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² Gibbard, ‘Contigent Identity’, 191.

³ According to Leibniz's Law, necessarily for all objects, x and y, if x and y are numerically identical (i.e. x=y), then x and y are qualitatively indiscernible (i.e. they have all the same properties and stand in all the same relations). Leibniz's Law should be distinguished from the much more controversial converse principle, the Identity of Indiscernibles, according to which necessarily for all objects, x and y, if x and y are qualitatively indiscernible (i.e. have all the same properties and stand in all the same relations), then x and y are numerically identical (i.e. x=y). For further discussion of the cogency of Leibniz's Law style arguments for the numerical distinctness of coincident objects, see Koslicki, Kathrin, ‘Almost Indiscernible Objects and the Suspect Strategy’, The Journal of Philosophy 102 (2005), 55–77CrossRefGoogle Scholar.

⁴ For illustrations along these lines, see for example Fine, Kit, ‘A Counter-example to Locke's Thesis’, The Monist 83 (2000), 357–361CrossRefGoogle Scholar.

⁵ Bennett, Karen, ‘Spatio-temporal Coincidence and the Grounding Problem’, Philosophical Studies 118 (2004), 341CrossRefGoogle Scholar.

⁶ Bennett, ‘Spatio-temporal Coincidence and the Grounding Problem’, 341–342.

⁷ For additional discussion of the Grounding Problem, see also deRosset, Louis, ‘What is the Grounding Problem?’, Philosophical Studies: An International Journal for Philosophy in the Analytic Tradition 156 (2011), 173–197CrossRefGoogle Scholar; Divers, John, ‘Coincidence and Form’, Proceedings of the Aristotelian Society, Supplementary Volume 82 (2008), 119–137CrossRefGoogle Scholar; Fine, Kit, ‘Coincidence and Form’, Proceedings of the Aristotelian Society, Supplementary Volume 82 (2008), 101–118CrossRefGoogle Scholar; Jago, Mark, ‘Essence and the Grounding Problem’, in Reality Making (ed.) Jago, Mark (Oxford: Oxford University Press, 2016), 99–120CrossRefGoogle Scholar; Olson, Eric, ‘Material Coincidence and the Indiscernibility Problem’, The Philosophical Quarterly 51 (2001), 337–355CrossRefGoogle Scholar; Sutton, C. S., ‘Colocated Objects, Tally-Ho: A Solution to the Grounding Problem’, Mind 121 (2012), 703–730CrossRefGoogle Scholar; Zimmerman, Dean, ‘Theories of Masses’, Philosophical Review 104 (1995), 53–110CrossRefGoogle Scholar.

⁸ ‘Spatio-temporal Coincidence and the Grounding Problem’, 343–344.

⁹ See for example Baker, Lynne Rudder, Persons and Bodies: A Constitution View (New York: Cambridge University Press, 2000)CrossRefGoogle Scholar; Rea, Michael, ‘Supervenience and Colocation’, American Philosophical Quarterly 34 (1997), 367–375Google Scholar; Sider, Theodore, ‘Global Supervenience and Identity Across Times and Worlds’, Philosophy and Phenomenological Research 59 (1999), 913–937CrossRefGoogle Scholar; Dean Zimmerman, ‘Theories of Masses’.

¹⁰ See for example Sidelle, Alan, Necessity, Essence, and Individuation: A Defense of Conventionalism (Ithaca: Cornell University Press, 1989)Google Scholar; ‘Rigidity, Ontology, and Semantic Structure’, The Journal of Philosophy 89 (1992), 410–430CrossRefGoogle Scholar.

¹¹ Bennett, ‘Spatio-temporal Coincidence and the Grounding Problem’, 354. See also Yablo, Stephen, ‘Identity, Essence, and Indiscemibility’, The Journal of Philosophy 84 (1987), 293–314CrossRefGoogle Scholar, and ‘Mental Causation’, The Philosophical Review 101 (1992), 245–280CrossRefGoogle Scholar, though Yablo's motivation for endorsing the plenitude principle is not driven by the desire to provide a response to the Grounding Problem.

¹² See Koslicki, Kathrin, The Structure of Objects (Oxford: Oxford University Press, 2008)CrossRefGoogle Scholar; Form, Matter, Substance (Oxford: Oxford University Press, 2018)Google Scholar.

¹³ For other defenses of a hylomorphic ontology, see for example Brower, Jeffrey, Aquinas's Ontology of the Material World: Change, Hylomorphism, and Material Objects (Oxford: Oxford University Press, 2014)CrossRefGoogle Scholar; Evnine, Simon, Making Objects and Events: A Hylomorphic Theory of Artifacts, Actions, and Organisms (Oxford: Oxford University Press, 2016)CrossRefGoogle Scholar; Fine, Kit, ‘Acts, Events and Things’, Language and Ontology, Proceedings of the 6^th International Wittgenstein Symposium (1982), 97–105Google Scholar; Fine, Kit, ‘Things and Their Parts’, Midwest Studies in Philosophy 23 (1999), 61–74CrossRefGoogle Scholar; Harte, Verity, Plato on Parts and Wholes: The Metaphysics of Structure (Oxford: Clarendon Press, 2002)CrossRefGoogle Scholar; Jaworski, William, Structure and the Metaphysics of Mind: How Hylomorphism Solves the Mind-Body Problem (New York: Oxford University Press, 2016)CrossRefGoogle Scholar; Johnston, Mark, ‘Parts and Principles: False Axioms in Mereology’, Philosophical Topics 30 (2002), 129–166CrossRefGoogle Scholar; Johnston, Mark, ‘Hylomorphism’, The Journal of Philosophy 103 (2006), 652–698CrossRefGoogle Scholar; Koons, Robert, ‘Staunch vs. Faint-Hearted Hylomorphism: Toward an Aristotelian Account of Composition’, Res Philosophica 91 (2014), 151–177CrossRefGoogle Scholar; Lowe, E.J., ‘Form Without Matter’, in Form and Matter: Themes in Contemporary Metaphysics (ed.) Oderberg, David (Oxford: Blackwell, 1999), 1–21Google Scholar; Marmodoro, Anna, ‘Aristotle's Hylomorphism Without Reconditioning’, Philosophical Inquiry 36 (2013), 5–22CrossRefGoogle Scholar; Novotný, Daniel D. and Novák, Lukáš (eds), Neo-Aristotelian Perspectives in Metaphysics (New York: Routledge, 2014)Google Scholar; Oderberg, David, Real Essentialism (New York: Routledge Taylor & Francis, 2007)CrossRefGoogle Scholar; Peramatzis, Michail, Priority in Aristotle's Metaphysics (New York: Oxford University Press, 2011)CrossRefGoogle Scholar; Rea, Michael, ‘Hylomorphism Reconditioned’, Philosophical Perspectives 25 (2011), 341–358CrossRefGoogle Scholar; Sattig, Thomas, The Double Lives of Objects (Oxford: Oxford University Press, 2015)CrossRefGoogle Scholar; Stump, Eleonore, ‘Non-Cartesian Substance Dualism and Materialism Without Reductionism’, Faith and Philosophy 12 (1995), 505–531CrossRefGoogle Scholar; Stump, Eleonore, ‘Emergence, Causal Powers, and Aristotelianism in Metaphysics’, in Powers and Capacities in Philosophy: The New Aristotelianism (eds) Groff, Ruth and Greco, John (New York: Routledge, 2013), 48–68Google Scholar; Toner, Patrick, ‘On Hylemorphism and Personal Identity’, European Journal of Philosophy 19 (2011), 454–473Google Scholar; Toner, Patrick, ‘Hylemorphic Animalism’, Philosophical Studies 155 (2011), 65–81CrossRefGoogle Scholar.

¹⁴ Sidelle, Alan, ‘Does Hylomorphism Offer a Distinctive Solution to the Grounding Problem?’, Analysis 74 (2014), 397–404CrossRefGoogle Scholar.

¹⁵ ‘Does Hylomorphism Offer a Distinctive Solution to the Grounding Problem?’, 402.

¹⁶ I myself am guilty of Sidelle's charge that hylomorphists engage in false advertising when they claim that their account generates a distinctively hylomorphic solution to the Grounding Problem. I argued in The Structure of Objects (181ff) that a mere difference in formal parts between numerically distinct spatiotemporally coincident objects is sufficient to yield a distinctively hylomorphic solution to the Grounding Problem. I no longer hold this position. Instead, as I propose below, in addition to the independently motivated essential differences between coincident objects, I now believe that a non-modal conception of essence is also needed to formulate a credible response to the Grounding Problem. But hylomorphists and non-hylomorphists alike can help themselves to this strategy; hence, the resulting response to the Grounding Problem is not distinctively hylomorphic. As long as hylomorphists are careful not to engage in false advertising, however, they should not be concerned if the main features of their response to the Grounding Problem can be replicated by non-hylomorphists as well.

¹⁷ Although this particular case happens to involve artifacts, I assume that a case in which a concrete particular object and its matter are spatiotemporally coincident could, in principle, be constructed for living or non-living members of natural kinds as well. I thus intend my reasoning in what follows to be completely general and not to turn on any characteristics that might be specific to the case of artifacts.

¹⁸ The representation in (1) is an oversimplification, since it ignores the possibility that O can persist through changes with respect to its matter over time. Thus, a more realistic representation of the claim that Goliath is a compound of some matter, m, and a form, f, would have to accommodate such possibilities as the following: Goliath exists at a time, t_1, and at a distinct time, t₂, and the matter, m₁, which composes Goliath at t₁ is distinct from the matter, m₂, which composes Goliath at t₂. For the sake of simplicity, I will in what follows continue to surpress the necessary relativization to time.

¹⁹ Within each of these camps, further choices are available depending on the more specific ontological category to which forms are assigned (see Koslicki, Form, Matter, Substance, Section III.2, for more detail). To illustrate, universal forms theorists have for example assigned forms to the following ontological categories (where the members of these ontological categories are of course, in each case, construed as universals): properties (e.g. Peramatzis, Priority in Aristotle's Metaphysics); relations (e.g. Johnston, ‘Hylomorphism’); powers (e.g. Marmodoro, ‘Aristotle's Hylomorphism Without Reconditioning’); or activities (e.g. Kosman, Aryeh, The Activity of Being (Cambridge: Harvard University Press, 2013CrossRefGoogle Scholar). Individual forms theorists, similarly, have a range of options available to them, depending on whether they take forms to be objects (e.g. Lowe, ‘Form Without Matter’); properties, construed as particulars (e.g. Brower, Aquinas's Ontology of the Material World: Change, Hylomorphism, and Material Objects); states (e.g. Stump, ‘Non-Cartesian Substance Dualism and Materialism Without Reductionism’); functions (e.g. Kit Fine, ‘Things and Their Parts’); powers, construed as particulars (e.g. Jaworski, Structure and the Metaphysics of Mind: How Hylomorphism Solves the Mind-Body Problem); activities or processes, construed as particulars (e.g. Koons, ‘Staunch vs. Faint-Hearted Hylomorphism: Toward an Aristotelian Account of Composition’); facts (e.g. Sattig, The Double Lives of Objects); or actions (e.g. Evnine, Making Objects and Events: A Hylomorphic Theory of Artifacts, Actions, and Organisms). In addition, if forms turn out not to fit into any previously recognized category, both universal and individual forms theorists (as well as the hybrid theorists I am about to mention) also have the option of designating forms as sui generis entities.

²⁰ The hybrid position can be found for example in Alan Code, ‘The Aporematic Approach to Primary Being in Metaphysics Z’, in New Essays on Aristotle, Canadian Journal of Philosophy, Supplementary Volume X (1984) (eds) Francis Jeffry Pelletier and John King-Farlow, 1–20; Gill, Mary Louise, Aristotle on Substance: The Paradox of Unity (Princeton: Princeton University Press, 1989)Google Scholar; and Rea, ‘Hylomorphism Reconditioned’.

²¹ Since my own sympathies lie with the individual forms hypothesis, I will in what follows assume that forms are to be treated as particular or individual entities of some sort. Due to space constraints, I am unfortunately unable to justify this very controversial assumption in the present context. For a detailed discussion, see my Form, Matter, Substance, Section III.4.3; and ‘Essence and Identity’, forthcoming in Metaphysics, Meaning and Modality: Themes from Kit Fine (ed.) Mircea Dumitru (Oxford: Oxford University Press).

²² The term, ‘figure’, is intentionally vague to allow for different ways of filling in the relation between form and essence. Proponents of the individual and universal forms hypothesis alike have the option of holding either that the essence of a matter-form compound is exhausted by (i.e. identical to) its form or that the essence of a matter-form compound includes but is not exhausted by its form, e.g. on the grounds that the matter composing the compound also in some way figures in its essence, if only generically (Koslicki, Form, Matter, Substance, Section III.4.2.). Either way a statement of the essence of a matter-form compound will include a reference to its form.

²³ Some hylomorphists have tried to approach the relation between a matter-form compound and its matter by distinguishing a notion of numerical sameness that is not to be confused with the relation of numerical identity; see for example Rea, Michael, ‘Sameness Without Identity: An Aristotelian Solution to the Problem of Material Constitution’, Ratio 11 (1998), 316–328CrossRefGoogle Scholar.

²⁴ Marmodoro, ‘Aristotle's Hylomorphism Without Reconditioning’.

²⁵ Versions of hylomorphic monism can also be found for example in Brower, Aquinas's Ontology of the Material World: Change, Hylomorphism, and Material Objects; Jaworski, Structure and the Metaphysics of Mind: How Hylomorphism Solves the Mind-Body Problem; Oderberg, Real Essentialism; Michael Rea, ‘Sameness Without Identity: An Aristotelian Solution to the Problem of Material Constitution’; and Toner, Patrick, ‘Emergent Substance’, Philosophical Studies 141 (2008), 281–297CrossRefGoogle Scholar.

²⁶ Sidelle quite clearly construes non-robust hylomorphic pluralism as a position which, in the course of attempting to formulate a response to the Grounding Problem, also goes in for a reductive analysis of a compound's relation to its form. For example, the title of Section 2 of Sidelle's ‘Does Hylomorphism Offer a Distinctive Solution to the Grounding Problem?’ is ‘What is it for an object to have a form?’ and the question re-occurs numerous times throughout Sidelle's discussion. As Sidelle recognizes, robust hylomorphic pluralists, by contrast, reject the idea that they are obliged to give a reductive account of a compound's relation to its form, as part of their response to the Grounding Problem or for any other reason. In their view, after all, no further analysis in more basic terms can be given, or needs to be given, of a compound's relation to its form.

²⁷ Koslicki, The Structure of Objects, especially Chapter VII; and ‘Essence, Necessity and Explanation’, in Contemporary Aristotelian Metaphysics (ed.) Tahko, Tuomas (Cambridge: Cambridge University Press, 2012), 187–206Google Scholar.

²⁸ In Chapter II of Form, Matter, Substance, I consider and reject two main rival conceptions of matter: accounts which conceive of the matter composing an object as prime matter (e.g. Oderberg, Real Essentialism); and accounts which conceive of the matter composing an object as belonging to the ontological category of stuff (e.g. Markosian, Ned, ‘The Right Stuff’, Australasian Journal of Philosophy 93 (2015), 665–687CrossRefGoogle Scholar). The approach defended by Brower in Aquinas's Ontology of the Material World: Change, Hylomorphism, and Material Objects belongs to both camps, since Brower holds that the matter constituting matter-form compounds is prime matter; but he interprets prime matter as belonging to the ontological category of stuff.

²⁹ Very briefly, my argument in Chapter VII of The Structure of Objects goes as follows. In order to avoid a proliferation of primitive sui generis notions of parthood and composition, whose characteristics must be stipulatively imposed on them by means of distinct bodies of postulates (Fine, ‘Things and Their Parts’), I assume a single notion of parthood, at least for the domain of concrete particular objects, which satisfies at least the following minimal formal characteristics: Asymmetry, Transitivity, and Weak Supplementation. (The Weak Supplementation Principle states that an object which has a proper part must have at least another proper part disjoint from the first.) By Leibniz's Law, a whole is not identical to its proper parts, individually or collectively, since a whole and its proper parts are not indiscernible with respect to all of their properties. Next, it is plausible to think that a matter-form compound has its matter or material components as proper parts. Suppose now that it is possible for a whole (e.g. a statue) to be composed of just a single material component (e.g. a piece of clay). Then, by Weak Supplementation, the whole must have one or more additional proper parts besides its single material component. But the best candidates for these additional proper parts within the whole are of course its form or formal components. I conclude that a whole therefore has both its matter or material components and its form or formal components as proper parts, strictly and literally speaking and according to a single relation of proper parthood.

³⁰ I am focused here on scenarios in which a whole is composed of a single material component. In a scenario in which a whole is composed of more than one material component, its matter in my view is a plurality of material components. In that case, each of these material components, assuming that it is a structured whole, is itself a concrete particular object that is analyzed hylomorphically as a compound of matter and form. The more precise formulation of the hylomorphic conception of matter includes the following important proviso: the material parts of matter-form compounds are themselves matter-form compounds, unless or until we reach an empirically confirmed level in the compositional hierarchy at which the material parts of matter-form compounds are not themselves structured wholes. I discuss the possibility envisaged in the proviso in more detail in Chapter II of Form, Matter, Substance.

³¹ I discuss the structural constraints set by the form of a matter-form compound in Koslicki, The Structure of Objects. For the form's role in determining the numerical identity of matter-form compounds, see Form, Matter, Substance, Section III.4.3; and ‘Essence and Identity’. The unity of matter-form compounds is taken up in Form, Matter, Substance, Chapter VII. The three types of constraints I have just identified (i.e. constraints concerning the structure, identity and unity of a matter-form compound) are not intended to constitute an exhaustive list of all possible types of constraints which can be placed on an object's material components by the object's form. For one would expect, for example, that specific kinds of objects are governed by further formal constraints which do not generalize across the board. To illustrate, in the case of chemical kinds, for example, the material components composing a molecule, say, must be chemically bonded to one another by sharing electrons; but in the case of artifact kinds, the material components composing an ax, say, must be properly fastened to one another in a different way.

³² For diverging perspectives concerning the composition-as-identity model, see for example Lewis, David, Parts of Classes (Oxford: Basil Blackwell, 1991)Google Scholar; and Composition as Identity (eds) Cotnoir, Aaron J. and Baxter, Donald L. M. (Oxford: Oxford University Press, 2014)CrossRefGoogle Scholar.

³³ The position that a concrete particular object (e.g. Socrates) should be identified with the object's individual form (e.g. Socrates’ soul) is defended, for example, in Frede, Michael, ‘Substance in Aristotle's Metaphysics’, reprinted in his Essays in Ancient Philosophy (Minneapolis: University of Minnesota Press, 1987), 72–80Google Scholar; Michael Frede, ‘Individuals in Aristotle’, reprinted in his Essays in Ancient Philosophy, 49–71; Michael Frede and Günther Patzig, Aristoteles Metaphysik Z, Text, Übersetzung und Kommentar, Vols.1 and 2 (Munich: Verlag C. H. Beck); Lowe, ‘Form Without Matter’; Jennifer Whiting, Individual Forms in Aristotle, unpublished doctoral dissertation (Ithaca: Cornell University, 1984); Whiting, Jennifer, ‘Form and Individuation in Aristotle’, History of Philosophy Quarterly 3 (1986), 359–377Google Scholar; Whiting, Jennifer, ‘Metasubstance: Critical Notice of Frede-Patzig and Furth’, The Philosophical Review 100 (1991), 607–639CrossRefGoogle Scholar; and Whiting, Jennifer, ‘Living Bodies’, in Essays on Aristotle's De Anima, (ed.) Nussbaum, Martha C. and Rorty, Amélie Oksenberg (Oxford: Clarendon Press, 1992), 75–91Google Scholar.

³⁴ Beyond that, additional commitments concerning the precise specification of the essence of a matter-form compound require delving more deeply into what it means to be an object of a specific kind. To illustrate, for the specific case of artifacts, say, to state exactly what goes into the specification of an artifact's essence requires a commitment to a particular essentialist account of artifacts. But those who have proposed such accounts disagree with one another as to what exactly belongs into a proper specification of the essence of an artifact (e.g. its function, the particular creative intention guiding the artifact's maker, the artifact's original matter, the particular creative act in which the artifact's maker successfully exercised his or her creative intention, etc.). In addition, in the case of artifacts, we must of course confront the more general question as to whether a coherent and plausible essentialist account is even possible or appropriate, given that artifacts seem to be in certain ways dependent on human minds, interests, practices, and so forth. For further discussion of the particular case of artifacts, see for example Baker, Lynne Rudder, The Metaphysics of Everyday Life: An Essay in Practical Realism (New York: Cambridge University Press, 2007)CrossRefGoogle Scholar; Evnine, Making Objects and Events: A Hylomorphic Theory of Artifacts, Actions, and Organisms; Koslicki, Form, Matter, Substance, Chapter VIII; and Thomasson, Amie, ‘Realism and Human Kinds’, Philosophy and Phenomenological Research 67 (2003), 580–609CrossRefGoogle Scholar.

³⁵ As noted earlier, individual forms theorists have a range of options available to them, depending on whether they take individual forms to be objects, properties, relations, powers, states, functions, activities, processes, facts, actions, sui generis entities, or what have you. (In each case, the ontological category in question is of course construed as containing particulars as its members.) The robust construal of individual forms does not in itself favor one of these ontological categories over another; rather, it rules out certain conceptions of what the occupants of the relevant ontological category are like. The robust construal of forms requires that – regardless of what sorts of entities individual forms are – they cannot bear the very same relation both to the compound (essentially) and to the matter (accidentally). Thus, suppose for example that Socrates’ individual form is construed as a particularized property (e.g. a humanity trope) which essentially characterizes Socrates. Then, the robust construal requires that Socrates’ humanity trope does not also characterize Socrates’ matter, viz. his body, even accidentally, despite the fact that Socrates and Socrates’ body are of course spatiotemporally coincident for as long as Socrates is alive. Nevertheless, so the robust hylomorphic pluralist reasons, nothing that is human at all is human only accidentally. Therefore, even though Socrates’ body is spatiotemporally coincident with an object, viz. Socrates, which is characterized by Socrates’ humanity trope and is so essentially, Socrates’ body is not therefore also characterized by Socrates’ humanity trope, even accidentally.

³⁶ I said earlier that I will not lean on any special features concerning the specific example under discussion which arise from the fact that Lumpl and Goliath are artifacts, since I want to leave open the possibility that a similar case can in principle be constructed for living or non-living members of non-artifactual kinds as well. Given that Lumpl and Goliath are assumed to be artifacts, however, various options are available in this particular case which may not generalize to a case involving the members of natural kinds. For example, suppose that the expression, ‘statue’, singles out a genuine kind, but the expression, ‘piece of clay’, does not single out a genuine kind. Then, the plurality of material parts composing Goliath compose a matter-form compound which belongs to the kind, statue, but they fail to compose an additional matter-form, viz. the alleged piece of clay, Lumpl, which is spatiotemporally coincident but numerically distinct from the statue, Goliath. The strategy just outlined allows for a monist response to the particular case at hand. I consider the special features of artifacts in greater detail in Koslicki, Form, Matter, Substance, Chapter VIII.

³⁷ See especially Fine, Kit, ‘Essence and Modality’, Philosophical Perspectives 8 (1994)CrossRefGoogle Scholar, Logic and Language, 1–16; ‘Senses of Essence’, Modality, Morality, and Belief, Essays in Honor of Ruth Barcan Marcus (eds) Sinnott-Armstrong, Walter, Raffman, Diana, and Asher, Nicholas (New York: Cambridge University Press, 1995), 53–73Google Scholar; ‘The Logic of Essence’, Journal of Philosophical Logic 24 (1995), 241–273CrossRefGoogle Scholar. Other contemporary neo-Aristotelians, myself included, have also gravitated towards a non-modal conception of essence, e.g. Michael Gorman, E.J. Lowe, and David Oderberg. The conception of essence and necessity advanced by Bob Hale is similar in many ways to Fine's, though the label ‘non-modal’ strictly speaking does not apply to it, since Hale takes as basic certain modal truths, viz. the essential truths, from which other necessary truths are supposed to be derivable; see his Necessary Beings: An Essay on Ontology, Modality, and the Relations Between Them (New York: Oxford University Press, 2015)Google Scholar. For my purposes, however, we can subsume Hale's account under the label, ‘non-modal’, as it is used in the text, since I have in mind primarily approaches which reject the reduction of essence to modality and which hold instead that, if any such reduction is possible at all, it would have to proceed in the opposite direction. The contrasting model, which does take essence to be reducible to modality, dominated the metaphysical landscape for many decades starting in the 1970s. For some representative examples, see for example Forbes, Graeme, The Metaphysics of Modality (Oxford: Oxford University Press, 1985)Google Scholar; Lewis, David, On the Plurality of Worlds (Oxford: Basil Blackwell, 1986)Google Scholar; Mackie, Penelope, How Things Might Have Been: Individuals, Kinds, and Essential Properties (New York: Oxford University Press, 2009)Google Scholar; and Plantinga, Alvin, The Nature of Necessity (Oxford: Clarendon Press, 1974)Google Scholar.

³⁸ Koslicki, ‘Essence, Necessity and Explanation’.

³⁹ Koslicki, Form, Matter, Substance, Section III.4.3; and ‘Essence and Identity’.

⁴⁰ Koslicki, , ‘Varieties of Ontological Dependence’, in Metaphysical Grounding: Understanding the Structure of Reality (eds) Correia, Fabrice and Schnieder, Benjamin (Cambridge: Cambridge University Press, 2012), 186–213CrossRefGoogle Scholar; and ‘Essence, Necessity and Explanation’.

⁴¹ See also Hale's distinction between ‘direct’ and ‘indirect’ essential truths (Necessary Beings: An Essay on Ontology, Modality, and the Relations Between Them, 154). The direct essential truths are those propositions which are immediately, or directly, true in virtue of the nature of the entities under consideration, i.e. whose truth is guaranteed by the entity's definition. The indirect essential truths, in Hale's view, are those which logically follow from an entity's definition.

⁴² Aristotle divides up the causal responsibilities within a matter-form compound between the matter, which serves as the material cause of the hylomorphic compound, and the form, which serves as the formal, final and efficient cause of the hylomorphic compound. For further discussion of the causal priority Aristotle assigns to the form of a matter-form compound over the matter-form compound itself and its matter, see my ‘The Causal Priority of Form in Aristotle’, in Studia Philosophica Estonica 7/2 (2014), Special Issue: ‘Aristotelian Metaphysics: Essence and Ground’ (eds) Riin Sirkel and Tuomas Tahko, 113–141.

⁴³ This causal approach to essences is, for example, developed further in Peramatzis, Michail, ‘Aristotle's Hylomorphism: The Causal-Explanatory Model’, forthcoming in Metaphysics: Journal of the Canadian Metaphysics Collaborative, Vol. 1 (2018): “Hylomorphism”, edited by Cameron, Margaret, Koslicki, Kathrin, and Raven, Michael (Ubiquity Press)Google Scholar.