Besides pure declarative arguments, whose premises and conclusions are declaratives (“you sinned shamelessly; so you sinned”), and pure imperative arguments, whose premises and conclusions are imperatives (“repent quickly; so repent”), there are mixed-premise arguments, whose premises include both imperatives and declaratives (“if you sinned, repent; you sinned; so repent”), and cross-species arguments, whose premises are declaratives and whose conclusions are imperatives (“you must repent; so repent”) or vice versa (“repent; so you can repent”). I propose a general definition of argument (...) validity: an argument is valid exactly if, necessarily, every fact that sustains its premises also sustains its conclusion, where a fact sustains an imperative exactly if it favors the satisfaction over the violation of the imperative, and a fact sustains a declarative exactly if, necessarily, the declarative is true if the fact exists. I argue that this definition yields as special cases the standard definition of validity for pure declarative arguments and my previously defended definition of validity for pure imperative arguments, and that it yields intuitively acceptable results for mixed-premise and cross-species arguments. (shrink)

Besides pure declarative arguments, whose premises and conclusions are declaratives, and pure imperative arguments, whose premises and conclusions are imperatives, there are mixed-premise arguments, whose premises include both imperatives and declaratives, and cross-species arguments, whose premises are declaratives and whose conclusions are imperatives or vice versa. I propose a general definition of argument validity: an argument is valid exactly if, necessarily, every fact that sustains its premises also sustains its conclusion, where a fact sustains an imperative exactly if it favors (...) the satisfaction over the violation proposition of the imperative, and a fact sustains a declarative exactly if, necessarily, the declarative is true if the fact exists. I argue that this definition yields as special cases the standard definition of validity for pure declarative arguments and my previously defended definition of validity for pure imperative arguments, and that it yields intuitively acceptable results for mixed-premise and cross-species arguments. (shrink)

Philosophers like G.H. von Wright and D. Makinson have pointed to serious challenges regarding the foundations of deontic logic. In this paper, I suggest that to deal successfully with these challenges a reconsideration of the research program of the discipline is useful. Some problems that have troubled this particular field of logical study for decades may disappear or appear more tractable if we view them from the perspective of a language game introduced by D. Lewis involving three characters: the Master, (...) the Slave and the Kibitzer. The adoption of this perspective opens a natural approach to a new layout of the domain of deontic studies. I propose dividing deontic logic into six sub-areas which are distinguished by their focus on the different idioms typical of the individual players, by conceiving the language game as either being static or as dynamic and by the aims of the logical inquiry. What kind of insights the proposed perspective provides is illustrated by an analysis of the so-called Ross paradox—a problem that has troubled deontic logic since its origins and, though it was many times pronounced solved, still keeps coming back ‘alive and kicking’. (shrink)

The status of constructivism as a metaethical or metanormative theory is unclear partly due to the lack of a clear semantics for central normative terms such as ‘reason’ and ‘ought’. In a series of recent papers, Sharon Street has attempted to clarify the central commitments of constructivism by focusing on the idea of a practical point of view and what follows from it. We improve upon the informal understanding provided by Street and attempt to provide a semantics for ‘ought’. Our (...) semantics respects the core intuition of the constructivist that normative claims are made true because of our practical commitments as agents and also reflects the constructivist’s commitment to the centrality of practical deliberation to normative truth. On our view, a normative claim of the form ⌜S ought to ϕ⌝ is true if ϕ is entailed from S’s set of evaluative attitudes. We argue that a virtue of our definition is that it allows us to see precisely what is distinctive about constructivism as opposed to realism and expressivism. (shrink)

Some arguments include imperative clauses. For example: ‘Buy me a drink; you can’t buy me that drink unless you go to the bar; so, go to the bar!’ How should we build a logic that predicts which of these arguments are good? Because imperatives aren’t truth apt and so don’t stand in relations of truth preservation, this technical question gives rise to a foundational one: What would be the subject matter of this logic? I argue that declaratives are used to (...) produce beliefs, imperatives are used to produce intentions, and beliefs and intentions are subject to rational requirements. An argument will strike us as valid when anyone whose mental state satisfies the premises is rationally required to satisfy the conclusion. For example, the above argument reflects the principle that it is irrational not to intend what one takes to be the necessary means to one’s intended ends. I argue that all intuitively good patterns of imperative inference can be explained using off-the-shelf formulations of our rational requirements. I then develop a formal-semantic theory embodying this view that predicts a range of data, including free-choice effects and Ross’s paradox. The resulting theory shows one way that our aspirations to rational agency can be discerned in the patterns of our speech, and is a case study in how the philosophy of language and the philosophy of action can be mutually illuminating. (shrink)

In a series of articles, P. Vranas recently proposed a new imperative logic. The strong and weak inferences of this logic are motivated by an appeal to a strong and weak ‘support by reasons’ that transfers from the premisses of an argument to its conclusion. They also combine nonmonotonic and monotonic reasoning patterns. I show that for any moral agent, Vranas’s proposal can be simplified enormously.

This paper articulates an account of imperatives that sensibly supports the idea of a logic of imperative inferences. We rebuke common objections to the very possibility of such a logic, from a perspective based on recent linguistic work on the morphosyntax of imperatives. Specifically, we develop the notion that the content of an imperative sentence includes both a force operator alongside an imperational content to which the force applies. We further argue that this account of the content of imperatives constitutes (...) a plausible and flexible framework to develop a logic of imperative by examining a number of reconstructions of this idea using semantical analogs of widespread modal semantics. After studying the performance of those approaches, we conclude that progress in imperative logic has been hindered by the failure to adopt conflict-tolerant and resource-sensitive semantics, but suggest that such considerations can be incorporated in this flexible framework. Finally, we also propose a simple account of the difference between operators applying to the content of imperatives and imperative operators, in a way that sheds light on some of the issues underlying the usual antinomies. (shrink)

In this paper I will develop a view about the semantics of imperatives, which I term Modal Noncognitivism, on which imperatives might be said to have truth conditions (dispositionally, anyway), but on which it does not make sense to see them as expressing propositions (hence does not make sense to ascribe to them truth or falsity). This view stands against “Cognitivist” accounts of the semantics of imperatives, on which imperatives are claimed to express propositions, which are then enlisted in explanations (...) of the relevant logico-semantic phenomena. It also stands against the major competitors to Cognitivist accounts—all of which are non-truth-conditional and, as a result, fail to provide satisfying explanations of the fundamental semantic characteristics of imperatives (or so I argue). The view of imperatives I defend here improves on various treatments of imperatives on the market in giving an empirically and theoretically adequate account of their semantics and logic. It yields explanations of a wide range of semantic and logical phenomena about imperatives—explanations that are, I argue, at least as satisfying as the sorts of explanations of semantic and logical phenomena familiar from truth-conditional semantics. But it accomplishes this while defending the notion—which is, I argue, substantially correct—that imperatives could not have propositions, or truth conditions, as their meanings. (shrink)

I defend the view that linguistic meaning is a relation borne by an expression to a type of speech act, and that this relation holds in virtue of our overlapping communicative dispositions, and not in virtue of linguistic conventions. I argue that this theory gives the right account of the semantics–pragmatics interface and the best-available semantics for non-declarative clauses, and show that it allows for the construction of a rigorous compositional semantic theory with greater explanatory power than both truth-conditional and (...) dynamic semantics. (shrink)

My dissertation addresses the question "do desires provide reasons?" I present two independent lines of argument in support of the conclusion that they do not. The first line of argument emerges from the way I circumscribe the concept of a desire. Complications aside, I conceive of a desire as a member of a family of attitudes that have imperative content, understood as content that displays doability-conditions rather than truth-conditions. Moreover, I hold that an attitude may provide reasons only if it (...) has truth-evaluable content. Insofar as desires lack truth-evaluable content, I hold that the content of a desire has the wrong kind of logical structure to provide reasons. My second line of argument claims that even if a desire did have truth-evaluable content, it would not follow that desires provide reasons. This is because a desire has no more rational significance than a guess or coin-flip. My argument relies on what I call the non-substitutability principle, the thesis that (all things being equal) one cannot substitute something that lacks rational significance, relative to some attitude, A, for something that has rational significance, relative to A, and leave the rational standing of A unchanged. For example, one cannot substitute the guess that P (i.e., something that lacks rational significance relative to the belief that P) for the perception that P (i.e., something that is rationally significant relative to the belief that P) without altering the rational standing of the belief. I argue that when the non-substitutability principle is applied to a desire that gives rise to an intention, it turns out that one can always substitute a guess or coin-flip (i.e., something that lacks rational significance relative to the intention) for the desire, without altering the rational standing of the intention. I take this to show that desires are not rationally significant relative to the intentions to which they give. (shrink)