Acta Analytica

Every Proposition is a Counterfactual Abstract I present and discuss two logical results. The first shows that a non-trivial counterfactual analysis exists for any contingent proposition that is false in at least two possible worlds. The second result identifies a set of conditions that are individually necessary and jointly sufficient for the success of a counterfactual analysis. I use these results to shed light on the question whether disposition ascribing propositions can be analyzed as Stalnaker-Lewis conditional propositions. The answer is that they can, but, in order for a counterfactual analysis to work, the antecedent and consequent must be related in a particular way, and David Lewis’s Time’s Arrow constraints on comparative world similarity must be relaxed. The upshot is that counterfactual analyses are easy to come by, in principle, even if not in practice. In that sense, it’s easy to be iffy.

Buttresses of the Turing Barrier Abstract The ‘Turing barrier’ is an evocative image for 0′, the degree of the unsolvability of the halting problem for Turing machines—equivalently, of the undecidability of Peano Arithmetic (PA). The ‘barrier’ metaphor conveys the idea that effective computability is impaired by restrictions that could be removed by infinite methods. Assuming that the undecidability of PA is essentially depending on the finite nature of its computational means, decidability would be restored by the ω-rule. Hypercomputation, the hypothetical realization of infinitary machines through relativistic and quantium models, would thus be capable of breaking the Turing barrier. The speculation is unfounded in principle, apart from issues of physical realizability: The point is that the ω-rule does not cope with all objects entailing the undecidability of PA. As long as the system is consistent, the computational boundary can be established by paradox-like constructions, such as Gödel-Rosser’s and Yablo’s, which are refractory to infinite induction, and do stand as the barrier’s buttresses.

Why Truth-Relativists Should Be Non-conformists Abstract In recent work (“Disagreement, relativism, and doxastic revision”, 2014, Erkenntnis), J. Adam Carter argues that truth-relativism should be compatible with the so-called conformist response to peer disagreement about taste to the effect that subjects should revise their opinions. However, Carter claims that truth-relativism cannot make sense of this response since it cannot make sense of the idea that when two subjects are recognised as epistemic peers, they should acknowledge that they are equally likely to be right about the targeted issue. The main aim of this paper is a modest one: to argue that truth-relativists should not be worried about their alleged incompatibility with conformism for they should be non-conformists.

Giving Up on “the Rest of the Language” Abstract In this essay, the tension that Benacerraf identifies for theories of mathematical truth is used as the vehicle for arguing against a particular desideratum for semantic theories. More specifically, I place in question the desideratum that a semantic theory, provided for some area of discourse, should run in parallel with the semantic theory holding for the rest of the language. The importance of this desideratum is also made clear by means of tracing out the subtle (though significant) implications of its rejection.

Rearming the Slingshot? Abstract Slingshot arguments aim to show that an allegedly non-extensional sentential connective—such as “necessarily (_)” or “the statement that Φ corresponds to the fact that (_)”—is, to the contrary, an extensional sentential connective. Stephen Neale (Mind 104 (416): 761-825, 1995, 2001) argues that a reformulation of Gödel’s slingshot puts pressure on us to adopt a particular view of definite descriptions. I formulate a revised version of the slingshot argument—one that relies on Kaplan’s notion of “dthat.” I aim to show that if Neale’s version of the slingshot argument is successful, then there is another slingshot available, parallel in structure to Neale’s, but independent of definite descriptions. So either (i) there is a version of the slingshot that succeeds independent of any particular theory of descriptions or else (ii) Neale’s slingshot was never threatening to begin with.

Did People in the Middle Ages Know that the Earth Was Flat? Abstract The goal of this paper is to explore the presuppositionality of factive verbs, with special emphasis on the verbs know and regret. The hypothesis put forward here is that the factivity related to know and the factivity related to regretare two different phenomena, as the former is a semantic implication (an entailment) that is licensed by the conventional meaning of know, while the latter is a purely pragmatic phenomenon that arises conversationally. More specifically, it is argued that know is factive in the sense that it both entails and (pragmatically) presupposes p, while regret is factive in the sense that it only (pragmatically) presupposes p. In a recent article, Hazlett (Philosophy and Phenomenological Research, 80(3), 497–522, 2010) shows with authentic examples how know is used non-factively in ordinary language, and he observes in these examples, as he says, “a threat to Factivity.” I argue that non-factive uses of factive verbs, such as know and regret, far from being a threat to factivity, show that, on the one hand, know is ambiguous between a factive and a non-factive sense; on the other hand, in the case of regret, the presupposition of factivity has to be intended as a merely pragmatic implication which can be suspended by the speaker herself.

Why Being Necessary Really Is Not the Same As Being Not Possibly Not Abstract In standard modal logic, □ ≡ ∼◊ ∼ and ◊ ≡ ∼□∼. I will, first, examine why in tense-logic, Arthur Prior thinks that ∼ ◊ ∼ is weaker than □ and ∼ □ ∼ is weaker than ◊. I will, then, examine whether there are similar motivations in modal logic to take ∼ ◊ ∼ to be weaker than □ and ∼ □ ∼ to be weaker than ◊. The upshot will be that, just as certain metaphysical views within the philosophy of time (e.g., Presentism) motivate one to deny the standard tense equivalences, certain metaphysical views within the metaphysics of modality (e.g., Contingentism, nonmodalism) motivate one to deny the standard modal equivalences.

Vargas-Style Revisionism and the Problem of Retributivism Abstract Manuel Vargas advocates a revised understanding of the terms “free will” and “moral responsibility” that eliminates the problematic libertarian commitments inherent to the commonsense understanding of these terms. I argue that in order to make a plausible case for why philosophers ought to adopt his recommendations, Vargas must explain why we ought to retain the retributivist elements that figure prominently in both commonsense views about morality and philosophical discussions concerning free will and moral responsibility. Furthermore, I argue that his revisionist account lacks the resources necessary to accommodate retributivist attitudes and practices.

Approximate Truth, Quasi-Factivity, and Evidence Abstract The main question addressed in this paper is whether some false sentences can constitute evidence for the truth of other propositions. In this paper it is argued that there are good reasons to suspect that at least some false propositions can (at least some times) constitute evidence for the truth of certain other contingent propositions. The paper also introduces a novel condition concerning propositions that constitute evidence that explains a ubiquitous evidential practice and it contains a defense of a particular condition concerning the possession of evidence. The core position adopted here then is that false propositions that are approximately true reports of measurements can constitute evidence for the truth of other propositions. So, it will be argued that evidence is only quasi-factive in this very specific sense.

Intentionality and Realism Abstract In this paper, I argue that how a mind can come to be about an object and how the world is independently of the workings of any mind are inextricably linked. Hence, epistemology, at its most basic, and metaphysics are systematically related. In order to demonstrate the primary thesis of the paper, I first articulate two contrary accounts of the nature of reality and then two contradictory general views of intentionality. I argue that these positions can be combined in only two ways. This argument turns on the impossibility of there being an object that cannot, in principle, be thought of or referred to, so I present reasons for thinking such a thing cannot exist. The upshot is that there are but two intentional-cum-ontological positions, that is, two unified positions regarding how a mind relates to the world and what the world is like in itself. This might be surprising, for one might have thought that the views in the different domains were independent; it is significant, because it shows that views that might have seemed related by mere affinity are, in fact, necessarily conjoined. I conclude by presenting reasons for thinking one of the two intentional-cum-ontological positions is untenable.