There is a renewed debate about modus ponens. Strikingly, the recent counterexamples in Cantwell, Dreier and MacFarlane and Kolodny are generated by restricted readings of the ‘if’-clause. Moreover, it can be argued on general grounds that the restrictor view of conditionals developed in Kratzer and Lewis leads to counterexamples to modus ponens. This paper provides a careful analysis of modus ponens within the framework of the restrictor view. Despite appearances to the contrary, there is a robust sense in which modus (...) ponens is valid, owing to the fact that conditionals do not only allow for restricted readings but have bare interpretations, too. (shrink)

You are irrational when you are akratic. On this point most agree. Despite this agreement, there is a tremendous amount of disagreement about what the correct explanation of this data is. Narrow-scopers think that the correct explanation is that you are violating a narrow-scope conditional requirement. You lack an intention to x that you are required to have given the fact that you believe you ought to x. Wide-scopers disagree. They think that a conditional you are required to make true (...) is false. You aren’t required to have any particular attitudes. You’re just required to intend to x or not believe you ought to x. Wide-scope accounts are symmetrical insofar as they predict that you are complying with the relevant requirement just so long as the relevant conditional is true. Some narrow-scopers object to this symmetry. However, there is disagreement about why the symmetry is objectionable. This has led wide-scopers to defend their view against a number of different symmetry objections. I think their defenses in the face of these objections are, on the whole, plausible. Unfortunately for them, they aren’t defending their view against the best version of the objection. In this paper I will show that there is a symmetry objection to wide-scope accounts that both hasn’t been responded to and is a serious problem for wide-scope accounts. Moreover, my version of the objection will allow us to see that there is at least one narrow-scope view that has been seriously underappreciated in the literature. (shrink)

You are irrational when you are akratic. On this point most agree. Despite this agreement, there is a tremendous amount of disagreement about what the correct explanation of this data is. Narrow-scopers think that the correct explanation is that you are violating a narrow-scope conditional requirement. You lack an intention to x that you are required to have given the fact that you believe you ought to x. Wide-scopers disagree. They think that a conditional you are required to make true (...) is false. You aren’t required to have any particular attitudes. You’re just required to intend to x or not believe you ought to x. Wide-scope accounts are symmetrical insofar as they predict that you are complying with the relevant requirement just so long as the relevant conditional is true. Some narrow-scopers object to this symmetry. However, there is disagreement about why the symmetry is objectionable. This has led wide-scopers to defend their view against a number of different symmetry objections. I think their defenses in the face of these objections are, on the whole, plausible. Unfortunately for them, they aren’t defending their view against the best version of the objection. In this paper I will show that there is a symmetry objection to wide-scope accounts that both hasn’t been responded to and is a serious problem for wide-scope accounts. Moreover, my version of the objection will allow us to see that there is at least one narrow-scope view that has been seriously underappreciated in the literature. (shrink)

This paper defends the permissibility solution to the lottery paradox against an objection by Anna-Maria Asunta Eder. Eder argues that the permissibility solution should also be applicable to the preface paradox, but conflicts with a plausible principle about epistemic permissions when so applied. This paper replies by first criticizing Eder’s considerations in defense of her principle; in particular, it argues that the plausibility of her principle is to a large extent parasitic on the spurious plausibility of the principle of factual (...) detachment. The paper then presents a direct argument against Eder’s principle, which shows that her principle conflicts with a Pareto-style condition on permissible belief. (shrink)

Some intuitive normative principles raise vexing 'detaching problems' by their failure to license modus ponens. I examine three such principles (a self-reliance principle and two different instrumental principles) and recent stategies employed to resolve their detaching problems. I show that solving these problems necessitates postulating an indefinitely large number of senses for 'ought'. The semantics for 'ought' that is standard in linguistics offers a unifying strategy for solving these problems, but I argue that an alternative approach combining an end-relational theory (...) of normativity with a comparative probabilistic semantics for 'ought' provides a more satisfactory solution. (shrink)

This paper advances a reductive semantics for ‘ought’ and a naturalistic theory of normativity. It gives a unified analysis of predictive, instrumental, and categorical uses of ‘ought’: the predictive ‘ought’ is basic, and is interpreted in terms of probability. Instrumental ‘oughts’ are analyzed as predictive ‘oughts’ occurring under an ‘in order that’ modifer (the end-relational theory). The theory is then extended to categorical uses of ‘ought’: it is argued that they are special rhetorical uses of the instrumental ‘ought’. Plausible conversational (...) principles explain how this end-relational ‘ought’ can perform the expressive functions of the moral ‘ought’. The notion of an ‘ought-simpliciter’ is also discussed. (shrink)

Ethical theorists often assume that the verb ‘ought’ means roughly ‘has an obligation’; however, this assumption is belied by the diversity of ‘flavours’ of ought-sentences in English. A natural response is that ‘ought’ is ambiguous. However, this response is incompatible with the standard treatment of ‘ought’ by theoretical semanticists, who classify ‘ought’ as a member of the family of modal verbs, which are treated uniformly as operators. To many ethical theorists, however, this popular treatment in linguistics seems to elide an (...) important distinction between agential and non-agential ought-statements. The thought is that ‘ought’ must have at least two senses, one implicating agency and connected to obligations, and another covering other uses. In this paper, I pursue some resolution of this tension between semantic theory and ethical theory with respect to the meaning of ‘ought’. To this end, I consider what I believe to be the most linguistically sophisticated argument for the view that the word ‘ought’ is ambiguous between agential and non-agential senses. This argument, due to Mark Schroeder, is instructive but based on a false claim about the syntax of agential ought-sentences—or so I attempt to show by first situating Schroeder's argument in its proper linguistic background and then discussing some syntactic evidence that he fails to appreciate. Then, I use the failure of this argument to motivate some more general reflections on how the standard treatment of ‘ought’ by theoretical semanticists might be refined in the light of the distinction important to ethical theory between agential and non-agential ought-statements, but also on how ethical theory might benefit from more careful study of the dominant treatment of modals as operators in theoretical semantics. (shrink)

If modus ponens is valid, then you should take up smoking.

This entry is composed of three sections. In §1, we survey debates about what structural rationality is, including the emergence of the concept in the contemporary literature, its key characteristics, its relationship to substantive rationality, its paradigm instances, and the questions of whether these instances are unified and, if so, how. In §2, we turn to the debate about structural requirements of rationality – including controversies about whether they are “wide-scope” or “narrow-scope”, synchronic or diachronic, and whether they govern processes (...) or states; as well as examining various forms of skepticism about structural requirements of rationality. In §3, we turn to the debate about the normative significance of structural rationality, surveying central challenges for the view that structural rationality is normatively significant and the theoretical options that arise in light of these challenges. (shrink)

Normative concepts have a special taste, which many consider to be proof that they cannot be reductively analyzed into entirely nonnormative components. This paper demonstrates that at least some intuitively normative concepts can be reductively analyzed. I focus on so-called ‘hypothetical imperatives’ or ‘anankastic conditionals’, and show that the availability of normative readings of conditionals is determined by features of grammar, specifically features of tense. Properly interpreted, these grammatical features suggest that these deontic modals are analyzable in terms of conditional (...) necessity with a certain temporal structure. (shrink)