A counterlegal is a counterfactual conditional containing an antecedent that is inconsistent with some set of laws. A backtracker is a counterfactual that tells us how things would be at a time earlier than that of its antecedent, were the antecedent to obtain. Typically, theories that evaluate counterlegals appropriately don’t evaluate backtrackers properly, and vice versa. Two cases in point: Lewis’ ordering semantics handles counterlegals well but not backtrackers. Hiddleston’s :632–657, 2005) causal-model semantics nicely handles backtrackers but not (...) counterlegals. Taking Hiddleston’s account as a starting point, I offer steps toward a theory capable of handling both counterlegals and backtrackers. The core contribution of this paper is a means for evaluating counterlegals relative to minimally-illegal models. (shrink)

Necessitarian accounts of the laws of nature meet an apparent difficulty: for them, counterlegal conditionals, despite appearing to be substantive, seem to come out as vacuous. I argue that the necessitarian may use the presuppositions of counterlegal discourse to explain this. If the typical presupposition that necessitarianism is false is made explicit in counterlegal utterances, we obtain sentences such as 'If it turns out that the laws of nature are contingent, then if the laws had been otherwise, then such and (...) such would have been the case', which are non-vacuous and very often true. This goes a long way towards resolving the difficulty for necessitarianism. (shrink)

Necessitarian accounts of the laws of nature have an apparent difficulty in accounting for counterlegal conditionals because, despite appearing to be substantive, on the necessitarian thesis they are vacuous. I argue that the necessitarian may explain the apparently substantive content of such conditionals by pointing out the presuppositions of counterlegal discourse. The typical presupposition is that a certain conceptual possibility has been realized; namely, that necessitarianism is false. (The idea of conceptual possibility is explicated in terms of recent work in (...) two-dimensional modal semantics.) If this sort of presupposition is made explicit in counterlegal utterances, we obtain a sentence such as: 'If it turns out that the laws of nature are contingent, then if the laws had been otherwise, then such and such would have been the case.' Sentences of this type are non-vacuous, and very often true. I argue that this goes a long way towards resolving the difficulty for necessitarianism. (shrink)

In his 2003 paper, “Does the Existence of Mathematical Objects Make a Difference?”, Alan Baker criticizes what he terms the ‘Makes No Difference’ (MND) argument by arguing that it does not succeed in undermining platonism. In this paper, I raise two objections. The first objection is that Baker is wrong in claiming that the premise of the MND argument lacks a truth-value. The second objection is that the theory of counterlegals which he appeals to in his argument is incompatible (...) with actual scientific practice. I conclude that we ought not to accept Baker’s claim. (shrink)

In his 2003 paper, "Does the Existence of Mathematical Objects Make a Difference?", Alan Baker criticizes what he terms the 'Makes No Difference' argument by arguing that it does not succeed in undermining platonism. In this paper, I raise two objections. The first objection is that Baker is wrong in claiming that the premise of the MND argument lacks a truth-value. The second objection is that the theory of counterlegals which he appeals to in his argument is incompatible with (...) actual scientific practice. I conclude that we ought not to accept Baker's claim. (shrink)

Substantive counterlegal discourse poses a problem for those according to whom the laws of nature are metaphysically necessary. I discern two types of necessitarianism about laws: dispositional essentialism and modal necessitarianism. I argue that Toby Handfield’s response to the problem of counterlegals cannot help the modal necessitarian, according to whom all possible worlds are identical with respect to the laws. I thus propose a fictionalist treatment of counterlegals. Fictions are not limited by metaphysical possibility; hence, fictionalism affords the (...) modal necessitarian the means to account for the apparent substance of counterlegals even granting the metaphysical necessity of the laws. (shrink)

Contrasting accounts of physicalism and strong emergentism face two problems. According to the neutrality problem, contrasting supervenience-based formulations of these positions cannot be neutral with respect to certain unrelated metaphysical commitments. According to the collapse problem, emergent properties can be accounted for using an appropriately expansive physical ontology, rendering strong emergentism metaphysically suspect. I argue that both these problems can be solved with a principled distinction between emergent causal laws and physical laws. I propose such a distinction based on a (...) finite discontinuity in the behavior of fundamental physical constituents as a function of complexity. (shrink)