Sonia Roca-Royes

The phenomenon of persistent disagreement is large, especially in areas, like philosophy, where knowledge is typically thought to be a priori. This phenomenon has been taken by some to threaten even the possibility of philosophical knowledge. This chapter opposes such a pessimistic diagnostic, but in a qualified manner. By first motivating a non-conformist position on the epistemic significance of disagreement, it defends the stance that knowledge is made no less possible by our awareness of the disagreements. And yet—the qualification goes—the disagreement makes us _blind_ to whether we know. The scope of this diagnosis needs to be properly measured, and this is done, in the second part of the chapter, by separation of cases.

This chapter is an exploration of the sort of epistemology available to explain our _de re_ modal knowledge about abstract entities. The thesis suggested—in a first approximation to the issue—is somewhat provocative: as modal epistemologists, we don’t have much work to do; instead, the work is down to ontologists. The chapter first motivates the thesis by relying on a conception of abstract objects that makes the thesis a rather plausible one. The chapter then goes on to consider some potential concerns and it concludes that, while their treatment imposes some refinements and qualifications, the thesis stands as it is.

It is highly intuitive that the material origins of artefacts are essential to them. This thesis is most intuitive in its flexible version: approximate match, not exact match, of anartefact’s material origins is what is essential to it.This chapter provides an in-depth exploration of the theoretical options that accommodate this flexible thesis. It considers whether there can be coincident entities of the same kind, and whether it is helpful to work with sufficiency properties in place of individual essences. But, it is argued, all of the ways of defending the flexible thesis fail. The chapter concludes in favour of the inflexible version of the thesis.

ABSTRACT The paper discusses Jessica Leech's Modal Transcendentalism. In particular, it engages critically with the claim that her Objective Necessity, of Kantian inspiration, in being the strictest real necessity, earns the title of Metaphysical Necessity. I argue that a Neo-Aristotelian Modality better deserves that title, but that this discussion is ultimately a distraction, with the danger of making us see these two modalities as competitors of one another. They are not, and the theoretical benefits afforded by endorsing them both are to be explored.

Modality is a vast phenomenon. In fact, it is arguably a plurality of phenomena. Within it, one type of modality warrants distinctive interest in philosophy and, in particular, in metaphysics. In view of this, this Element has a first part devoted to modality as a general phenomenon, where different types of modalities are distinguished, and where the question of unification is raised. Following this, the second part is focused on metaphysical modality: the type of modality that is of distinctive interest in metaphysics, and thus for the series of this Element. In this second part, the overarching question is about the source of metaphysical modality, and the discussion here informs back, and is informed by, the question of unification from the first part. This title is also available as open access on Cambridge Core.

This paper scrutinises the limits of a posteriori induction in acquiring modal knowledge. I focus on my similarity-based account (Roca-Royes [2017]); an inductive, non-rationalist epistemology of modality about concrete entities. Despite the explanatory merits of the account in relation to a vast range of modal claims, this inductive epistemology has been found incapable of yielding knowledge of a certain, other range of modal claims. Here, two notions of knowability are distinguished which reveal some of these limitations to be not only accidental to the method but also virtuous. Additionally, the scrutiny suggests a recipe for increasingly pushing back, as modal enquirers, some of these limits. Limits will irremediably remain. But, as modal epistemologists, it is to explain what lies beyond these irremediable limits (not within) that we should look somewhere else.

This paper is an exploration of the prospects of rationalist, concept-based epistemologies of modality as far as essentialist and de re modal claims are concerned. I grant certain explanatory power to such epistemologies but, primarily, I identify their limitations. I first explore them in view of the (possible) existence of general as well as of singular modally loaded concepts and find their explanatory scope severely limited. Inspired by the abstractionist's concept-and-entitlement based hybrid model, the paper then explores a similarly hybrid strategy. The outcome of this exploration is that, regardless of its explanatory scope, it would be a misnomer to describe such hybrid view as concept-based. The result generalizes.

In ‘A New Route to the Necessity of Origin’, Rohbraugh and deRosset offer an argument for the Necessity of Origin appealing neither to Suffciency of Origin nor to a branching-times model of necessity. What is doing the crucial work in their argument is instead the thesis they name ‘Locality of Prevention’. In this response, we object that their argument is question-begging by showing, first, that the locality of prevention thesis is not strong enough to satisfactorily derive from it the intended conclusion, and, second, that the argument is not sound unless the Necessity of Origin is operating as an implicit premiss.

Due to the influence of Nathan Salmon’s views, endorsement of the “flexibility of origins” thesis is often thought to carry a commitment to the denial of S4. This paper rejects the existence of this commitment and examines how Peacocke’s theory of the modal may accommodate flexibility of origins without denying S4. One of the essential features of Peacocke’s account is the identification of the Principles of Possibility, which include the Modal Extension Principle (MEP), and a set of Constitutive Principles. Regarding their modal status, Peacocke argues for the necessity of MEP, but leaves open the possibility that some of the Constitutive Principles be only contingently true. Here, I show that the contingency of the Constitutive Principles is inconsistent with the recursivity of MEP, and this makes the account validate S4. It is also shown that, compatibly with the necessity of the Constitutive Principles, the account can still accommodate intuitions about flexibility of origins. However, the account we end up with once those intuitions are consistently accommodated may not be satisfactory, and this opens up the debate about whether or not artefacts allow for some variation in their origins.

The paper sketches an epistemology of de re possibility centred on the notion of similarity. The proposal is, roughly, that we know about some entities’ unrealized possibilities by extrapolation from knowledge about some other, similar entities’ realized possibilities. The account is limited, among other things, in that it does not cover knowledge of de re necessities or essentialist knowledge, if we have it. But even if alternative epistemologies could explain that type of knowledge too, the current account is found to best explain the de re possibility knowledge, thereby resisting a potential charge of redundancy.

This paper is about the epistemic challenge for mind-independence approaches of modality. The challenge is to elucidate the possibility conditions for modal knowledge, and arises from acceptance of the following three premises: (a) We have modal knowledge (which, for a mind-independence theorist is knowledge of the extra-mental world); (b) Any knowledge of the extra-mental world is grounded on causal affection; and (c) Any knowledge grounded on causal affection cannot outrun knowledge of mere truths (as opposed to modal truths). Most attempts to solve the challenge (Peacocke’s, Yablo’s and Chalmers’ among them), try to do so by denying premise (b). Here, reasons are given to doubt about the adequacy of such a strategy, and it is suggested that a better way of solving the challenge is by qualifying the acceptance of (b) as well as by denying (c).

Pace Necessitism – roughly, the view that existence is not contingent – essential properties provide necessary conditions for the existence of objects. Sufficiency properties, by contrast, provide sufficient conditions, and individual essences provide necessary and sufficient conditions. This paper explains how these kinds of properties can be used to illuminate the ontological status of merely possible objects and to construct a respectable possibilist ontology. The paper also reviews two points of interaction between essentialism and modal logic. First, we will briefly see the challenge that arises against S4 from flexible essential properties; as well as the moves available to block it. After this, the emphasis is put on the Barcan Formula (BF), and on why it is problematic for essentialists. As we will see, Necessitism can accommodate both (BF) and essential properties. What necessitists cannot do at the same time is to continue to understanding essential properties as providing necessary conditions for the existence of individuals; against what might be for some a truism.

The paper compares the suitability of two different epistemologies of counterfactuals—(EC) and (W)—to elucidate modal knowledge. I argue that, while both of them explain the data on our knowledge of counterfactuals, only (W)—Williamson’s epistemology—is compatible with all counterpossibles being true. This is something on which Williamson’s counterfactual-based account of modal knowledge relies. A first problem is, therefore, that, in the absence of further, disambiguating data, Williamson’s choice of (W) is objectionably biased. A second, deeper problem is that (W) cannot satisfactorily elucidate modal knowledge. Third, from a naturalistic perspective, the nature of this second problem favours (EC) against (W).

Due to the influence of Nathan Salmon’s views, endorsement of the “flexibility of origins” thesis is often thought to carry a commitment to the denial of S4. This paper rejects the existence of this commitment and examines how Peacocke’s theory of the modal may accommodate flexibility of origins without denying S4. One of the essential features of Peacocke’s account is the identification of the Principles of Possibility, which include the Modal Extension Principle (MEP), and a set of Constitutive Principles. Regarding their modal status, Peacocke argues for the necessity of MEP, but leaves open the possibility that some of the Constitutive Principles be only contingently true. Here, I show that the contingency of the Constitutive Principles is inconsistent with the recursivity of MEP, and this makes the account validate S4. It is also shown that, compatibly with the necessity of the Constitutive Principles, the account can still accommodate intuitions about flexibility of origins. However, the account we end up with once those intuitions are consistently accommodated may not be satisfactory, and this opens up the debate about whether or not artefacts allow for some variation in their origins.

The paper focuses on the Epistemic Challenge for mind-independent accounts of modality. The challenge can be formulated as an inconsistency problem among three premises and, therefore, any strategy to meet the challenge will require the negation of (at least) one of its premises. The aim of the paper is not to offer a positive solution to the challenge, but rather to argue for the claim that to follow a hybrid strategy is probably the best way to meet it. With some qualifications, reasons are given as to why empiricism should be the way to meet the challenge as far as de re modality is concerned, whereas rationalism might be the correct way of addressing it for the case of de dicto modality.

This guide accompanies the following articles: Sonia Roca‐Royes, ‘Essentialism vis‐à‐vis Possibilia, Modal Logic, and Necessitism.’Philosophy Compass 6/1 (2011): 54–64. doi: 10.1111/j.1747‐9991.2010.00363.x. Sonia Roca‐Royes, ‘Essential Properties and Individual Essences.’Philosophy Compass 6/1 (2011): 65–77. doi: 10.1111/j.1747‐9991.2010.00364.x. Author’s Introduction Intuitively, George Clooney could lose a finger and he would still be him. Also intuitively, he could not lose his humanity without ceasing to be altogether. So while he could have one less finger, he could not be other than human. These intuitions suggest that there are two kinds of properties: on the one hand, there are essential properties and, on the other, there are accidental properties. Essentialism is the view that captures those intuitions and claims that some of an object’s properties are essential and some are accidental. Essential properties are often appealed to in metaphysical arguments. Consider the famous Goliath–Lumpl example. Goliath is a clay‐statue, and Lumpl is the piece of clay from which Goliath is made. Are Goliath and Lumpl the same entity, or are they distinct, despite coinciding in the same spatial region (at least for a period of time)? An argument in favour of their distinctness appeals to essential properties. Let s be Goliath’s shape. Lumpl’s current shape is therefore also s. It seems that Lumpl could lose its current shape and still exist. Yet, if Goliath – the statue – were melted, for instance, it would cease to exist. Behind this reasoning is the belief that having shape s is essential to Goliath but not to Lumpl. Goliath and Lumpl can therefore be distinguished by their essential properties. Consequently, and by Leibniz’s Indiscernibility of Identicals– according to which identicals cannot be distinguished – Goliath and Lumpl are distinct objects. The essentialist intuition appealed to in this argument is that shapes are essential to statues but not to pieces of clay. Of course, this particular argument – like any other – can be resisted. It is all the same a good illustration of how essentialism is put to work in metaphysics. A good understanding of the broad phenomenon of essentialism is therefore an unavoidable task, since the credit of a lot of metaphysical arguments partially depends on it. Although the topic has been studied for millenniums, the two papers that this guide accompanies are focused on contemporary issues in essentialism, and so will do this guide too. Author Recommends Fine, Kit. ‘Essence and Modality.’Philosophical Perspectives 8 (1994): 1–16. One of the most cited and influential papers against the modal account of the notion of essence and in favour of what has subsequently been referred to in the literature as ‘the Finean account of the notion of essence’. Forbes, Graeme. The Metaphysics of Modality. Oxford: Clarendon Press, 1985. A foundational work in modality and essentialism. The first two chapters provide a valuable introduction to propositional and first order modal logic. Chapters 5–8 constitute a comprehensive essentialist theory and contain some of the most cited arguments for individual essences. Kripke, Saul. Naming and Necessity, Cambridge, MA: Harvard UP, 1972/1980. Another foundational work. With this book – which is, among other things, a defence of a Direct Theory of Reference – Kripke rescues, after Quine’s powerful attacks against it, and using the semantic rigidity of proper names, (Aristotelian) essentialism. Mackie, Penelope. How Things Might Have Been: Individuals, Kinds and Essential Properties. Oxford: Clarendon Press, 2006. An extremely valuable recent contribution to the field. Here, Mackie defends that, although essentialism is a real phenomenon, there are much fewer essential properties than is standardly believed, and labels this view ‘Minimalist Essentialism’. Beyond the intrinsic interest of the defence of Minimalist Essentialism, the book is also highly recommended for its clear reconstructions – and discussions – of some of the most influential essentialist arguments. In addition, the book’s bibliography is very comprehensive and updated, and it might be a useful resource for students. Plantinga, Alvin. The Nature of Necessity. Oxford: OUP, 1974. Yet another foundational work. Here, Plantinga offers his essentialist theory which, like Forbes’, also incorporates individual essences although of a very different sort from Forbes’. Plantinga believes in purely non‐qualitative individual essences, whereas Forbes’ aims at purely qualitative ones. The book is also excellent to provide a solid background to those unfamiliar with the topic. Roca‐Royes. ‘Essentialism vis‐à‐vis Possibilia, Modal Logic and Necessitism.’Philosophy Compass, 6/1 (2011): 54–64, doi: 10.1111/j.1747‐9991.2010.00363.x. This is one of the two papers this guide accompanies. It contains a comparative examination of two opposed responses to the problem of possibilia. One solution crucially appeals to individual essences and another – compatible with them, but not dependent on them – makes existence a necessary‐whenever‐possible property. Salmon, Nathan. Reference and Essence. Princeton: Princeton UP, 1981. Against what Kripke’s Naming and Necessity might have induced us to believe, Salmon’s Reference and Essence argues that essentialism cannot be derived from the Direct Theory of Reference. Our commitments to essentialism should therefore come from somewhere else. It also contains one of the most cited and influential arguments against the transitivity of the accessibility relation between worlds, which relies on flexible essential properties. Online Materials The Stanford Encyclopedia of Philosophy publishes extremely valuable entries on a vast variety of topics which are conveniently updated and revised. On essentialism, the following are to be highlighted: Teresa Robertson, ‘Essential vs. Accidental Properties’: Takashi Yagisawa, ‘Possible Objects’: Penelope Mackie, ‘Transworld Identity’: PhilPapers is an interactive directory of online philosophical publications to which one can subscribe, and which allows authors to submit their latest work. One might find it useful to check this on a regular basis, since contents are constantly updated. The following link is to the site’s resources on essentialism:. Sample Syllabus Because the phenomenon of essentialism is very broad, one can design an entire course on it, thereby having enough time to see some of the issues in considerable depth. The sample syllabus suggested here is of one such course, focusing exclusively on contemporary issues in essentialism. Less deeply, the topic of essentialism can also be introduced in a general course on metaphysics or on modality. To this effect, focusing on some of the topics suggested in weeks 1–6 below would perhaps be more appropriate than focusing on the more complex issues suggested for weeks 7–10. Week 1. Introduction to Essentialism. Two Notions of Essential Property: The Modal Account and the Finean Account Fine, Kit. ‘Essence and Modality.’Philosophical Perspectives 8 (1994): 1–16. Robertson, Teresa. ‘Essential vs. Accidental Properties.’Stanford Encyclopedia of Philosphy (Fall 2008 Edition). Ed. Edward N. Zalta. URL:. Roca‐Royes, Sonia. ‘Essential Properties and Individual Essences.’Philosophy Compass, 6/1 (2011): 65–77. Sections 1–2. Week 2. Essentialist Principles, I: Three Arguments for the Essentiality of Origin Kripke, Saul. Naming and Necessity. Cambridge, MA: Harvard UP, 1972/1980. Lecture III. Mackie, Penelope. ‘Identity, Time and Necessity.’Proceedings for the Aristotelian Society 98 (1998): 59–78. Rohbraugh, Guy and deRosset, Louis. ‘A New Route to the Necessity of Origin.’Mind 133 (2004): 705–25. Week 3. Essentialist Principles, II: Essentiality of Kind Brody, Baruch. ‘Natural Kinds and Real Essences.’Journal of Philosophy 64 (1967): 431–46. Mackie, Penelope. How Things Might Have Been: Individuals, Kinds and Essential Properties. Oxford: Clarendon Press, 2006. Chapters 7 and 8. Wiggins, David. Sameness and Substance Renewed. Cambridge: Cambridge UP, 2001. Chapter 3. Week 4. Essentialist Principles, III: Natural Kind Essentialism Kripke, Saul. ‘Identity and Necessity.’Identity and Individuation, Ed. M. K. Munitz. New York: New York University Press, 1971. 135–64. Kripke, Saul. Naming and Necessity. Cambridge, MA: Harvard UP, 1972/1980. Lecture III. Putnam, Hilary. ‘The Meaning of “Meaning”.’Minnesota Studies in the Philosophy of Science 7 (1975): 215–71. Week 5. Sufficient‐for‐Existence Properties (and Cross‐World Identification Principles) Chisholm, Roderick. ‘Identity through Possible Worlds: Some Questions.’Noûs 1.1 (1967): 1–8. Mackie, Penelope. How Things Might Have Been: Individuals, Kinds and Essential Properties. Oxford: Clarendon Press, 2006. Chapter 3. Salmon, Nathan. Reference and Essence. Princeton: Princeton UP, 1981. Chapter 7. Week 6. Individual Essences Mackie, Penelope. ‘Transworld Identity.’The Stanford Encyclopedia of Philosophy (Fall 2008 Edition). Ed. Edward N. Zalta. URL:. Section 4. Roca‐Royes, Sonia. ‘Essential Properties and Individual Essences.’Philosophy Compass 6/1 (2011): 65–77. Sections 3–4. Week 7. Flexible Essential Properties and S4 Roca‐Royes, Sonia. ‘Essentialism vis‐à‐vis Possibilia, Modal Logic, and Necessitism.’Philosophy Compass 6/1 (2011): 54–64. Section 3. Salmon, Nathan. Reference and Essence. Princeton: Princeton UP, 1981. Appendix 1. Week 8. Individual Essences and Possibilia Peacocke, Christopher. ‘Principles for Possibilia.’Noûs 36.3 (2002): 486–508. Roca‐Royes, Sonia. ‘Essentialism vis‐à‐vis Possibilia, Modal Logic, and Necessitism.’Philosophy Compass 6/1 (2011): 54–64. Section 2. Week 9. Necessitism and Essentialism: A Third Notion of Essential Property Linsky, Bernard and Zalta, Edward. ‘In Defense of the Contingently Nonconcrete.’Philosophical Studies 84 (1996): 283–94. Roca‐Royes, Sonia. ‘Essentialism vis‐à‐vis Possibilia, Modal Logic, and Necessitism.’Philosophy Compass 6/1 (2011): 54–64. Section 5. Williamson, Timothy. ‘Bare Possibilia.’Erkenntnis 48 (1998): 257–73. Week 10. Essentialism and Modal Logic: The Barcan Formula Menzel, Christopher. ‘Actualism.’The Stanford Encyclopedia of Philosophy (Summer 2010 Edition). Ed. Edward N. Zalta. URL:. Section 2. Roca‐Royes, Sonia. ‘Essentialism vis‐à‐vis Possibilia, Modal Logic, and Necessitism.’Philosophy Compass 6/1 (2011): 54–64. Section 4. Focus Questions • There is a debate as to whether essential properties– as well as individual essences and sufficient‐for‐existence properties– should be specified in purely qualitative terms or whether, by contrast, non‐purely qualitative – or even purely non‐qualitative – specifications are allowed. What are the main arguments against the availability of purely qualitative specifications? • Flexible essential properties seem to be more plausible than non‐flexible ones. Yet, together with sufficient‐for‐existence properties, they imply flexible individual essences. How plausible are these? Should we revise our intuitions supporting flexible essential properties? • What are, ultimately, the ontological differences between a necessitist approach to possibilia and an individual‐essences‐based approach? • According to necessitism, essential properties do not impose necessary conditions for an object’s existence. Can the necessitist, nonetheless, capture this role of essential properties by saying that, when it comes to possibly concrete entities, essential properties provide necessary conditions for an object’s concreteness? Can they, on a similar vein, also offer sufficient‐for‐concreteness properties as a surrogate for the (non‐necessitist’s) sufficient‐for‐existence properties? • Even after the enormous amount of literature that essentialism has generated, we are far from reaching a general agreement as to which properties are essential and which are accidental. Should this be a reason to reflect, critically, on the methodology that is being used in the arguments for or against essential properties? Is reliance on intuitions inescapable?

According to Essentialism, an object’s properties divide into those that are essential and those that are accidental. While being human is commonly thought to be essential to Socrates, being a philosopher plausibly is not. We can motivate the distinction by appealing—as we just did—to examples. However, it is not obvious how best to characterize the notion of essential property, nor is it easy to give conclusive arguments for the essentiality of a given property. In this paper, I elaborate on these issues and explore the way in which essential properties behave in relation to other related properties, like sufficient-for-existence properties and individual essences.

The paper argues against Peacocke's moderate rationalism in modality. In the first part, I show, by identifying an argumentative gap in its epistemology, that Peacocke's account has not met the Integration Challenge. I then argue that we should modify the account's metaphysics of modal concepts in order to avoid implausible consequences with regards to their possession conditions. This modification generates no extra explanatory gap. Yet, once the minimal modification that avoids those implausible consequences is made, the resulting account cannot support Peacocke's moderate rationalism