Many philosophers accept some version of a principle that says for all x, if x exists, then x plays a unique causal role. After briefly clarifying one version of the principle in Section 1, Section 2 gives reasons to doubt it by showing that there are non-identical “causal indiscernibles”—I call them “married causes.” Section 3 then sketches a few philosophical puzzles for which married causes may be helpful.

One of the traditional desiderata for a metaphysical theory of laws of nature is that it be able to explain natural regularities. Some philosophers have postulated governing laws to fill this explanatory role. Recently, however, many have attempted to explain natural regularities without appealing to governing laws. Suppose that some fundamental properties are bare dispositions. In virtue of their dispositional nature, these properties must be (or are likely to be) distributed in regular patterns. Thus it would appear that an ontology (...) including bare dispositions can dispense with governing laws of nature. I believe that there is a problem with this line of reasoning. In this essay, I’ll argue that governing laws are indispensable for the explanation of a special sort of natural regularity: those holding among categorical properties (or, as I’ll call them, categorical regularities). This has the potential to be a serious objection to the denial of governing laws, since there may be good reasons to believe that observed regularities are categorical regularities. (shrink)

Natural-kind essentialism faces an important but neglected difficulty: the problem of complex essences (PCE). This is the question of how to account for the unity of an instantiated kind-essence when that essence consists of multiple distinct properties, some of which lack an inherent necessary connection between them. My central goal here is to propose an essentialism-friendly solution to this problem. Along the way I also employ some points from that solution to argue for the necessary truth of essentialism (necessary, that (...) is, in all possible worlds in which there are material objects), and to support the essentialist ontology of laws over and against a major rival. (shrink)

The work is the presentation of a logical theory - Logic in Reality (LIR) - and of applications of that theory in natural science and philosophy, including ...

This paper discusses recent attempts to use essentialist arguments based on the work of Kripke and Putnam to ground causal necessity in the world. I argue in particular that arecent argument by Alexander Bird relies on controversial intuitions about the natures of substances which no Humean would accept. While a case can be made that essentialism reflects some assumptions within scientific practice, the same can be said of Humeanism; ultimately neither Bird’s arguments, nor any empirical facts, can decide the question (...) for or against Humeanism. (shrink)

This thesis aims to develop a psychologically plausible account of concepts by integrating key insights from philosophy (on the metaphysical basis for concept possession) and psychology (on the mechanisms underlying concept acquisition). I adopt an approach known as informational atomism, developed by Jerry Fodor. Informational atomism is the conjunction of two theses: (i) informational semantics, according to which conceptual content is constituted exhaustively by nomological mind–world relations; and (ii) conceptual atomism, according to which (lexical) concepts have no internal structure. I (...) argue that informational semantics needs to be supplemented by allowing content-constitutive rules of inference (“meaning postulates”). This is because the content of one important class of concepts, the logical terms, is not plausibly informational. And since, it is argued, no principled distinction can be drawn between logical concepts and the rest, the problem that this raises is a general one. An immediate difficulty is that Quine’s classic arguments against the analytic/synthetic distinction suggest that there can be no principled basis for distinguishing content-constitutive rules from the rest. I show that this concern can be overcome by taking a psychological approach: there is a fact of the matter as to whether or not a particular inference is governed by a mentally-represented inference rule, albeit one that analytic philosophy does not have the resources to determine. I then consider the implications of this approach for concept acquisition. One mechanism underlying concept acquisition is the development of perceptual detectors for the objects that we encounter. I investigate how this might work, by drawing on recent ideas in ethology on ‘learning instincts’, and recent insights into the neurological basis for perceptual learning. What emerges is a view of concept acquisition as involving a complex interplay between innate constraints and environmental input. This supports Fodor’s recent move away from radical concept nativism: concept acquisition requires innate mechanisms, but does not require that concepts themselves be innate. (shrink)

forthcoming in Philosophy and Phenomenological Research.

Two related claims have lately garnered currency: dispositional essentialism—the view that some or all properties, or some or all fundamental properties, are essentially dispositional; and the claim that laws of nature (or again, many or the fundamental ones) are metaphysically necessary. I have argued elsewhere (On the metaphysical contingency of laws of nature, Oxford University Press, Oxford, 2002) that the laws of nature do not have a mind-independent metaphysical necessity, but recent developments on dispositions have given these ideas a new (...) vibrancy and made them the topic of more focused discussion. So I would like to revisit this, arguing that the new work, as interesting and important as it is to our understanding of fundamental properties, powers and dispositions, should not change our minds about metaphysical necessity. One should still think necessity is conceptually or conventionally grounded. I do not argue that laws of nature are not necessary, nor that properties do not have dispositional essences, but only that if these are the case, then, like other de re or empirical necessities, they have no metaphysical weight and are based in our rules or decisions about how to talk about the world. We may have excellent reasons to talk and think in this way—but these reasons do not include, require or provide evidence of mind-independent metaphysical necessity or essences. (shrink)

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 then define 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 contingent 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. (shrink)

Non‐Humean theories of natural necessity invoke modally‐laden primitives to explain why nature exhibits lawlike regularities. However, they vary in the primitives they posit and in their subsequent accounts of laws of nature and related phenomena (including natural properties, natural kinds, causation, counterfactuals, and the like). This article provides a taxonomy of non‐Humean theories, discusses influential arguments for and against them, and describes some ways in which differences in goals and methods can motivate different versions of non‐Humeanism (and, for that matter, (...) Humeanism). In short, this article provides an introduction to non‐Humeanism concerning the metaphysics of laws of nature and natural necessity. (shrink)