The subjective deontic "ought" generates counterexamples to classical inference rules like modus ponens. It also conflicts with the orthodox view about modals and conditionals in natural language semantics. Most accounts of the subjective ought build substantive and unattractive normative assumptions into the semantics of the modal. I sketch a general semantic account, along with a metasemantic story about the context sensitivity of information-sensitive operators.

Michael Ridge presents an original expressivist theory of normative judgments--Ecumenical Expressivism--which offers distinctive treatments of key problems in metaethics, semantics, and practical reasoning. He argues that normative judgments are hybrid states partly constituted by ordinary beliefs and partly constituted by desire-like states.

Every adequate semantics for conditionals and deontic ought must offer a solution to the miners paradox about conditional obligations. Kolodny and MacFarlane have recently argued that such a semantics must reject the validity of modus ponens. I demonstrate that rejecting the validity of modus ponens is inessential for an adequate solution to the paradox.

We investigate a basic probabilistic dynamic semantics for a fragment containing conditionals, probability operators, modals, and attitude verbs, with the aim of shedding light on the prospects for adding probabilistic structure to models of the conversational common ground.

Discussions about the meaning of the word “ought” are pulled in two apparently competing directions. First, in ethical theory this word is used in the paradigmatic statement of ethical principles and conclusions about what some agent is obligated to do. This leads some ethical theorists to claim that the word “ought” describes a real relation, roughly, of being obligated to (realism) or expresses some non-cognitive attitude toward agents acting in certain ways (expressivism). Second, in theoretical linguistics this word is classified (...) as a modal auxiliary verb alongside words like “might,” “may,” “can,” “must,” etc. This leads some theoretical linguists to claim that the word “ought” is a weak necessity modal, which can be modeled with universal quantification over a restricted set of possible worlds. This chapter seeks some resolution of this tension by showing how versions of realism and expressivism can be modified in light of the best semantics of “ought” as a weak necessity modal. In addition, the chapter explains how this semantics might point to a third view—inferentialism—that accounts for the meaning of “ought” not in terms of what relation it describes, nor in terms of what attitude it expresses, but rather in terms of its inferential role. (shrink)

This is a study in the meaning of natural language probability operators, sentential operators such as probably and likely. We ask what sort of formal structure is required to model the logic and semantics of these operators. Along the way we investigate their deep connections to indicative conditionals and epistemic modals, probe their scalar structure, observe their sensitivity to contex- tually salient contrasts, and explore some of their scopal idiosyncrasies.

This chapter discusses three puzzles about practical conditionals and inferences and shows how the flexible, contextualist semantic framework for “ought”. The chapter develops elsewhere resolves all three puzzles more satisfactorily than any of its three most prominent rivals, the relativist account of Niko Kolodny and John MacFarlane, the wide-scoping account of John Broome, and the “trying on” account of James Dreier. The chapter first introduces the puzzle cases and six desiderata for their solutions, and then shows how only flexible contextualism (...) about “ought” is able to resolve each while satisfying all six desiderata. (shrink)

I develop a conception of expressivism according to which it is chiefly a pragmatic thesis about some fragment of discourse, one imposing certain constraints on semantics. The first half of the paper uses credal expressivism about the language of probability as a stalking-horse for this purpose. The second half turns to the question of how one might frame an analogous form of expressivism about the language of deontic modality. Here I offer a preliminary comparison of two expressivist lines. The first, (...) expectation expressivism, looks again to Bayesian modelling for inspiration: it glosses deontically modal language as characteristically serving to express decision-theoretic expectation (expected utility). The second, plan expressivism, develops the idea (due to Gibbard 2003) that this language serves to express 'plan-laden' states of belief. In the process of comparing the views, I show how to incorporate Gibbard's modelling ideas into a compositional semantics for attitudes and modals, filling a lacuna in the account. I close with the question whether and how plan expressivism might be developed with expectation-like structure. (shrink)

We discuss the semantic significance of a puzzle concerning ‘ought’ and conditionals recently discussed by Kolodny and MacFarlane. We argue that the puzzle is problematic for the standard Kratzer-style analysis of modality. In Kratzer’s semantics, modals are evaluated relative to a pair of conversational backgrounds. We show that there is no sensible way of assigning values to these conversational backgrounds so as to derive all of the intuitions in Kolodny and MacFarlane’s case. We show that the appropriate verdicts can be (...) derived by extending Kratzer’s framework to feature a third conversational background and claiming that the relevant reading of ‘ought’ is sensitive to this parameter. (shrink)

Causal decision theory attends to probabilities used to obtain an option's expected utility but for completeness should also attend to utilities of possible outcomes. A suitable formula for an option's expected utility uses a certain type of conditional utility.

This book makes a significant contribution to the standard decision theory, that is, the theory of choice built around the principle of maximizing expected utility, both to its causal version and to the more traditional noncausal approach. The author’s success in clarifying the foundations of the standard decision theory in general, and causal decision theory in particular, also makes the book uniquely suitable for a person whose research in philosophy has led her to want to learn about contemporary decision theory. (...) The book presupposes some mathematical sophistication, and it contains more philosophical and mathematical argumentation per page than may be suitable for an undergraduate level course; but it stands out as an ideal textbook for a graduate-level course focused on the foundations of the standard decision theory. (shrink)