The standard semantics for counterfactuals ensures that any counterfactual with a true antecedent and true consequent is itself true. There have been many recent attempts to amend the standard semantics to avoid this result. I show that these proposals invalidate a number of further principles of the standard logic of counterfactuals. The case against the automatic truth of counterfactuals with true components does not extend to these further principles, however, so it is not clear that rejecting the latter should be (...) a consequence of rejecting the former. Instead I consider how one might defuse putative counterexamples to the truth of true-true counterfactuals. (shrink)

There was a long tradition in philosophy according to which good reasoning had to be deductively valid. However, that tradition began to be questioned in the 1960’s, and is now thoroughly discredited. What caused its downfall was the recognition that many familiar kinds of reasoning are not deductively valid, but clearly confer justification on their conclusions. Here are some simple examples.

It is commonplace to distinguish between propositional justification (having good reasons for believing p) and doxastic justification (believing p on the basis of those good reasons).One necessary requirement for bridging the gap between S’s merely having propositional justification that p and S’s having doxastic justification that p is that S base her belief that p on her reasons (propositional justification).A plausible suggestion for what it takes for S’s belief to be based on her reasons is that her reasons must contribute (...) causally to S’s having that belief. Though this suggestion is plausible, causal accounts of the basing relation that have been proposed have not fared well. In particular, cases involving causal deviancy and cases involving over-determination have posed serious problems for causal accounts of the basing relation. Although previous causal accounts of the basing relation seem to fall before these problems, it is possible to construct an acceptable causal account of the basing relation. That is, it is possible to construct a causal account of the basing relation that not only fits our intuitions about doxastic justification in general, but also is not susceptible to the problems posed by causal deviancy and causal over-determination. The interventionist account of causation provides the tools for constructing such an account. My aim is to make use of the insights of the interventionist account of causation to develop and defend an adequate causal account of the basing relation. (shrink)

After reviewing several failed arguments that laws cannot change, I use the laws' special relation to counterfactuals to show how temporary laws would have to differ from eternal but time-dependent laws. Then I argue that temporary laws are impossible and that neither Lewis's nor Armstrong's analyses of law nicely accounts for the laws' immutability. *Received September 2006; revised September 2007. ‡Many thanks to John Roberts and John Carroll for valuable comments on earlier drafts, as well as to several anonymous referees (...) for their good suggestions. †To contact the author, please write to: Department of Philosophy, University of North Carolina, CB #3125, Caldwell Hall, Chapel Hill, NC 27599-3125; e-mail: [email protected]. (shrink)

In this article I offer an approach to counterfactuals based on a notion of objective probability. It is in the spirit of, though it does not fall squarely under, the metalinguistic model. Thus, it is not developed in terms of possible worlds, or notions parasitic on them (e.g., similarity). Its dominant features are rooted in objective probability and causal relevance (analyzed probabilistically), and thus it is not close in spirit to a maximal similarity or a minimal change approach.

While standard first-order modal logic is quite powerful, it cannot express even very simple sentences like “I could have been taller than I actually am” or “Everyone could have been smarter than they actually are”. These are examples of cross-world predication, whereby objects in one world are related to objects in another world. Extending first-order modal logic to allow for cross-world predication in a motivated way has proven to be notoriously difficult. In this paper, I argue that the standard accounts (...) of cross-world predication all leave something to be desired. I then propose an account of cross-world predication based on quantified hybrid logic and show how it overcomes the limitations of these previous accounts. I will conclude by discussing various philosophical consequences and applications of such an account. (shrink)

A counteridentical is a counterfactual with an identity statement in the antecedent. While counteridenticals generally seem non-trivial, most semantic theories for counterfactuals, when combined with the necessity of identity and distinctness, attribute vacuous truth conditions to such counterfactuals. In light of this, one could try to save the orthodox theories either by appealing to pragmatics or by denying that the antecedents of alleged counteridenticals really contain identity claims. Or one could reject the orthodox theory of counterfactuals in favor of a (...) hyperintensional semantics that accommodates non-trivial counterpossibles. In this paper, I argue that none of these approaches can account for all the peculiar features of counteridenticals. Instead, I propose a modified version of Lewis’s counterpart theory, which rejects the necessity of identity, and show that it can explain all the peculiar features of counteridenticals in a satisfactory way. I conclude by defending the plausibility of contingent identity from objections. (shrink)

I develop a theory of counterfactuals about relative computability, i.e. counterfactuals such as 'If the validity problem were algorithmically decidable, then the halting problem would also be algorithmically decidable,' which is true, and 'If the validity problem were algorithmically decidable, then arithmetical truth would also be algorithmically decidable,' which is false. These counterfactuals are counterpossibles, i.e. they have metaphysically impossible antecedents. They thus pose a challenge to the orthodoxy about counterfactuals, which would treat them as uniformly true. What’s more, I (...) argue that these counterpossibles don’t just appear in the periphery of relative computability theory but instead they play an ineliminable role in the development of the theory. Finally, I present and discuss a model theory for these counterfactuals that is a straightforward extension of the familiar comparative similarity models. (shrink)

Different similarity relations on sets are introduced, and their logical properties are investigated. Close relationships are shown to hold between similarity relations that are based on symmetrical difference and operators of belief contraction that are based on relational selection functions. Two new rationality criteria for minimal belief contraction, the maximizing property and the reducing property, are proposed.

Recently, Cohen and Timmerman, 1–18, 2016) argue that actualism has control issues. The view should be rejected, they claim, as it recognizes a morally irrelevant distinction between counterfactuals over which agents exercise the same kind of control. Here we reply on behalf of actualism.

Heightened awareness of the origins of our moral judgments pushes many in the direction of moral skepticism, in the direction of thinking we are unjustified in holding our moral judgments on a realist understanding of the moral truths. A classic debunking argument fleshes out this worry: the best explanation of our moral judgments does not appeal to their truth, so we are unjustified in holding our moral judgments. But it is unclear how to get from the explanatory premise to the (...) debunking conclusion. This paper shows how to get from here to there by way of epistemic insensitivity. First, we reconstruct Richard Joyce’s evolutionary debunking argument from insensitivity. Second, we raise epistemological difficulties for Joyce’s argument. Third, we develop and defend a new debunking argument from insensitivity. (shrink)

Let us call a statement of the form ‘If A was, is, or will be the case, then C was, is, or will be the case’ an indicative conditional. And let us call a statement of the form ‘If A had been, were, or were to be the case, then C would have been, would be, or would come to be the case’ a subjunctive, or counterfactual, conditional.

This discussion note examines a recent argument for the principle that any counterfactual with true components is itself true. That argument rests upon two widely accepted principles of counterfactual logic to which the paper presents counterexamples. The conclusion speculates briefly upon the wider lessons that philosophers should draw from these examples for the semantics of counterfactuals.

The gist of modal epistemology is expressed in the idea that you fail to know if you do believe truly but it is seriously possible for you to believe falsely. According to subjunctivism, this idea is captured by certain subjunctive conditionals. One formulation invokes a safety condition—“If S had believed P, then P would have been the case,” while the other invokes a sensitivity condition—“If P had been false, S would not have believed that P.” According to simple subjunctivism, such (...) conditionals do not contrapose and Sosa derives important epistemological consequences which favor safety from this difference. However, simple subjunctivism is inadequate. I return to Goodman and his analysis of factuals and propose modal stability, which is restricted sensitivity or enhanced safety as a proper epistemic condition for the non-accidental connection between the basis for the belief and the relevant facts of the matter. The idea of modal stability combines robustness (benefi ts of safety) with responsiveness to facts (benefi ts of sensitivity) and recovers the original motivation for the relevant alternatives theory—when testing for claims of knowledge that p we ask what might be the case if not-p, but we ignore irrelevant possibilities. Epistemic modal conditions should be expressed in terms of conditionals of connection which contrapose within the limits of relevance. (shrink)

From an indeterminist's perspective, I support and defined the following argument for deontic incompatibilism: If determinism is true, then no one ever can do otherwise than he does. If no one ever can do otherwise than he does, then nothing anyone does is ever right, wrong, or obligatory. Therefore, if determinism is true, then nothing anyone does is ever right, wrong, or obligatory. ;They sense of 'can' I use in this argument is what I call "the power-'can' of ordinary language." (...) The power-'can' has two time indexes; one applies to the power itself, the other to the relevant doing. I argue that the power-'can' is a sense of 'can' with which the "ought implies can" principle holds true. ;I review and respond to various accounts of 'can' proposed by compatibilists Bruce Aune, Keith Lehrer, David Lewis, G. E. Moore and others. Elsewhere I discuss writings by Peter van Inwagen and J. L. Austin. ;To support , I utilize, argue for, and show the advantages of the Temporal Physical Possibility Requirements: If an agent, S, can at time T do A at time T$\sp\prime$, then S's doing A at $T\sp\prime$ is jointly possible with the conjunction of the state of the world at T and the laws of nature. When arguing for these requirements, I focus on how most people use the power-'can' and how they would use it in various situations. I present and respond to objections to my arguments. Most of the objections are based on certain strong forms of contextualism. ;I argue for and defend my premises against various objections. One objection is based on a form of utilitarianism advocated by Fred Feldman. Other objections are based on an example by Harry Frankfurt concerning moral responsibility. ;Two arguments against are presented and I respond. They are developed from a suggestion by John Martin Fischer that people would continue making deontic claims if a consortium of scientists were to find strong evidence of determinism. (shrink)