If you ought to perform a certain act, and some other action is a necessary means for you to perform that act, then you ought to perform that other action as well – or so it seems plausible to say. This transmission principle is of both practical and theoretical significance. The aim of this paper is to defend this principle against a number of recent objections, which (as I show) are all based on core assumptions of the view called actualism. (...) I reject actualism, provide an alternative explanation of its plausible features, and present an independent argument for the transmission principle. (shrink)

The book concerns what I take to be the least controversial normative principle concerning action: you ought to perform your best option—best, that is, in terms of whatever ultimately matters. The book sets aside the question of what ultimately matters so as to focus on more basic issues, such as: What are our options? Do I have the option of typing out the cure for cancer if that’s what I would in fact do if I had the right intentions at (...) the right times (e.g., the intention to type the letter T at t1, the intention to type the letter H at t2, the intention to type the letter E at t3, etc.)? If I can’t form intentions voluntarily, does that mean that I don’t have the option of forming the intention that I ought to form? Which options do we assess directly in terms of their own goodness and which do we assess in terms of their relations to the goodness of other options? What do we hold fixed when assessing how good an option is? Do we, for instance, hold fixed the agent’s future beliefs, desires, and intentions? And do we hold fixed the agent’s predictable future misbehavior? Lastly, how do the things that ultimately matter determine the goodness of an option? If one of the things that ultimately matters in determining the goodness of an option is that the option doesn’t involve violating anyone’s rights, do we evaluate the option itself in terms of whether it involves violating anyone’s rights or do we evaluate the option’s prospect in terms of this and then the option in terms of its prospect? And what if there is indeterminacy or uncertainty with regards to whether an option would involve violating someone’s rights? (shrink)

This paper presents a short survey of recent developments in stit theories, with an emphasis on combinations of stit and deontic logic, and those of stit and epistemic logic.

This paper focuses on the interaction of reasons and argues that reasons for an action may transmit to the necessary means of that action. Analyzing exactly how this phenomenon may be captured by principles governing normative transmission has proved an intricate task in recent years. In this paper, I assess three formulations focusing on normative transmission and necessary means: Ought Necessity, Strong Necessity, and Weak Necessity. My focus is on responding to two of the main objections raised against normative transmission (...) for necessary means, in that they seem to give us reasons for buying tickets to plays we have no intention of seeing and that the principles give us the wrong result when the means are necessary but not sufficient. Even though these objections have been discussed previously, the counterarguments have so far relied on rejecting premises that the proponents of these objections are unlikely to concede. In this paper, I show how we may answer the objections in a way more likely to convince proponents of the objections. The result is an argument for a key aspect when it comes to understanding how reasons and ends-means normativity function. Normative transmission from ends to necessary means is not only interesting at the structural level, it is also possible to argue that it has implications for areas as diverse as philosophy of rationality, political philosophy and applied ethics. (shrink)

Richard Rowland, 1–16) defends the following principle: if we must suspend judgement about whether it is permissible for us to φ, then it is not permissible for us to φ. He calls this the Epistemic → Metaphysical principle. This paper considers two challenges to this principle. First, assuming that both conciliationism and EM are true, then in cases where you and your epistemic peers disagree on both the permissibility of φ-ing and the permissibility of refraining from φ-ing, neither φ-ing nor (...) refraining from φ-ing would be permissible. Thus, the view entails that moral dilemmas, which many regard as impossible, are possible. Second, EM is in conflict with the Principle of Decisive Reasons, 760–782). While EM implies that you may be obligated to φ when it is not permissible for you to believe that you ought to φ, the Principle of Decisive Reasons implies that you ought to φ only if it is permissible for you to believe that you ought to φ. Given those two challenges, I conclude that EM should be rejected. (shrink)

I argue that given standard deontic logic, wide-scope rational requirements entail narrow-scope rational requirements. In particular, the widely-embraced Enkratic Principle entails that if a particular combination of attitudes is rationally forbidden, it is also rationally forbidden to believe that that combination of attitudes is required.

On admet en général qu’il y a deux sortes de concepts normatifs : les concepts évaluatifs, comme bon, et les concepts déontiques, comme devoir. La question que soulève cette distinction est celle de savoir comment il est possible d’affirmer que les concepts évaluatifs sont normatifs. En effet, comme les concepts déontiques semblent constituer le coeur du domaine normatif, plus le fossé entre les deux sortes de concepts est grand, moins il paraîtra plausible d’affirmer que les concepts évaluatifs sont normatifs. Après (...) avoir présenté les différences principales entre les concepts évaluatifs et les concepts déontiques, et montré qu’il y a plus qu’une différence superficielle entre les deux sortes de concepts, j’examinerai la question de la normativité des concepts évaluatifs. Il deviendra apparent que même s’il s’agit de concepts ayant des fonctions différentes, il existe un grand nombre de relations entre les concepts évaluatifs, d’une part, et les concepts de devoir et de raison, d’autre part.It is generally accepted that there are two sorts of normative concepts : evaluative concepts, such as good, and deontic concepts, such as ought. The question that is raised by this distinction is how it is possible to claim that evaluative concepts are normative. As deontic concepts appear to be at the heart of normativity, the more there is a gap between evaluative and deontic concepts, the less it appears plausible to say that evaluative concepts are normative. After having presented the main differences between evaluative and deontic concepts, and shown that there is more than a superficial difference between the two sorts of concepts, the paper turns to the question of the normativitity of evaluative concepts. It will become clear that even if these concepts have different functions, there are a great many ties between evaluative concepts, on the one hand, and the concepts of ought and of reason, on the other hand. (shrink)

Many philosophers argue that the error theory should be rejected because it is incompatible with standard deontic logic and semantics. We argue that such formal objections to the theory fail. Our discussion has two upshots. First, it increases the dialectical weight that must be borne by objections to the error theory that target its content rather than its form. Second, it shows that standard deontic logic and semantics should be revised.

The Aristotelian square of oppositions is a well-known diagram in logic and linguistics. In recent years, several extensions of the square have been discovered. However, these extensions have failed to become as widely known as the square. In this paper we argue that there is indeed a fundamental difference between the square and its extensions, viz., a difference in informativity. To do this, we distinguish between concrete Aristotelian diagrams and, on a more abstract level, the Aristotelian geometry. We then introduce (...) two new logical geometries, and develop a formal, well-motivated account of their informativity. This enables us to show that the square is strictly more informative than many of the more complex diagrams. (shrink)

Titelbaum Oxford studies in epistemology, 2015) has recently argued that the Enkratic Principle is incompatible with the view that rational belief is sensitive to higher-order defeat. That is to say, if it cannot be rational to have akratic beliefs of the form “p, but I shouldn’t believe that p,” then rational beliefs cannot be defeated by higher-order evidence, which indicates that they are irrational. In this paper, I distinguish two ways of understanding Titelbaum’s argument, and argue that neither version is (...) sound. The first version can be shown to rest on a subtle, but crucial, misconstrual of the Enkratic Principle. The second version can be resisted through careful consideration of cases of higher-order defeat. The upshot is that proponents of the Enkratic Principle are free to maintain that rational belief is sensitive to higher-order defeat. (shrink)

This paper has two aims: it develops and defends a fully-fledged account of the epistemic normativity of conjecture it goes sharply against orthodoxy, in arguing that conjecture is epistemically more demanding than assertion. According to the view defended here, one’s conjecture that p is permissible only if one knows that one has warrant, but not sufficient warrant to believe that p. I argue for my account on three independent grounds: the Bach and Harnish account of the nature of communicative speech (...) acts, the plausible normative relation between assertion and other constatives, and the normativity of belief in conjunction with constatives’ epistemic function. (shrink)

One very popular assumption in the epistemological literature is that belief and assertion are governed by one and the same epistemic norm. This paper challenges this claim. Extant arguments in defence of the view are scrutinized and found to rest on value-theoretic inaccuracies. First, the belief-assertion parallel is shown to lack the needed normative strength. Second, I argue that the claim that assertion inherits the norm of belief in virtue of being an expression thereof rests on a failed instance of (...) deontic transmission. Third, the inheritance argument from the norm for action is proven guilty of deontic equivocation. Last but not least, it is argued that, on a functionalist normative picture, assertion and belief are governed by different epistemic norms, in virtue of serving different epistemic functions. (shrink)

RESUMO De acordo com a teoria das funções de verdade, a verdade/falsidade de uma proposição é computável a partir da verdade/falsidade das suas proposições “internas”: para cada proposição há uma função entre valores de verdade. Aplicada a proposições modais, origina a semântica dos mundos possíveis e, aplicada a proposições normativas, origina uma semântica que reduz os conceitos normativos aos conceitos modais, a semântica modal. Esta redução fica posta em questão com a existência dos chamados ‘paradoxos da lógica deôntica’. Estes não (...) podem ser vistos como meras anomalias, mas devem ser vistos como indícios da incorreção da semântica modal. Em todos eles, a regra da necessitação, assim como o axioma da distribuição, “não batem certo”. Não obstante, o cumprimento/incumprimento das normas já é computável a partir da verdade/falsidade das proposições que expressam os estados de coisas devidos. ABSTRACT According to the theory of truth-functions the truth/falsehood of a proposition is computable from the truth/falsehood of its “internal” propositions: for each proposition there is a function between truth values. Possible world semantics arises from the application of that theory to modal propositions; modal semantics - the reduction of normative concepts to modal concepts - arises from its application to normative propositions. But the ‘paradoxes of deontic logic’, as they are called, undermine such reduction: they cannot be seen as mere anomalies but instead as evidence for the wrongness of modal semantics. In all these paradoxes, the necessitation rule, as well as the distribution axiom, fail. Nevertheless, the fulfillment/nonfulfillment of norms is computable from the truth/falsehood of the propositions which express the required states of affairs. (shrink)

According to a naïve view sometimes apparent in the writings of moral philosophers, ‘ought’ often expresses a relation between agents and actions – the relation that obtains between an agent and an action when that action is what that agent ought to do. It is not part of this naïve view that ‘ought’ always expresses this relation – on the contrary, adherents of the naïve view are happy to allow that ‘ought’ also has an epistemic sense, on which it means, (...) roughly, that some proposition is likely to be the case, and adherents of the naïve view are also typically happy to allow that ‘ought’ also has an evaluative sense, on which it means, roughly, that were things ideal, some proposition would be the case.1 What is important to the naïve view is not that these other senses of ‘ought’ do not exist, but rather that they are not exhaustive – for what they leave out, is the important deliberative sense of ‘ought’, which is the central subject of moral inquiry about what we ought to do and why – and it is this deliberative sense of ‘ought’ which the naïve view understands to express a relation between agents and actions.2 In contrast, logically and linguistically sophisticated philosophers – with a few notable exceptions3 – have rejected this naïve view. According to a dominant perspective in the interpretation of deontic logic and in linguistic semantics, for example, articulated by Roderick Chisholm (1964) and Bernard Williams (1981) in philosophy and in the dominant paradigm in linguistic semantics as articulated in particular by.. (shrink)

From a logical point of view, permissibility can be reduced to possibility by introducing demands which can be met. The alleged reduction is circular from a philosophical perspective, however, because demands are fundamentally deontic. This paper solves this problem by replacing demands which can be met with rules which can be satisfied and violated.

The Moral Law is fulfilled iff everything that ought to be the case is the case, and The Good is realised in a possible world w at a time t iff w is deontically accessible from w at t. In this paper, I will introduce a set of temporal modal deontic systems with propositional quantifiers that can be used to prove some interesting theorems about The Moral Law and The Good. First, I will describe a set of systems without any (...) propositional quantifiers. Then, I will show how these systems can be extended by a couple of propositional quantifiers. I will use a kind of TxW semantics to describe the systems semantically and semantic tableaux to describe them syntactically. Every system will include a constant · that stands for The Good. ‘·’ is read as ‘The Good is realised’. All systems that contain the propositional quantifiers will also include a constant '*' that stands for The Moral Law. '*' is read as ‘The Moral Law is fulfilled’. I will prove that all systems (without the propositional quantifiers) are sound and complete with respect to their semantics and that all systems (including the extended systems) are sound with respect to their semantics. It is left as an open question whether or not the extended systems are complete. (shrink)

A fitting-attitude analysis which understands value in terms of reasons and pro- and con-attitudes allows limited wriggle room if it is to respect a radical division between good and good-for. Essentially, its proponents can either introduce two different normative notions, one relating to good and the other to good-for, or distinguish two kinds of attitude, one corresponding to the analysis of good and the other to good-for. It is argued that whereas the first option faces a counterintuitive scope issue, an (...) attitudinal approach couched in terms of ‘for someone's sake’ attitudes has the unwelcome consequence that whatever is good for someone is also necessarily good. It is argued that this consequence can be avoided if we modify the standard way of formulating the fitting-attitude analysis of final impersonal value. (shrink)

This short paper provides a tentative formalization of Czeżowski's ideas about axiological concepts: Good and Evil are conceived of as modalities rather than as predicates. A natural account of the resulting “ethical logic” appears to be very close to standard deontic logic. If one does not resolve to become an antirealist regarding moral values, a possible way out is to become a revisionist about deontology: convert to intuitionism or some other kind of revisionism in deontic logic, and remain classical in (...) ethical logic. (shrink)

This short note provides a tentative formalization of Czeżowski's ideas about axiological concepts: Good and Evil are conceived of as modalities rather than as predicates. A natural account of the resulting “ethical logic” appears to be very close to standard deontic logic. If one does not resolve to become an antirealist regarding moral values, a possible way out is to become a revisionist about deontology: convert to intuitionism or other kind of revisionism for deontic logic, and remain classical for ethical (...) logic. (shrink)

Tagmemic theory as a semiotic theory can be used to analyze multiple systems of logic and to assess their strengths and weaknesses. This analysis constitutes an application of semiotics and also a contribution to understanding of the nature of logic within the context of human meaning. Each system of logic is best adapted to represent one portion of human rationality. Acknowledging this correlation between systems and their targets helps explain the usefulness of more than one system. Among these systems, the (...) two-valued system of classical logic takes its place. All the systems of logic can be incorporated into a complex mathematical model that has a place for each system and that represents a larger whole in human reasoning. The model can represent why tight formal systems of logic can be applied in some contexts with great success, but in other contexts are not directly applicable. The result suggests that human reasoning is innately richer than any one formal system of logic. (shrink)

There are plenty of classic paradoxes about conditional obligations, like the duty to be gentle if one is to murder, and about “supererogatory” deeds beyond the call of duty. But little has been said about the intersection of these topics. We develop the first general account of conditional supererogation, with the power to solve familiar puzzles as well as several that we introduce. Our account, moreover, flows from two familiar ideas: that conditionals restrict quantification and that supererogation emerges from a (...) clash between justifying and requiring reasons. (shrink)

Possible worlds semantics faces a range of difficulties for at least certain types of modals, especially deontic modals with their distinction between heavy and light permissions and obligations. This paper outlines a new semantics of modals that aims to overcome some of those difficulties. The semantics is based on an a novel ontology of modal objects, entities like obligations, permissions, needs, as well as epistemic states, abilities, and essences. Moreover, it is based on truthmaking, in the sense of Fine’s recent (...) truthmaker semantics. (shrink)

At the heart of the Bayesianism is a rule, Conditionalization, which tells us how to update our beliefs. Typical formulations of this rule are underspecified. This paper considers how, exactly, this rule should be formulated. It focuses on three issues: when a subject’s evidence is received, whether the rule prescribes sequential or interval updates, and whether the rule is narrow or wide scope. After examining these issues, it argues that there are two distinct and equally viable versions of Conditionalization to (...) choose from. And which version we choose has interesting ramifications, bearing on issues such as whether Conditionalization can handle continuous evidence, and whether Jeffrey Conditionalization is really a generalization of Conditionalization. (shrink)

Deference principles are principles that describe when, and to what extent, it’s rational to defer to others. Recently, some authors have used such principles to argue for Evidential Uniqueness, the claim that for every batch of evidence, there’s a unique doxastic state that it’s permissible for subjects with that total evidence to have. This paper has two aims. The first aim is to assess these deference-based arguments for Evidential Uniqueness. I’ll show that these arguments only work given a particular kind (...) of deference principle, and I’ll argue that there are reasons to reject these kinds of principles. The second aim of this paper is to spell out what a plausible generalized deference principle looks like. I’ll start by offering a principled rationale for taking deference to constrain rational belief. Then I’ll flesh out the kind of deference principle suggested by this rationale. Finally, I’ll show that this principle is both more plausible and more general than the principles used in the deference-based arguments for Evidential Uniqueness. (shrink)

Formalising deontic concepts, such as obligation, prohibition and permission, is normally carried out in a modal logic with a possible world semantics, in which some worlds are better than others. The main focus in these logics is on inferring logical consequences, for example inferring that the obligation O q is a logical consequence of the obligations O p and O. In this paper we propose a non-modal approach in which obligations are preferred ways of satisfying goals expressed in first-order logic. (...) To say that p is obligatory, but may be violated, resulting in a less than ideal situation s, means that the task is to satisfy the goal p ∨ s, and that models in which p is true are preferred to models in which s is true. Whereas, in modal logic, the preference relation between possible worlds is part of the semantics of the logic, in this non-modal approach, the preference relation between first-order models is external to the logic. Although our main focus is on satisfying goals, we also formulate a notion of logical consequence, which is comparable to the notion of logical consequence in modal deontic logic. In this formalisation, an obligation O p is a logical consequence of goals G, when p is true in all best models of G. We show how this non-modal approach to the treatment of deontic concepts deals with problems of contrary-to-duty obligations and normative conflicts, and argue that the approach is useful for many other applications, including abductive explanations, defeasible reasoning, combinatorial optimisation, and reactive systems of the production system variety. (shrink)

According to van Fraassen, inference to the best explanation (IBE) is incompatible with Bayesianism. To argue to the contrary, many philosophers have suggested hybrid models of scientific reasoning with both explanationist and probabilistic elements. This paper offers another such model with two novel features. First, its Bayesian component is imprecise. Second, the domain of credence functions can be extended.

Actualists hold that contrary-to-duty scenarios give rise to deontic dilemmas and provide counterexamples to the transmission principle, according to which we ought to take the necessary means to actions we ought to perform. In an earlier article, I have argued, contrary to actualism, that the notion of ‘ought’ that figures in conclusions of practical deliberation does not allow for deontic dilemmas and validates the transmission principle. Here I defend these claims, together with my possibilist account of contrary-to-duty scenarios, against Stephen (...) White’s recent criticism. (shrink)

There is a strong case to be made for thinking that an obscure logic, KR, is better than classical logic and better than any relevant logic. The argument for KR over relevant logics is that KR counts disjunctive syllogism valid, and this is the biggest complaint about relevant logics. The argument for KR over classical logic depends on the normativity of logic and the paradoxes of implication. The paradoxes of implication are taken by relevant logicians to justify relevant logic, but (...) considerations on the normativity of logic show that only some of the paradoxes of implication are genuine. KR avoids all the genuine paradoxes of implication, unlike classical logic. Overall, KR avoids the genuine paradoxes of implication and avoids the major objection to relevant logics. This combination of features provides strong reason to give KR a place in the conversation about the right logic. (shrink)

Standard deontic logic (SDL) is defined on the basis of possible world semantics and is a logic of alethic-deontic modalities rather than deontic modalities alone. The interpretation of the concepts of obligation and permission comes down exclusively to the logical value that a sentence adopts for the accessible deontic alternatives. Here, we set forth a different approach, this being a logic which additionally takes into consideration whether sentences stand in relation to the normative system or to the system of values (...) under which we predicate the deontic qualifications. By taking this aspect into account, we arrive at a logical system which preserves laws proper to a deontic logic but where the standard paradoxes of deontic logic do not arise. It is a logic of strictly-deontic modalities DR. (shrink)

We address the way verb-based and rule-content knowledge are combined in understanding institutional deontics. Study 1 showed that the institutional regulations used in our studies were readily categorised into one of two content groups: rights or duties. Participants perceived rights as benefiting the addressees identified by the rule, whereas they perceived duties as benefiting the collective that imposed the rule. Studies 2, 3, and 4 showed that rule content had clear effects on perceptions of violations and relevance of cases for (...) explaining the rule, even when controlling for deontic verb, phrasing of the action permitted by a right, or the formality of the deontic verb. These effects are incompatible with a simple pragmatic disambiguation approach to pragmatic modulation, as they often induce permissibility judgments that contradict the core semantic meanings of the deontic verbs. Other ways of reconciling verb meaning with rule content should be considered in a fuller the.. (shrink)

Moral obligation and permissibility are usually thought to be interdefinable. Following the pattern of the duality definitions of necessity and possibility, we have that something’s being permissible could be defined as its not being obligatory to not do it. And that something’s being obligatory could be defined as its not being permissible to not do it. In this paper, I argue that neither direction of this alleged interdefinability works. Roughly, the problem is that a claim that some act is obligatory (...) or permissible entails that there is a moral law, whereas a negative claim that some act is not obligatory or not permissible does not. Nevertheless, one direction of the interdefinability can potentially be salvaged. I argue that, if we do not require the conceptual possibility of moral dilemmas, then there is a way to plausibly define obligation in terms of permissibility. I conclude that permissibility is the only feasible deontic primitive. (shrink)

In the present paper we model the Navya-Nyāya analysis of Vedic and secular injunctions and prohibitions by means of Giordani’s and Canavotto’s system ADL of dynamic deontic logic. Navya-Naiyāyikas analyze the meaning of injunctions and prohibitions by reducing them to plain indicative statements about certain properties whose presence or absence in the enjoined or prohibited action serves as a criterion for the truth or falsity of the “inducing” or “restraining knowledge”, a kind of qualificative cognition instilled in the recipient of (...) an injunction or prohibition. Thus, Navya-Naiyāyikas have found their own way to solve Jørgensen’s Puzzle concerning the very idea of a deontic logic as a tool to analyze arguments based on sentences which do not seem to be truth-apt. The teleological aspect of the Navya-Nyāya characterization of an enjoined or prohibited action can also give a clue to solutions of other puzzles and paradoxes which have beset the development of deontic logic in the West. A specific contrary-to-duty puzzle from the Indian tradition is related to the śyena, a malefic sacrifice meant for harming one’s enemy. The Vedic injunction to perform such a sacrifice runs counter to a religious practitioner’s duty not to harm a living being. In the present paper we examine the cogency of the very different solutions to this dilemma suggested by the Mīmāṃsaka Prabhākara on the one hand and the Navya-Naiyāyika Gaṅgeśa on the other hand. (shrink)

Popper emphasised both the problem-solving nature of human knowledge, and the need to criticise a scientific theory as strongly as possible. These aims seem to contradict each other, in that the former stresses the problems that motivate scientific theories while the one ignores the character of the problems that led to the formation of the theories against which the criticism is directed. A resolution is proposed in which problems as such are taken as prime in the search for knowledge, and (...) subject to discussion. This approach is then applied to the problem of induction. Popper set great stake to his solution of it, but others doubted its legitimacy, in ways that are clarified by changing the form of the induction problem itself. That change draws upon logic, which is the subject of another application: namely, in contrast to Popper’s adhesion to classical logic as the only welcome form (because of the maximal strength of criticism that it dispenses), can other logics be used without abandoning his philosophy of criticism? (shrink)

We present a new axiomatization of the deontic fragment of Anderson's relevant deontic logic, give an Andersonian reduction of a relevant version of Mally's deontic logic previously discussed in this journal, study the effect of adding propositional quantification to Anderson's system, and discuss the meaning of Anderson's propositional constant in a wide range of Andersonian deontic systems.

This paper concerns the relationship between transitivity of entailment, omega-inconsistency and nonstandard models of arithmetic. First, it provides a cut-free sequent calculus for non-transitive logic of truth STT based on Robinson Arithmetic and shows that this logic is omega-inconsistent. It then identifies the conditions in McGee for an omega-inconsistent logic as quantified standard deontic logic, presents a cut-free labelled sequent calculus for quantified standard deontic logic based on Robinson Arithmetic where the deontic modality is treated as a predicate, proves omega-inconsistency (...) and shows thus, pace Cobreros et al., that the result in McGee does not rely on transitivity. Finally, it also explains why the omega-inconsistent logics of truth in question do not require nonstandard models of arithmetic. (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)

In this paper I argue that deontic modals are hyperintensional, i.e. logically equivalent contents cannot be substituted in their scope. I give two arguments, one deductive and the other abductive. First, I show that the contrary thesis leads to falsity; second, I argue that a hyperintensional theory of deontic modals fares better than its rivals in terms of elegance, theoretical simplicity and explanatory power. I then propose a philosophical analysis of this thesis and outline some consequences. In Section 1 I (...) introduce and define deontic modality and hyperintensionality. In Section 2 I give a reductio for the hyperintensionality of deontic modals. If the argument is sound, a useful corollary is that deontic modals are also non-intensional, and therefore possible-world semantics accounts are illfitted for them. I then show how the main result can be strengthened or weakened by varying the definition of logical validity. In Section 3 I give an abductive argument for the hyperintensionality of deontic modals, arguing that with a single move we are able to solve many paradoxes and puzzles traditionally troubling deontic logic. I present a version of a hyperintensional deontic logic in an appendix, which I prove is sound and complete with respect to a version of truthmaker semantics. (shrink)

We defend three controversial claims about preference, credence, and choice. First, all agents (not just rational ones) have complete preferences. Second, all agents (again, not just rational ones) have real-valued credences in every proposition in which they are confident to any degree. Third, there is almost always some unique thing we ought to do, want, or believe.

Criticism is a staple of the scientific enterprise and of the social epistemology of science. Philosophical discussions of criticism have traditionally focused on its roles in relation to objectivity, confirmation, and theory choice. However, attention to criticism and to criticizability should also inform our thinking about scientific pursuits: the allocation of resources with the aim of developing scientific tools and ideas. In this paper, we offer an account of scientific pursuitworthiness which takes criticizability as its starting point. We call this (...) the apokritic model of pursuit. Its core ideas are that pursuits are practices governed by norms for asking and answering questions, and that criticism arises from the breach of these norms. We illustrate and advertise our approach using examples from institutional grant review, neuroscience, and sociology. We show that the apokritic model can unify several indices of criticizability, that it can account for the importance of criticizing pursuits in scientific practice, and that it can offer ameliorative advice to erstwhile pursuers. (shrink)

Logical geometry systematically studies Aristotelian diagrams, such as the classical square of oppositions and its extensions. These investigations rely heavily on the use of bitstrings, which are compact combinatorial representations of formulas that allow us to quickly determine their Aristotelian relations. However, because of their general nature, bitstrings can be applied to a wide variety of topics in philosophical logic beyond those of logical geometry. Hence, the main aim of this paper is to present a systematic technique for assigning bitstrings (...) to arbitrary finite fragments of formulas in arbitrary logical systems, and to study the logical and combinatorial properties of this technique. It is based on the partition of logical space that is induced by a given fragment, and sheds new light on a number of interesting issues, such as the logic-dependence of the Aristotelian relations and the subtle interplay between the Aristotelian and Boolean structure of logical fragments. Finally, the bitstring technique also allows us to systematically analyze fragments from contemporary logical systems, such as public announcement logic, which could not be done before. (shrink)

We define a family of intuitionistic non-normal modal logics; they can be seen as intuitionistic counterparts of classical ones. We first consider monomodal logics, which contain only Necessity or Possibility. We then consider the more important case of bimodal logics, which contain both modal operators. In this case we define several interactions between Necessity and Possibility of increasing strength, although weaker than duality. We thereby obtain a lattice of 24 distinct bimodal logics. For all logics we provide both a Hilbert (...) axiomatisation and a cut-free sequent calculus, on its basis we also prove their decidability. We then define a semantic characterisation of our logics in terms of neighbourhood models containing two distinct neighbourhood functions corresponding to the two modalities. Our semantic framework captures modularly not only our systems but also already known intuitionistic non-normal modal logics such as Constructive K and the propositional fragment of Wijesekera’s Constructive Concurrent Dynamic Logic. (shrink)

Trying to overcome Dugundji’s result on uncharacterisability of modal logics by finite logical matrices, Kearns and Ivlev proposed, independently, a characterisation of some modal systems by means of four-valued multivalued truth-functions , as an alternative to Kripke semantics. This constitutes an antecedent of the non-deterministic matrices introduced by Avron and Lev . In this paper we propose a reconstruction of Kearns’s and Ivlev’s results in a uniform way, obtaining an extension to another modal systems. The first part of the paper (...) is devoted to four-valued Nmatrices, including Kearns’s and Ivlev’s. Besides proving with full details Kearns’s results for T, S4 and S5, we also obtain a characterisation of the system B by four-valued Nmatrices with level valuations. Concerning Ivlev’s results, two new modal systems are introduced and char.. (shrink)

This paper analyzes Mally’s system of deontic logic, introduced in his The Basic Laws of Ought: Elements of the Logic of Willing (1926). We discuss Mally’s text against the background of some contributions in the literature which show that Mally’s axiomatic system for deontic logic is flawed, in so far as it derives, for an arbitrary A, the theorem “A ought to be the case if and only if A is the case”, which represents a collapse of obligation. We then (...) try to sort out and understand which axioms are responsible for the collapse and consider two ways of amending Mally’s system: (i) by changing its original underlying logical basis, that is classical logic, and (ii) by modifying Mally’s axioms. (shrink)

Khemlani et al. (2018) mischaracterize logic in the course of seeking to show that mental model theory (MMT) can accommodate a form of inference (, let us label it) they find in a high percentage of their subjects. We reveal their mischaracterization and, in so doing, lay a landscape for future modeling by cognitive scientists who may wonder whether human reasoning is consistent with, or perhaps even capturable by, reasoning in a logic or family thereof. Along the way, we note (...) that the properties touted by Khemlani et al. as innovative aspects of MMT‐based modeling (e.g., nonmonotonicity) have for decades been, in logic, acknowledged and rigorously specified by families of (implemented) logics. Khemlani et al. (2018) further declare that is “invalid in any modal logic.” We demonstrate this to be false by our introduction (Appendix A) of a new propositional modal logic (within a family of such logics) in which is provably valid, and by the implementation of this logic. A second appendix, B, partially answers the two‐part question, “What is a formal logic, and what is it for one to capture empirical phenomena?”. (shrink)

Does Duncan Kennedy successfully cannibalize jurisprudence? He attempts to do it by demonstrating the inexistence of rightness in legal argumentation. If there is no right legal argument, then there is no right answer in adjudication, adjudication is not a rational enterprise and legal doctrine cannot be said to be a science. It can be shown that skepticism is self-defeating. Duncan Kennedy can avoid self defeat only because he actually believes in a lot of legal arguments. His thesis that judges decide (...) questions of policy without any methodology that distinguishes them from legislators does not hold. Judicial reasoning is subject to constraints that do not affect legislators. It must be based on the sources of law and is limited by rules of procedure. Even when the judges have ‘interstitial’ legislative powers they are, unlike the legislator, bound to fit the system and their decisions are considered in procedure from the perspective of the right answer doctrine. The only work that can convincingly refute the skeptic argument against legal science is the reconstruction of jurisprudence as a scientific enterprise. Such work is beyond the scope of any single paper. The article aims to give some inspirations for such a task. (shrink)