non-existence are two of the three points of non-compatibility identified by Vetter (2021) between the two theories. I have examined more closely the relationship of the two theories with these issue: in particular, Dispositionalism's relationship with these was not very clear. With regard to non-existence, I have concluded that both Essentialism and Dispositionalism entail Necessitism, and are therefore perfectly compatibile.
I have worked quite a bit on the relationship between Dispositionalism and time, both in determining whether Dispositionalism entails a certain metaphysics of time, and what sort of features does a hybrid temporal + modal logic have in a dispositionalist framework. I am currently doing the same with regard to Essentialism.
This has not yet led to a complete removal of all the obstacles to their integration, but I think it allows us to take a considerable step forward.
During the fellowship, I have completed five scientific papers: three individually, and two co-authored. Two more are still in the works, with one being close to completion and to be submitted before the end of the fellowship. Two of these papers have been already been accepted for publication in prestigious peer-reviewed journals, while the others are in the reviewing process. The outputs are the following:
1) "The Intensity of Powers", forthcoming in the Australasian Journal of Philosophy. It tackles the issue of undestanding and modelling the degrees of dispositions and potentialities. I develop a new conception of the degree of powers, offer a formal model, and discuss its relationship with the previous minstream model of degrees of powers.
2) "A solution for the problem of Necessary Perfect Masks", forthcoming in the Oxford Studies in Metaphysics. It tackles the most significant problem for Dispositionalism, namely the paradox of Necessary Perfact Masks, which has so far not received any satisfactory solution. I offer a solution to the paradox which saves Dispositionalism from inconsistency, and expands its expressive powers, offering the foundations for an account of counterpossible conditionals.
3) "Essential Dependence is not fundamentality inducing", with Michael Wallner (Graz). Currently under reviw at Erkenntnis. It tackles the issue of the connection between essence, dependence, and fundamentality. We argue that essence does not generate a fundamentality ordering, and thus offers metaphysical explanations considerably different from grounding or building.
4) "Governing Laws and the Power to be Governed", forthocming in an volume on the metaphysics of science, published by Routledge, edited by V. Seifert, S. Psillos, and S. Ioannidis. It tackles the relationship between powers and laws of nature. In paticular, it responds to a paper by Ioannidis, Psillos, and Livanios (2020) advocating for a dualist model that integrates both governing laws and causal powers. It argues that such integration fails, and the prosects of any dualist model are grim.
5) "Powers in the Spotlight", with Lorenzo Azzano (Milan). Currently under review at Philosophical Quarterly. It tackles the relationship between Dispositionalism and the metaphysics of time. It argues that Dispositionalism is committed to Necessitism and Permanentism, and that the best temporal ontology for powers theorists who value dynamicity is the moving spotlight theory.
In my first year of fellowship, I focussed mostly on issues concerning Dispositionalism and Essentialism taken individually. In particular, I have focussed on two issues concerning Dispositionalism and one concerning Essentialism. For the former, I have worked on the nature and role of degrees of powers and their relationship with modality, and the paradox of Necessary Perfect Masks, which is currently the most serious difficulty of Dispositionalism. These two themes proved to be closely related: degrees of powers proved to be the central element to my proposed strategy to solve the paradox of necessary perfect masks. Finding a solution to the paradox is a crucial result for the project, as it established the viability of Dispositionalism as an individual theory –– removing its main problem.
With regard to Essentialism, I have focussed on the relationship between essence, dependence, and fundamentality. The main result has been establishing, against the common consensus, that essence and essential dependence are not linked with orderings of relative fundamentality, and are instead connected with an altogether different kind of metaphysical explanation. This is relevant to the project at large, since the entanglement of essence and fundamentality was threatening the viability of essentialism as a whole (if essence were fundamentality inducing, then fundamental entities could not have a non-trivial essence, which would have made them fairly unfit for the foundation of modality at large).
In my second year of fellowship, I focussed on issues concerning the relationship of powers and governing laws of nature in explaining natural modality, and on some of the key motivations for thinking that potentialities and essences are semi-dual (which is the main obstacle to their integration). In particular, I have focussed on their relationship with regard to the issue of merely possible existence, and their relationship with the metaphysics of time. The relationships of Dispositionalism and Essentialism with regard to time and possible non-existence are two of the three points of non-compatibility identified by Vetter (2021) between the two theories. I have examined more closely the relationship of the two theories with these issue: in particular, Dispositionalism's relationship with these was not very clear. With regard to non-existence, I have concluded that both Essentialism and Dispositionalism entail Necessitism, and are therefore perfectly compatibile.
I have worked quite a bit on the relationship between Dispositionalism and time, both in determining whether Dispositionalism entails a certain metaphysics of time, and what sort of features does a hybrid temporal + modal logic have in a dispositionalist framework. I am currently doing the same with regard to Essentialism.
This has not yet led to a complete removal of all the obstacles to their integration, but I think it allows us to take a considerable step forward.
During the fellowship, I have completed five scientific papers: three individually, and two co-authored. Two more are still in the works, with one being close to completion and to be submitted before the end of the fellowship. Two of these papers have been already been accepted for publication in prestigious peer-reviewed journals, while the others are in the reviewing process. The outputs are the following:
1) "The Intensity of Powers", forthcoming in the Australasian Journal of Philosophy. It tackles the issue of undestanding and modelling the degrees of dispositions and potentialities. I develop a new conception of the degree of powers, offer a formal model, and discuss its relationship with the previous minstream model of degrees of powers.
2) "A solution for the problem of Necessary Perfect Masks", forthcoming in the Oxford Studies in Metaphysics. It tackles the most significant problem for Dispositionalism, namely the paradox of Necessary Perfact Masks, which has so far not received any satisfactory solution. I offer a solution to the paradox which saves Dispositionalism from inconsistency, and expands its expressive powers, offering the foundations for an account of counterpossible conditionals.
3) "Essential Dependence is not fundamentality inducing", with Michael Wallner (Graz). Currently under reviw at Erkenntnis. It tackles the issue of the connection between essence, dependence, and fundamentality. We argue that essence does not generate a fundamentality ordering, and thus offers metaphysical explanations considerably different from grounding or building.
4) "Governing Laws and the Power to be Governed", forthocming in an volume on the metaphysics of science, published by Routledge, edited by V. Seifert, S. Psillos, and S. Ioannidis. It tackles the relationship between powers and laws of nature. In paticular, it responds to a paper by Ioannidis, Psillos, and Livanios (2020) advocating for a dualist model that integrates both governing laws and causal powers. It argues that such integration fails, and the prosects of any dualist model are grim.
5) "Powers in the Spotlight", with Lorenzo Azzano (Milan). Currently under review at Philosophical Quarterly. It tackles the relationship between Dispositionalism and the metaphysics of time. It argues that Dispositionalism is committed to Necessitism and Permanentism, and that the best temporal ontology for powers theorists who value dynamicity is the moving spotlight theory.
Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)
The main result of my project so far has been developing a solution to the main shortcoming of Dispositionalism, namely the paradox of Necessary Perfect Masks. The results are presnted in "A solution for the problem of Necessary Perfect Masks", forthcoming in the Oxford Studies in Metaphysics.
The paradox threatened the theory as a whole with inconsistency. If left unsolved, the only option would be to completely abandon dispositionalism (thereby also removing any reason to even attempt to produce a hybrid theory with Essentialism, unless Essentialism provided the means to eliminate the inconsistency). I have developed a solution to the paradox using solely the resources available to the dispositionalist –– in particular, focussing on the role that degrees of powers play within Dispositionalism, and arguing for the existence of hitherto unrecognised or underappreciated instances of zero-degrees powers. If correct, this represents a considerable step forward for Dispositionalism, and strengthen its case as a self-standing candidate for a theory of modality. Showing the adequacy of Dispositionalism weakens the need for developing a hybrid theory.
The results of the paper have further applications. The main one is that it offers to the Dispositionalist an avenue to develop an (alethic) accunt of counter-possible conditionals, which was previosuly thought to be beyond reach (Vetter 2016). This would be a considerable result. I have not worked out all the details of such an account yet, but I think that the work on zero-degree powers lay a significant groundwork for future work on this. This will require further research.
Additionally, the notion of zero-degree powers seems to have found an application in the scholarship in the history of philosophy: it's being used in a book on Aristotle's philosophy of geometry that s being written by Chiara Martini (Cambridge), forthcoming for Oxford University Press, to account for how Aristotle could have accounted for some features of geometrical practice without invoking Platonic mathematical entities.
A second result has been developing a novel account of degrees of powers/dispositions, presented in "The Intensity of Powers", forthcoming in the Australasian Journal of Philosophy. Thus far, the only way in which dispositions were considered gradable concerned their modal strength –– very roughly, how likely they made their manifestations. These accounts, however, fail to do justice to other ways in which dispositions (and powers) can be compared and the role they play in our everyday and scientific reasoning. I have individuated a different kind of degrees for powers and dispositions and developed some models to capture the phenomenon. I have also sketched a discussion concerning their interaction. This interaction will require further research, and hopefully will generate a new and fruitful line of research in the metaphysics of dispositions.
A third result concerns essences and Essentialism. In collaboration with Michael Wallner (Graz), I believe I have established that essential dependence does not track or generates orderings of relative fundamentality. The paper is currently under review. The result would be significant for a variety of debates. First of all, it is the first paper that explicitly tackles the connection between essential dependence and fundamentality –– a link that has been often been assumed implicitly in the literature), and therefore hopefully will break ground for a future line of debate on this topic. If our results are correct, they would have significant consequences in a number of debates. First of all, they would strengthen the case for a form of pluralism about metaphysical explanation. Secondly, they would dissolve a number of objections moved to powers ontologies to the effect that fundamental properties must be categorical, thus influencing debates in metaphysics and metaphysics of science. Finally, it would affect discussions as to the relationship between grounding and essence (and attempts to analyse the one in terms of the other).
A fourth result concerns the relationship between potentialities, time, and existence. This is crucial for the project of integrating essentialism and dispositionalism, since the purportedly different relations with time, objects, and existence represented Vetter's (2021) main reasons for maintaining that essence and potentiality are just semi-dual. In joint work with Lorenzo Azzano (Milan) and Donatella Donati (L'Aquila) I have explored the under-investigated relationship of powers and time. In a paper with Donati (Dated Truths Without Dated Powers, Erkenntnis) I have argued that manifestations of powers should not embed temporal operators, and offered a model for how powers can make true statements that contain them. More recently, I have been working with Azzano on the consequence that this would have for the temporal+modal logic of dispositionalism. This is still work in progress, but the preliminary results are that it would force Dispositionalism to subscribe to two contentious theses, namely Perpetuity (necessarily p entails always p) and Plenitude (possibly p entails sometimes p). This would be a significant result, because it would considerably distinguish Dispositionalism from other theories of modality, including Essentialism. This requires further work: the relationship between time and modality from a new actualist perspective is severely under-studied. I am currently working on this topic.
Other work on the relationship between Dispositionalism and time, however, reveals that there are more points of contact and agreement between Dispositionalism and Essentialism with regard to time and existence. In joint work with Azzano (currently under review), we offer an argument that Dispositionalism entails Necessitism, the view that everything necessarily exists. In a recent paper Teitel (2019) has argued that also Essentialism is committed to necessitism (at least if it want to validate a logic as strong as S4 or S5). If both suggestions are right, this would be a significant result for the prospects of integrating Essentialism and Dispositionalism, since they end up agreeing on what was taken to be a crucial divergence between the two (existence and non-existence was taken to be one of the three reasons to hold the semi-duality of essence and potentiality.
In the same paper, we also offer a new, more pespicuous clarification of an internal debate within powers theorists, namely Activists and Passivists. We argue that the current state of the debate (e.g. Williams forthcoming) unduly ignores the relationship that these view have with the metaphysics of time. We then show, contra the common view in the literature, that who stress the 'dynamic nature of powers' should adopt a Moving Spotlight view of time, since we argue they are both committed robust temporal passage and permanentism. The marriage between Activist powers and Moving Spotlight Theory requires further investigation, and will hopefully open new avenues of research.
A fifth result concerns the interplay of powers and laws with regard to natural modality. In a forthcoming paper, "Governing Laws and the Power to be Governed", I show that a recent proposal by Ioannidis, Psillos, and Livanios to the effect that anti-Humeans explanations of natural modality require both governing laws and powers, is flawed and that any similar dualist accounts have poor prospects of working.
The paradox threatened the theory as a whole with inconsistency. If left unsolved, the only option would be to completely abandon dispositionalism (thereby also removing any reason to even attempt to produce a hybrid theory with Essentialism, unless Essentialism provided the means to eliminate the inconsistency). I have developed a solution to the paradox using solely the resources available to the dispositionalist –– in particular, focussing on the role that degrees of powers play within Dispositionalism, and arguing for the existence of hitherto unrecognised or underappreciated instances of zero-degrees powers. If correct, this represents a considerable step forward for Dispositionalism, and strengthen its case as a self-standing candidate for a theory of modality. Showing the adequacy of Dispositionalism weakens the need for developing a hybrid theory.
The results of the paper have further applications. The main one is that it offers to the Dispositionalist an avenue to develop an (alethic) accunt of counter-possible conditionals, which was previosuly thought to be beyond reach (Vetter 2016). This would be a considerable result. I have not worked out all the details of such an account yet, but I think that the work on zero-degree powers lay a significant groundwork for future work on this. This will require further research.
Additionally, the notion of zero-degree powers seems to have found an application in the scholarship in the history of philosophy: it's being used in a book on Aristotle's philosophy of geometry that s being written by Chiara Martini (Cambridge), forthcoming for Oxford University Press, to account for how Aristotle could have accounted for some features of geometrical practice without invoking Platonic mathematical entities.
A second result has been developing a novel account of degrees of powers/dispositions, presented in "The Intensity of Powers", forthcoming in the Australasian Journal of Philosophy. Thus far, the only way in which dispositions were considered gradable concerned their modal strength –– very roughly, how likely they made their manifestations. These accounts, however, fail to do justice to other ways in which dispositions (and powers) can be compared and the role they play in our everyday and scientific reasoning. I have individuated a different kind of degrees for powers and dispositions and developed some models to capture the phenomenon. I have also sketched a discussion concerning their interaction. This interaction will require further research, and hopefully will generate a new and fruitful line of research in the metaphysics of dispositions.
A third result concerns essences and Essentialism. In collaboration with Michael Wallner (Graz), I believe I have established that essential dependence does not track or generates orderings of relative fundamentality. The paper is currently under review. The result would be significant for a variety of debates. First of all, it is the first paper that explicitly tackles the connection between essential dependence and fundamentality –– a link that has been often been assumed implicitly in the literature), and therefore hopefully will break ground for a future line of debate on this topic. If our results are correct, they would have significant consequences in a number of debates. First of all, they would strengthen the case for a form of pluralism about metaphysical explanation. Secondly, they would dissolve a number of objections moved to powers ontologies to the effect that fundamental properties must be categorical, thus influencing debates in metaphysics and metaphysics of science. Finally, it would affect discussions as to the relationship between grounding and essence (and attempts to analyse the one in terms of the other).
A fourth result concerns the relationship between potentialities, time, and existence. This is crucial for the project of integrating essentialism and dispositionalism, since the purportedly different relations with time, objects, and existence represented Vetter's (2021) main reasons for maintaining that essence and potentiality are just semi-dual. In joint work with Lorenzo Azzano (Milan) and Donatella Donati (L'Aquila) I have explored the under-investigated relationship of powers and time. In a paper with Donati (Dated Truths Without Dated Powers, Erkenntnis) I have argued that manifestations of powers should not embed temporal operators, and offered a model for how powers can make true statements that contain them. More recently, I have been working with Azzano on the consequence that this would have for the temporal+modal logic of dispositionalism. This is still work in progress, but the preliminary results are that it would force Dispositionalism to subscribe to two contentious theses, namely Perpetuity (necessarily p entails always p) and Plenitude (possibly p entails sometimes p). This would be a significant result, because it would considerably distinguish Dispositionalism from other theories of modality, including Essentialism. This requires further work: the relationship between time and modality from a new actualist perspective is severely under-studied. I am currently working on this topic.
Other work on the relationship between Dispositionalism and time, however, reveals that there are more points of contact and agreement between Dispositionalism and Essentialism with regard to time and existence. In joint work with Azzano (currently under review), we offer an argument that Dispositionalism entails Necessitism, the view that everything necessarily exists. In a recent paper Teitel (2019) has argued that also Essentialism is committed to necessitism (at least if it want to validate a logic as strong as S4 or S5). If both suggestions are right, this would be a significant result for the prospects of integrating Essentialism and Dispositionalism, since they end up agreeing on what was taken to be a crucial divergence between the two (existence and non-existence was taken to be one of the three reasons to hold the semi-duality of essence and potentiality.
In the same paper, we also offer a new, more pespicuous clarification of an internal debate within powers theorists, namely Activists and Passivists. We argue that the current state of the debate (e.g. Williams forthcoming) unduly ignores the relationship that these view have with the metaphysics of time. We then show, contra the common view in the literature, that who stress the 'dynamic nature of powers' should adopt a Moving Spotlight view of time, since we argue they are both committed robust temporal passage and permanentism. The marriage between Activist powers and Moving Spotlight Theory requires further investigation, and will hopefully open new avenues of research.
A fifth result concerns the interplay of powers and laws with regard to natural modality. In a forthcoming paper, "Governing Laws and the Power to be Governed", I show that a recent proposal by Ioannidis, Psillos, and Livanios to the effect that anti-Humeans explanations of natural modality require both governing laws and powers, is flawed and that any similar dualist accounts have poor prospects of working.