Varieties of dispositional essentialism about natural laws

An important task for metaphysicians and philosophers of science is to account for laws of nature – in particular, how they distinguish themselves from ‘mere’ regularities, and the modal force they are endowed with, ‘natural necessity’. Dispositional essentialism about laws (for short: ‘essentialism’) is roughly the view that laws distinguish themselves by being grounded in the essences of natural entities (e.g. kinds, properties). This paper does not primarily concern how essentialism compares to its main rivals – Humeanism and Armstrongeanism. Rather, it distinguishes and comparatively assesses various brands of essentialism – which mainly differ as to where exactly they take laws to find their essentialist sources (e.g. in particular entities, like electrons, or in larger pluralities of entities, or in the world as a whole), and what they take to be the targets of laws, namely what they apply to. Yet, this internal comparison is not unrelated to the more general debate about laws: the main criteria with which I compare these essentialist views concern how they can deal with some of the main objections faced by essentialism in general (the modal status it typically attributes to laws, which some think is too strong; and its alleged incapacity to account for the most 'general' laws, like conservation laws), and how they can keep what is arguably the main intuitive advantage of essentialism over its rivals (the fact that, on this view, things “govern themselves”). Thus, the paper also concerns the relative position of essentialism in the larger debate about laws – ultimately bringing support to it.

The Fundamentality of Fundamental Powers

Dispositional essentialism is the view that all or many fundamental properties are essentially dispositional, or powers. The literature on the dispositional essence of powers is abundant. In contrast, the question of how to understand the fundamentality of fundamental powers has received scarce interest. Therefore, the fundamentality of powers stands in need of clarification. There are four main conceptions of the fundamental, namely as that which is (i) metaphysically independent; or (ii) belonging to a minimally complete basis; or (iii) perfectly natural; or (iv) metaphysically primitive. Here, I present and discuss each of these approaches from the viewpoint of dispositional essentialism. I show that (i) is incompatible with the metaphysics of powers and (ii)–(iv) have more drawbacks than merits. Therefore, my conclusion is that the dispositional essentialist should seek an alternative. Although I offer no positive account, I pave the way to more fruitful views by identifying the shortcoming of these unpromising options.

Induction and Natural Kinds Revisited

Howard Sankey reconsiders a special issue closely connected with causal powers—the problem of induction. He addresses a deep version of problem of circularity originally raised by Psillos, and argues that the circularity can be avoided. The key is recognizing certain epistemically externalist results of the Megaric consequences of the commitment to dispositional essentialism. Circularity can be avoided, Sankey argues, because it is the way the world is, rather than the inductive inference itself, that grounds the reliability of the inductive inference in his previous account. What are doing the work for Sankey here are the Megaric consequences of his adoption of Ellis’s dispositional essentialism. The uniformity in question is one that stretches across possible worlds: nature is uniform in the precise sense that there are natural kinds whose members all possess a shared set of essential properties. The significance of this commitment lies in how the possible and the temporal intersect through restrictions placed on the accessibility relation between the actual and the possible. Ipso facto, when considering questions about the future behaviours of objects, which is how Sankey understands the problem of induction to be, the uniformity of nature can ground the reliability of beliefs about those future behaviours precisely because the domain of possibility is restricted to those worlds accessible to the actual world, which is fixed by the commitments of dispositional essentialism.

Causal Powers and Structures

Brian Ellis provides a detailed and systemic overview of his version of dispositional essentialism. Ellis is famous for having developed and defended a mixed ontology for scientific realism. This is a robustly Aristotelian ontology that involves a mix of categorical and essentially dispositional properties inhering as universal in individualized entities. In this contribution, Ellis briefly defends this sort of ontology by arguing that it, or something very much like it, is necessary to provide an account of the system of reality discovered through modern science. It is, moreover, entirely adequate for the job of accounting for the ontology of modern science. He then turns to consider three objections to his ontology. The first is what other contributors will call the ‘directedness problem’, which is the idea that powers are directed at their manifestation in a way analogous to the directedness of intentionality. The second is what other contributors call the ‘intrinsicness problem’, which is the idea that causal powers are intrinsic to or inhering in their subject. The third is what other contributors call the ‘necessity problem’, which is the idea that there is something important and distinctive about metaphysical necessity vis-à-vis logical necessity.

Reconsidering the Dispositional Essentialist Canon

Dispositional Essentialism is a unified anti-Humean account of the metaphysics of low-level physical properties and laws of nature. In this paper, I articulate the view that I label Canonical Dispositional Essentialism (CDE), which comprises a structuralist metaphysics of properties and an account of laws as relations in the property structure. I then present an alternative anti-Humean account of properties and laws (still somewhat in the dispositional essentialist spirit). This account rejects CDE’s structuralist metaphysics of properties in favour of a view of properties as qualitative grounds of dispositions and it rejects CDE’s view of laws as relations in favour of a view of laws as features of an efficient description of possible property distributions. I then defend this view over CDE on the grounds that it can overcome an explanatory shortcoming of CDE and that it achieves a level of continuity with science that CDE fails to achieve. The upshot of this paper is a significant narrowing of the range of possibilities in which the absolutely best unified account of laws and properties resides.

Five Sources of Contingency for Dispositionalism

Law dispositionalism is the doctrine according to which laws of nature are grounded on powers/dispositions. In this article, I shall examine how certain laws of nature can turn out to be contingent on this view. First of all, I shall distinguish between two versions of law dispositionalism (i. e. a weak and a strong one) and I shall also single out two further theses that may be conjoined with it (i. e. strong and weak dispositional essentialism). I shall also single out four different sorts of laws of nature. Afterwards, I shall examine five sources of contingency for law dispositionalism: the contingent existence of the relevant entities involved in the laws; the contigent activation, background and possession conditions of the powers at stake; the presence of contingent constants in the laws; the presence of indeterministic powers; the presence of powers that are not essential to the entities involved in the laws.

Dispositional Essentialism, Directedness, and Inclination to an End

Dispositional essentialists U. T. Place, George Molnar, and C. B. Martin hold that dispositions are intrinsically directed to their manifestations. Thomists have noted that this directedness is similar to Thomistic directedness to an end. I argue that Place, Molnar, and Martin would benefit from conceiving of dispositional directedness as the sort of directedness associated with Thomistic inclinations. Such Thomistic directedness can help them to account for the production of manifestations; to justify their reliance on dispositional directedness; to show the causal relevance of dispositions; and to motivate their view that dispositions are not reducible to categorical bases. I argue, moreover, that Thomistic inclination to an end does not succumb to the most common objections to finality: it is not mentalistic or vitalistic, and it does not involve backwards causation. Place, Molnar, and Martin, therefore, can embrace the directedness associated with Thomistic inclination—and reap its benefits—without incurring any high metaphysical cost.