Alan Sidelle

This paper defends the traditional view that the laws of nature are contingent, or, if some of them are necessary, this is due to analytic principles for the individuation of the law-governed properties. Fundamentally, I argue that the supposed explanatory purposes served by taking the laws to be necessary --showing how laws support counterfactuals, how properties are individuated, or how we have knowledge of properties--are in fact undermined by the continued possibility of the imagined scenarios--this time, described neutrally--which seemed to disprove the claim to necessity in the first place. I speculate that this will be true for any proposed necessary a posteriori truths, and is a basis for rejecting their supposed metaphysical significance.

Philosophy and science employ abstract hypothetical scenarios- thought experiments - to illustrate, defend, and dispute theoretical claims. Since thought experiments furnish no new empirical observations, the method prompts two epistemological questions: whether anything may be learnt from the merely hypothetical, and, if so, how. Various sceptical arguments against the use of thought experiments in philosophy are discussed and criticized. The thesis that thought experiments in science provide a priori knowledge through non-sensory grasping of abstract entities is discussed and rejected. The thesis that thought experimentation consists in manipulations of mental models is examined and found to be of limited epistemological relevance. It is argued that thought experiments are associated with characteristic arguments in a manner similar to ordinary experiments. It is further argued that thought experiments function in the same way as experiments in general: by providing premises for their associated arguments. Like other experiments, a thought experiment is successful when the premises it provides are true. This holds both for philosophical and scientific thought experiments. An argument schema is proposed and shown to be a formal analogue to that associated with ordinary experiments; similar in being subject to epistemological holism; but differing in being modal: in employing statements about possibility and necessity. The evaluation of thought experiments thus depends on how modal statements may be justified. Intuition and conceivability are discussed as sources of modal justification and found problematic. Instead it is suggested that evaluation proceed by accommodation of the statements describing the experiment's hypothetical scenario. The method of accommodation is developed and applied to five influential thought experiments in philosophy: the brain in a vat; Putnam's Twin Earth; Burge's arthritis example; Searle's Chinese Room; and Newcomb's problem. Its application shows some of these to be failed, others to be successful only relative to controversial philosophical doctrines

One common objection to Conventionalism about modality is that since it is contingent what our conventions are, the modal facts themselves will thereby be contingent. A standard reply is that Conventionalists can accept this, if they reject the S4 axiom, that what is possibly possible is possible. I first argue that this reply is inadequate, but then continue to argue that it is not needed, because the Conventionalist need not concede that the contingency of our conventions has any bearing on the modal status of necessary truths. It is explained why this does not compromise the Conventionalist claim that necessity – and particularly, essence – is due to conventions

A not-unpopular position in the metaphysics of material objects (Ted Sider's, for instance) combines realism about what objects there are and the conditions of objecthood with conventionalism about de re modality. I argue that this is not a coherent combination of views: one must go fully conventionalist, or fully realist. The central argument displays the difficulty for the modal conventionalist/object realist in specifying the object that satisfies de re modal predicates. I argue that if this is a mind-independent object, contradictions arise when we consider the possibility or actuality of non-equivalent conventions both applying to 'the same object'.

The idea that disputes which are heated, and apparently important, may nonetheless be 'merely verbal' or 'just semantic' is surely no stranger to any philosopher. I urge that many disputes, both in and out of philosophy, are indeed plausibly considered verbal, and that it would repay us to more frequently consider whether they are so or not. Asking this question is what I call ‘The Method of Verbal Dispute’. Neither the notion nor the method of verbal dispute is new. What I do here is to urge its wider application, to suggest how widespread is the phenomenon of verbal disputes, and to clarify certain misconceptions about what is, or needs to be, involved in a verbal dispute. One central claim is that verbal disputes need not be ‘merely’ verbal disputes – that often, there is a real disagreement to be had, but it is not the one suggested by the surface form of the disagreement. I also discuss the relation between verbal disputes, relativism and cases in which ‘there is no fact of the matter’

In “Innocuous Infallibility,” Earl Conee argues that the infallibility to which I argue Internalism is committed, in “An Argument that Internalism Requires Infallibility,” is harmless and trivial. I maintain that this overlooks the fact that Internalism makes use of an intuitive notion of ‘epistemic twinhood’ to drive its position, rather than one antecedently defined with a filled‐out notion of ‘relevant epistemic circumstances’. Conee is correct that any theory requires, and trivially gets, some sort of infallibility‐but it is not trivial that there is a coherent and univocal notion of the sort of relevant circumstances‐and so, twinhood and infallibility‐behind the Internalist strategy and motivation.

Many philosophers believe that identity through time cannot depend on features extrinsic to the relata and relations between them. This goes with the view that one must deny identity in cases for which there is a ‘duplication case’-a case just like the first, but for an additional, ‘external’ element which provides an equal or better ‘candidate’ for identity with one of the relata. Such friends of intrinsicness cannot remedy the failure of continuity of function/form to be one-one by non-branching or closest competitor clauses. The obvious intrinsic approach-perhaps taken for granted-appeals to considerations of quantity of matter, requiring over 50% shared matter between identicals . But this rules out plausible cases of halving and doubling for which there are not duplication cases. After bringing out this problem, I ask what makes duplication cases possible, and use this to formulate an intrinsic condition which allows identity whenever there is continuity of function, but no threat to intrinsic ness via duplication cases

One obvious solution to the puzzles of apparently coincident objects is a sort of reductionism - the tree really just is the wood, the statue is just the clay, and nothing really ceases to exist in the purported non-identity showing cases. This paper starts with that approach and its underlying motivation, and argues that if one follows those motivations - specifically, the rejection of coincidence, and the belief that 'genuine' object-destroying changes must differ non-arbitrarily from accidental changes, that one can plausibly be pushed to an extreme nihilism, that denies the existence of any objects at all.

The Aristotelian doctrine of hylomorphism has seen a recent resurgence of popularity, due to the work of a number of well-known and impressive philosophers. One of the recently motivating virtues claimed for the doctrine is its ability to solve the grounding problem for philosophers who believe in coinciding entities. In this brief article, I will argue that when fully spelled out, hylomorphism does not, in fact, contribute a distinctive solution to this problem. It is not that it offers no solution at all, but that it is not really a different solution from other familiar, seemingly non-hylomorphic, solutions on offer

This paper lays out the basic structure of any view involving coincident entities, in the light of the grounding problem. While the account is not novel, I highlight fundamental features, to which attention is not usually properly drawn. With this in place, I argue for a number of further claims: The basic differences between coincident objects are modal differences, and any other differences between them need to be explained in terms of these differences. More specifically, the basic difference is not a difference in sort. A number of recent defenses of coincidence, which share the basic structure I outline, misidentify what, in their accounts, plays the basic role of addressing the grounding problem. More tentatively, I argue Coincident entities differ only in these modal properties, and properties they entail. In particular, they do not differ in properties like ‘being a tree,’ ‘being a statue,’ or aesthetic properties, and finally in light of how the account of coincidence offered addresses the grounding problem, the grounding problem provides no reason to prefer monism to pluralism.

Grounding has become all the rage in recent philosophical work and metaphilosophical discussions. While I agree that the concept of ground marks something useful, I am skeptical about the metaphysical weight many imbue it with, and the picture of ‘worldly layering’ that grounding talk inspires. My skepticism centers around the fact that grounding involves necessitation, combined with reasons for thinking matters of necessity are matters of logical or conceptual (semantic, psychological) relations. I sketch an argument for deflationism about ground based on this sort of deflationism about necessity and essence. I also note that in at least some cases, the considerations supporting modal deflationism directly support deflationism about whatever grounding relations may obtain in these cases.

Some relations - like supervenience and composition - can appear very much like identity. Sometimes, the relata differ only in modal, or modally-involved features. Yet, in some cases, we judge the pairs to be identical (water/H2O; Hesperus/Phosphorus), while in others, many judge one of the weaker relations to hold (c-fiber firing/pain; statues/lumps). Given the seemingly same actual properties these pairs have, what can justify us in sometimes believing identity is the relation, and sometimes something weaker? I argue that it can only be knowledge of differences of individuative criteria that we know a priori because they are built into the meanings of the words/concepts involved. Possible metaphysical conclusions are considered.

Most contemporary internalists are fallibilists, denying that there need be anything about which we are infallible for us to have knowledge or justified beliefs. At the same time, internalists standardly appeal to ‘internal twins’ in arguing against externalism and motivating internalism---a Cartesian demon can ruin the ‘external’ relations we have to the world, but one is equally well justified in one’s beliefs whether or not one is subject to such deception. Even if one doesn’t motivate one’s internalism by appeal to internal twins, any internalist must agree that internal twins are equally well justified in their beliefs. I argue that the internal twins argument for, or commitment of internalism, commits one to the claim that the conditions in virtue of which one is justified must be ones about which a believer is infallible. The basic argument is that for anything about which one can be mistaken, one has an internal twin who is mistaken, but is equally well justified---and so, not in virtue of that about which one can be mistaken. If the argument can be resisted, this should tell us something useful about how to properly understand both internalism in general, and the idea of internal twins in particular

In section 96 of Reasons and Persons, Derek Parfit offers his now familiar tripartite distinction among candidates for ‘what matters’: (1) Relation R with its normal cause; (2) R with any reliable cause; (3) R with any cause. He defends option (3). This paper tries to show that there is important ambiguity in this distinction and in Parfit's defence of his position. There is something strange about Parfit's way of dividing up the territory: I argue that those who have followed him in viewing the choice among (1)–(3) as the (or an) important question in thinking about ‘what matters’ are mistaken, and that they bypass what seems to be a more important, even crucial, set of options and considerations. I am less concerned with what he does say than with what he ought to say, given his intuitions and arguments, and the general framework within which he is working. And I am particularly concerned to show that whether or not I am correct about what he is doing with his tripartite distinction, it is a distinction with which we should not be particularly concerned in the analysis either of what matters or of psychological continuity

I offer an understanding of what it is for a term to be rigid which makes no serious metaphysical commitments to or about identity across possible worlds. What makes a term rigid is not that it 'refers to the same object(property) with respect to all worlds' - rather (roughly) it is that the criteria of application for the term with respect to other worlds, when combined with the criteria of identity associated with the term, ensure that whatever meets the criteria of identity also meets the criteria of application and vice versa - in the simplest case, the criteria of application just are the criteria of identity - but things can be more complex to allow for the necessary a posteriori. This makes rigidity a non-metaphysically loaded semantic matters, and allows us to see that the phenomenon of and involving rigidity - especially the necessary a posteriori - are of no metaphysical significance on their own.

Alan Sidelle's Necessity, Essence, and Individuation is a sustained defense of empiricism—or, more generally, conventionalism—against recent attacks by realists. Sidelle focuses his attention on necessity a posteriori, a kind of necessity which contemporary realists have taken to support realism over empiricism. Turning the tables against the realists, Sidelle argues that if there are in fact truths necessary a posteriori, it is not realism, but rather empiricism which provides the best explanation for them.

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.