A selection function based semantics is offered for the 'can' of ability based on the idea that 'John can run a four minute mile' is true iff John would do so under the right conditions, meaning that he would do so under at least one appropriately chosen test condition. Completeness is proved for an axiom system and semantics based on this idea, and the logic turns out to be interestingly different from any standard system of modal logic.

Statements about the future are central in everyday conversation and reasoning. How should we understand their meaning? The received view among philosophers treats will as a tense: in ‘Cynthia will pass her exam’, will shifts the reference time forward. Linguists, however, have produced substantial evidence for the view that will is a modal, on a par with must and would. The different accounts are designed to satisfy different theoretical constraints, apparently pulling in opposite directions. We show that these constraints are (...) jointly satisfied by a novel modal account of will. On this account, will is a modal but doesn't work as a quantifier over worlds. Rather, the meaning of will involves a selection function similar to the one used by Stalnaker in his semantics for conditionals. The resulting theory yields a plausible semantics and logic for will and vindicates our intuitive views about the attitudes that rational agents should have towards future-directed contents. (shrink)

I motivate and characterize an intensional semantics for ‘ought’ on which it does not behave as a universal quantifier over possibilities. My motivational argument centers on taking at face value some standard challenges to the quantificational semantics, especially to the idea that ‘ought’-sentences satisfy the principle of Inheritance. I argue that standard pragmatic approaches to these puzzles are either not sufficiently detailed or unconvincing.

Do logically valid arguments necessarily preserve truth? Certain inferences involving informational modal operators and indicative conditionals suggest that truth preservation and good deductive argument come apart. Given this split, I recommend an alternative to the standard truth preservation view of logic on which validity and good deductive argument coincide: logic is a descriptive science that is fundamentally concerned not with the preservation of truth, but with the preservation of structural features of information. Along the way, I defend modus ponens for (...) the indicative against an attack by Kolodny and MacFarlane, and I present a new proof system, Info, appropriate to this informational view. (shrink)

Many of us are tempted by the thought that the future is open, whereas the past is not. The future might unfold one way, or it might unfold another; but the past, having occurred, is now settled. In previous work we presented an account of what openness consists in: roughly, that the openness of the future is a matter of it being metaphysically indeterminate how things will turn out to be. We were previously concerned merely with presenting the view and (...) exploring its consequences; we did not attempt to argue for it over rival accounts. That is what we will aim to do in this paper. (shrink)

The book presents a new logical framework to capture the meaning of sentences in conversation. It is based on a richer notion of meaning than traditional approaches, and allows for an integrated treatment of statements and questions. The first part of the book presents the framework in detail, while the second demonstrates its many benefits.

Surveys and extens work that has been done in the past two years on 'tense logic' and is a sequel to the author's book, Time and Modality.

But Findlay's remark, like so much that has been written on the subject of time in the present century, was provoked in the first place by McTaggart's ...

Epistemic modal operators give rise to something very like, but also very unlike, Moore's paradox. I set out the puzzling phenomena, explain why a standard relational semantics for these operators cannot handle them, and recommend an alternative semantics. A pragmatics appropriate to the semantics is developed and interactions between the semantics, the pragmatics, and the definition of consequence are investigated. The semantics is then extended to probability operators. Some problems and prospects for probabilistic representations of content and context are explored.

The received wisdom on ability modals is that they differ from their epistemic and deontic cousins in what inferences they license and better receive a universal or conditional analysis instead of an existential one. The goal of this paper is to sharpen the empirical picture about the semantics of ability modals, and to propose an analysis that explains what makes the can of ability so special but that also preserves the crucial idea that all uses of can share a common (...) lexical semantics. The resulting framework combines tools and techniques from dynamic and inquisitive semantics with insights from the literature of the role of agency in deontic logic. It explains not only why the can of ability, while essentially being an existential modal operator, sometimes resists distribution over disjunction and interacts with its duals in particular and hitherto unnoticed ways, but also has a tendency to license free choice inferences. (shrink)

The compositional semantics of sentences like Only mammals give live birth and The flag flies only if the Queen is home is a tough problem. Evidence is presented to show that only here is modifying an underlying proposition (its ‘prejacent’). After discussing the semantics of only, the question of the proper interpretation of the prejacent is explored. It would be nice if the prejacent could be analyzed as having existential quantificational force. But that is difficult to maintain, since the prejacent (...) structures when encountered on their own are naturally read as having a lawlike flavor, which in many analyses is attributed to the semantics of implicit operators alleged to be present in them. In the end, an analysis is presented which attributes some very particular properties to these operators and thereby succeeds in providing the target sentences with intuitively adequate interpretations. These complex constructions can therefore be used as a probe into the nature of implicit quantification in natural language. (shrink)

This paper begins with a discussion ofcumulativity (e.g., ‘P(a) & P(b) implies P(a+b)’), formalized using a verb phrase operator. Next, the meanings of distributivity markers such aseach and non-distributivity indicators such astogether are considered. An existing analysis ofeach in terms of quantification over parts of a plurality is adopted. However,together is problematic, for it involves a cancellation or negation of the quantification associated witheach. (The four boys together owned exactly three cars could not be true if each of the boys (...) owned three cars, though the same sentence withouttogether could be.) A refinement of this idea of negated quantification over parts is proposed as an analysis for non-distributivity operators. It is then worked out in the system described in Cooper (1983), in which positive and negative extensions are assigned. Presuppositions connected with plural reference are considered at this point as well. Finally, the cumulativity operator is argued to be quantificational and therefore sensitive to contextual domain selection. This context sensitivity is claimed to be the source of distributive readings that appear in the absence of modifiers likeeach and non-distributive or collective readings that arise withouttogether. (shrink)

Natural language conditionals seem to be subject to three logical requirements: they invalidate Antecedent Strengthening, they validate so-called Simplification of Disjunctive Antecedents, and they allow for the replacement of logically equivalent clauses in antecedent position. Unfortunately, these requirements are jointly inconsistent. Conservative solutions to the puzzle drop Simplification, treating it as a pragmatic inference. I show that pragmatic accounts of Simplification fail, and develop a truthmaker semantics for conditionals that captures all the relevant data. Differently from existing truthmaker semantics, my (...) semantics extends, rather than replaces, standard possible worlds semantics. The main innovation is the notion of a truthmaker in play: this notion is cognitive, rather than metaphysical, and can be defined in a purely syntactic way. (shrink)

This essay uses a puzzle about assertion and time to explore the pragmatics, semantics, and epistemology of future discourse. The puzzle concerns cases in which a subject is in a position to say, at an initial time t, that it will be that ϕ, but is not in a position to say, at a later time t′, that it is or was that ϕ, despite not losing or gaining any relevant evidence between t and t′. We consider a number of (...) approaches to the puzzle and defend the view that subjects in these cases lose knowledge simply by moving through time. (shrink)

This essay proposes a new theory of agentive modals: ability modals and their duals, compulsion modals. After criticizing existing approaches—the existential quantificational analysis, the universal quantificational analysis, and the conditional analysis—it presents a new account that builds on both the existential and conditional analyses. On this account, the act conditional analysis, a sentence like ‘John can swim across the river’ says that there is some practically available action that is such that if John tries to do it, he swims across (...) the river. The essay argues that the act conditional analysis avoids the problems faced by existing accounts of agentive modality and shows how the act conditional analysis can be extended to an account of generic agentive modal claims. The upshot is a new vantage point on the role of agentive modal ascriptions in practical discourse: ability ascriptions serve as a kind of hypothetical guarantee, and compulsion ascriptions as a kind of nonhypothetical guarantee. (shrink)

Accounts of ability in the philosophical literature have tended to be modal ones: claims about an agent’s abilities are understood in terms of what she does in certain non-actual scenarios. In contrast, a prominent account of ability ascriptions in the recent semantics literature appeals to genericity: claims about an agent’s abilities are understood in terms of what she generally manages to do. The latter account resolves some long-standing problems for modal accounts, but encounters problems of its own. I propose a (...) hybrid view, on which ability involves both a modal and a generic element. (shrink)

If it is not now determined whether there will be a sea battle tomorrow, can an assertion that there will be one be true? The problem has persisted because there are compelling arguments on both sides. If there are objectively possible futures which would make the prediction true and others which would make it false, symmetry considerations seem to forbid counting it either true or false. Yet if we think about how we would assess the prediction tomorrow, when a sea (...) battle is raging (or not), it seems we must assign the utterance a definite truth-value. I argue that both arguments must be given their due, and that this requires relativizing utterance-truth to a context of assessment. I show how this relativization can be handled in a rigorous formal semantics, and I argue that we can make coherent sense of assertion without assuming that utterances have their truth-values absolutely. (shrink)

In this paper I offer an account of the meaning of must and can within the framework of possible worlds semantics. The paper consists of two parts: the first argues for a relative concept of modality underlying modal words like must and can in natural language. I give preliminary definitions of the meaning of these words which are formulated in terms of logical consequence and compatibility, respectively. The second part discusses one kind of insufficiency in the meaning definitions given in (...) the first part, which arise from the ex falso quodlibet paradox of logical consequence. In stepwise fashion, I make an attempt to avoid most of the consequences of this paradox for the meaning definitions of must and can. (shrink)

John Horty effectively develops deontic logic (the logic of ethical concepts like obligation and permission) against the background of a formal theory of agency. He incorporates certain elements of decision theory to set out a new deontic account of what agents ought to do under various conditions over extended periods of time. Offering a conceptual rather than technical emphasis, Horty's framework allows a number of recent issues from moral theory to be set out clearly and discussed from a uniform point (...) of view. (shrink)

Options and the subjective ought Content Type Journal Article Pages 1-18 DOI 10.1007/s11098-012-9880-0 Authors Brian Hedden, Department of Linguistics and Philosophy, Massachusetts Institute of Technology, Cambridge, MA, USA Journal Philosophical Studies Online ISSN 1573-0883 Print ISSN 0031-8116.

The Free Choice effect—whereby \\) seems to entail both \ and \—has traditionally been characterized as a phenomenon affecting the deontic modal ‘may’. This paper presents an extension of the semantic account of free choice defended by Fusco to the agentive modal ‘can’, the ‘can’ which, intuitively, describes an agent’s powers. On this account, free choice is a nonspecific de re phenomenon that—unlike typical cases—affects disjunction. I begin by sketching a model of inexact ability, which grounds a modal approach to (...) agency in a Williamson -style margin of error. A classical propositional semantics combined with this framework can reflect the intuitions highlighted by Kenny ’s dartboard cases, as well as the counterexamples to simple conditional views recently discussed by Mandelkern et al.. In Section 3, I turn to an independently motivated actual-world-sensitive account of disjunction, and show how it extends free choice inferences into an object language for propositional modal logic. (shrink)

I develop a basic theory of content within the framework of truthmaker semantics and, in the second part, consider some of the applications to subject matter, common content, logical subtraction and ground.

In this theory, both adverbs and heads, which encode the functional notions of the clause, are ordered in a rigid sequence.

This note identifies and corrects some problems in developments of the thesis that predictive expressions, such as English "will", are modals. I contribute a new argument supporting Cariani and Santorio's recent claim that predictive expressions are non-quantificational modals. At the same time, I improve on their selectional semantics by fixing an important bug. Finally, I show that there are benefits to be reaped by integrating the selection semantics framework with standard ideas about the future orientation of modals.

This paper develops a semantic solution to the puzzle of Free Choice permission. The paper begins with a battery of impossibility results showing that Free Choice is in tension with a variety of classical principles, including Disjunction Introduction and the Law of Excluded Middle. Most interestingly, Free Choice appears incompatible with a principle concerning the behavior of Free Choice under negation, Double Prohibition, which says that Mary can’t have soup or salad implies Mary can’t have soup and Mary can’t have (...) salad. Alonso-Ovalle 2006 and others have appealed to Double Prohibition to motivate pragmatic accounts of Free Choice. Aher 2012, Aloni 2018, and others have developed semantic accounts of Free Choice that also explain Double Prohibition. -/- This paper offers a new semantic analysis of Free Choice designed to handle the full range of impossibility results involved in Free Choice. The paper develops the hypothesis that Free Choice is a homogeneity effect. The claim possibly A or B is defined only when A and B are homogenous with respect to their modal status, either both possible or both impossible. Paired with a notion of entailment that is sensitive to definedness conditions, this theory validates Free Choice while retaining a wide variety of classical principles except for the transitivity of entailment. The homogeneity hypothesis is implemented in two different ways, homogeneous alternative semantics and homogeneous dynamic semantics, with interestingly different consequences. (shrink)

This paper proposes a formalization of ability that is motivated in part by linguistic considerations and by the philosophical literature in action theory and the logic of ability, but that is also meant to match well with planning formalisms, and so to provide an account of the role of ability in practical reasoning. Some of the philosophical literature concerning ability, and in particular [Austin, 1956], suggests that some ways of talking about ability are context-dependent. I propose a way of formalizing (...) this dependency. (shrink)