During the 13th century, several logicians in the Latin medieval tradition showed a special interest in the nature of impossibility, and in the different kinds or ‘degrees’ of impossibility that could be distinguished. This discussion resulted in an analysis of the modal concept with a fineness of grain unprecedented in earlier modal accounts. Of the several divisions of the term ‘impossible’ that were offered, one became particularly relevant in connection with the debate on ars obligatoria and positio impossibilis: the (...) distinction between ‘intelligible’ and ‘unintelligible’ impossibilities. In this article, I consider some 13th-century tracts on obligations that provide an account of the relation between impossibility and intelligibility and discuss the inferential principles that are permissible when we reason from an impossible – but intelligible – premise. I also explore the way in which the 13th-century reflection on this topic survives, in a revised form, in some early 14th-century accounts of positio, namely, those of William of Ockham, Roger Swineshead and Thomas Bradwardine. (shrink)

A lump theorist claims that ordinary objects are spread out across possible worlds, much like many of us think that tables are spread out across space. We are not wholly located in any one particular world, the lump theorist claims, just as we are not wholly spatially located where one’s hand is. We are modally spread out, a trans-world mereological sum of world-bound parts. We are lump sums of modal parts. And so are all other ordinary objects. In this paper, (...) I explore lump theory and investigate five arguments against it. These arguments may be the primary reasons why lump theory has not been widely accepted––or extensively explored––until now. I maintain that these arguments can be answered, and moreover, that accepting lump theory has distinct advantages, making it a competitive view in its own right. (shrink)

In our everyday discourse, most of us use modal statements to express possibility, necessity, or contingency. Logicians, linguists, and philosophers of language tend to use the possible world discourse to analyse the semantics of this kind of sentences. There is a disadvantage of this method: in the usual Quinean meta-ontology it commits the users to the existence of possible worlds. Even though there are many theories on metaphysics of these possible worlds, I will focus on the fictionalist approach, which (...) aims to suspend the undesired ontological commitment. Therefore it is an anti-realist theory. The fictionalist strategy is based on the idea that according to our common-sense ontology, fictions and fictional entities do not exist, and one can treat the possible world discourse as a fiction, and the possible worlds as fictional entities. However, in the last two decades, realist theories about fictions and fictional entities have arisen, especially the abstract artefact theory. In this paper I try to revise the fictionalist approach to modality by keeping the main idea that possible worlds are fictional entities, while accepting that fictional entities are abstract artefacts. The result is a new realist theory of modal fictionalism. (shrink)

Medieval authors generally agreed that we have the freedom to choose among alternative possibilities. But most medieval authors also thought that there are situations in which one cannot do otherwise, not even will otherwise. They also thought when willing necessarily, the will remains free. The questions, then, are what grounds the necessity or contingency of the will’s acts, and – since freedom is not defined by the ability to choose – what belongs to the essential character of freedom, (...) the ratio libertatis. This article studies medieval theories of freedom without choice from William of Auxerre to William of Ockham and their background in Augustine, Anselm of Canterbury, and Bernard of Clairvaux. (shrink)

Marchetto of Padua, Lucidarium, authentic, plagal, perfect, imperfect, pluperfect, mixed, odd numbers, even numbers, Aristotle, Metaphysics, Alcmaeon of Croton, causa significationis, dyapente, diatesseron, concord, senaria, Pomerium, Donatus, Vetulus, mode 5, commixed, corda, discant, dyad, voice leading.

Provisional draft, pre-production copy of my book “The Modal Future” (forthcoming with Cambridge University Press).

The function of a trait token is usually defined in terms of some properties of other (past, present, future) tokens of the same trait type. I argue that this strategy is problematic, as trait types are (at least partly) individuated by their functional properties, which would lead to circularity. In order to avoid this problem, I suggest a way to define the function of a trait token in terms of the properties of the very same trait token. To able to (...) allow for the possibility of malfunctioning, some of these properties need to be modal ones: a function of a trait is to do F just in case its doing F would contribute to the inclusive fitness of the organism whose trait it is. Function attributions have modal force. Finally, I explore whether and how this theory of biological function could be modified to cover artifact function. (shrink)

In a series of papers, Bence Nanay has recently put forward and defended a new theory of function, which he calls the ‘Modal Theory of Function’. In this article, I critically address this theory and argue that it fails to fulfill some key desiderata that a satisfactory theory of function must comply with. As a result, I conclude that, whatever property Nanay’s notion of function refers to, it is not the property having the function that is standardly attributed in science.

Discrimination is a central epistemic capacity but typically, theories of discrimination only use discrimination as a vehicle for analyzing knowledge. This paper aims at developing a self-contained theory of discrimination. Internalist theories of discrimination fail since there is no compelling correlation between discriminatory capacities and experiences. Moreover, statistical reliabilist theories are also flawed. Only a modal theory of discrimination is promising. Versions of sensitivity and adherence that take particular alternatives into account provide necessary and sufficient conditions on (...) discrimination. Safety in contrast is not sufficient for discrimination as there are cases of safety that are clearly instances of discrimination failure. The developed account of discrimination between objects will be extended to discrimination between kinds and between types. (shrink)

ABSTRACTRecent debate over the semantics and pragmatics of epistemic modals has focused on intuitions about cross-contextual truth-value assessments. In this paper, we advocate a different approach to evaluating theories of epistemic modals. Our strategy focuses on judgments of the incompatibility of two different epistemic possibility claims, or two different truth value assessments of a single epistemic possibility claim. We subject the predictions of existing theories to empirical scrutiny, and argue that existing contextualist and relativist theories are unable (...) to account for the full pattern of observed judgments. As a way of illustrating the theoretical upshot of these results, we conclude by developing a novel theory of epistemic modals that is able to predict the results. (shrink)

The traditional conception of risk is probabilistic, according to which the degree of risk of an event is determined by the probability of its occurence. Recently this view was challenged by Duncan Pritchard (2015, 2016), who suggested a modal theory of risk, centered in the idea that the riskiness of events depends on the modal distance between the actual world and worlds where the event obtains. What is attractive about this theory, according to Pritchard, is that it explains our judgement (...) about cases in which two equally probable events seem to have different degrees of risk. The modal theory of risk, however, has its own shortcomings: according to Bricker (2018), there are cases in which risk judgements are not tracking modal distance; there is also the problem of determining the risk of events that occur in the actual world, since the theory seems to imply that they are maximally risky because the actual world is maximally similar to itself (EBERT; SMITH; DURBACH, 2020). The modal conception of risk is also at odds with the most natural forms of reasoning over the morality of risk imposition. I begin exploring the two conceptions of risk, emphasizing their strenghts and weaknesses. I then argue that the probabilistic conception can be defended from objections, and a pluralistic theory of risk, although less unified, deserves to be considered. -/- . (shrink)

The topic of a priori knowledge is approached through the theory of evidence. A shortcoming in traditional formulations of moderate rationalism and moderate empiricism is that they fail to explain why rational intuition and phenomenal experience count as basic sources of evidence. This explanatory gap is filled by modal reliabilism -- the theory that there is a qualified modal tie between basic sources of evidence and the truth. This tie to the truth is then explained by the theory of concept (...) possession: this tie is a consequence of what, by definition, it is to possess (i.e., to understand) one’s concepts. A corollary of the overall account is that the a priori disciplines (logic, mathematics, philosophy) can be largely autonomous from the empirical sciences. (shrink)

I provide an examination and comparison of modal theories for underwriting different non-modal theories of sets. I argue that there is a respect in which the `standard' modal theory for set construction---on which sets are formed via the successive individuation of powersets---raises a significant challenge for some recently proposed `countabilist' modal theories (i.e. ones that imply that every set is countable). I examine how the countabilist can respond to this issue via the use of regularity axioms and (...) raise some questions about this approach. I argue that by comparing them with the `standard' uncountabilist theory, a new approach that brings in arbitrariness rather than the strict controls of forcing is desirable. (shrink)

We develop a theory of necessity operators within a version of higher-order logic that is neutral about how fine-grained reality is. The theory is axiomatized in terms of the primitive of *being a necessity*, and we show how the central notions in the philosophy of modality can be recovered from it. Various questions are formulated and settled within the framework, including questions about the ordering of necessities under strength, the existence of broadest necessities satisfying various logical conditions, and questions about (...) their logical behaviour. We also wield the framework to probe the conditions under which a logicist account of necessities is possible, in which the theory is completely reducible to logic. (shrink)

The study of reference often leads to addressing fundamental issues in semantics, metaphysics and epistemology; this suggests that reference is closely linked to the three realms. The overall purpose of this study is to elucidate the structure of some of these links, through a close examination of the “mechanism” of reference. As in many other enquiries, considering the possible (i.e., the modal,) in addition to the actual proves very helpful in clarifying and explicating insights. The reference of a term with (...) respect to possible worlds is commonly called “intension”; so this is a study of intensions. The main contribution of the study is an outline for a “calculator” of intensions. It is argued that the intension of a term is a function of three variables: (a) the way in which the term “picks out” its referent in different possible worlds (semantics); (b) criteria of identity (metaphysics); and (c) the actual state of affairs (actuality). While considering different possible values for these variables, it is demonstrated how the variables combine to generate the term’s intension. In other words, the result is a calculator that when provided with the required values, yields the reference of the term in different possible worlds. By taking into account the possible gap between what we take the values of these variables to be and what they may in fact be, we also gain important insights into the epistemic aspect of reference. In addition, since a rigid designator is a term with constant intension, the proposed thesis provides an elaborate account of rigidity. The first chapter is devoted to the development of the calculator of intensions. Each of the following three chapters elaborates on one aspect of intensions, namely, the semantic, metaphysical and epistemic aspects. In the course of these chapters, various familiar puzzles pertaining to the respective philosophical realms are addressed (many of these puzzles are discussed in Kripke’s Naming and Necessity – a work that considerably inspired this study). In the fifth and last chapter the analysis of intensions is applied to two case-studies from relatively recent philosophical literature: the Kripke-Lewis debate over the identity theory of mind, and the debate over the significance of Donnellan’s referential/attributive distinction. The novel accounts that these applications generate purport to illustrate the importance and originality of the proposed thesis. (shrink)

Relative to any reasonable frame, satisfiability of modal quantificational formulae in which “= ” is the sole predicate is undecidable; but if we restrict attention to satisfiability in structures with the expanding domain property, satisfiability relative to the familiar frames (K, K4, T, S4, B, S5) is decidable. Furthermore, relative to any reasonable frame, satisfiability for modal quantificational formulae with a single monadic predicate is undecidable ; this improves the result of Kripke concerning formulae with two monadic predicates.

Some philosophers of fiction – most famously Jerold Levinson1 - have tried to argue that fictional narrators can never be identified with real authors. This argument relies on the claim that narration involves genuine assertion (not just the pretense of assertion that lacks truthfulness) and that real authors are not in a position to assert anything about beings on the fictional plain - given that they don’t rationally believe in their existence. This debate on the status of narrators depends on (...) the idea that fictional beings and beings in the real worlds reside, as it were, at different levels. The assumption that there is a gap separating the levels of fiction and reality serves as a rationale for the claim that real authors could not possibly be en rapport with the fictional characters that they create (e.g. entertain beliefs about them, etc.). (shrink)

This article seeks the origin, in the theories of Ibn al-Haytham (Alhazen), Descartes, and Berkeley, of two-stage theories of spatial perception, which hold that visual perception involves both an immediate representation of the proximal stimulus in a two-dimensional ‘‘sensory core’’ and also a subsequent perception of the three dimensional world. The works of Ibn al-Haytham, Descartes, and Berkeley already frame the major theoretical options that guided visual theory into the twentieth century. The field of visual perception was the (...) first area of what we now call psychology to apply mathematics, through geometrical models as used by Euclid, Ptolemy, Ibn al-Haytham, and Descartes (among others). The article shows that Kepler’s discovery of the retinal image, which revolutionized visual anatomy and entailed fundamental changes in visual physiology, did not alter the basic structure of theories of spatial vision. These changes in visual physiology are advanced especially in Descartes' Dioptrics and his L'Homme. Berkeley develops a radically empirist theory vision, according to which visual perception of depth is learned through associative processes that rely on the sense of touch. But Descartes and Berkeley share the assertion that there is a two-dimensional sensory core that is in principle available to consciousness. They also share the observation that we don't usually perceived this core, but find depth and distance to be phenomenally immediate, a point they struggle to accommodate theoretically. If our interpretation is correct, it was not a change in the theory of the psychology of vision that engendered the idea of a sensory core, but rather the introduction of the theory into a new metaphysical context. (shrink)

Modal intuitions are the primary source of modal knowledge but also of modal error. According to the theory of modal error in this paper, modal intuitions retain their evidential force in spite of their fallibility, and erroneous modal intuitions are in principle identifiable and eliminable by subjecting our intuitions to a priori dialectic. After an inventory of standard sources of modal error, two further sources are examined in detail. The first source - namely, the failure to distinguish between metaphysical possibility (...) and various kinds of epistemic possibility - turns out to be comparatively easy to untangle and poses little threat to intuition-driven philosophical investigation. The second source is the local misunderstanding of one's concepts . This pathology may be understood on analogy with a patient who is given a clean bill of health at his annual check-up, despite his having a cold at the time of the check-up: although the patient's health is locally disrupted, his overall health is sufficiently good to enable him to overcome the cold without external intervention. Even when our understanding of certain pivotal concepts has lapsed locally, our larger body of intuitions is sufficiently reliable to allow us, without intervention, to ferret out the modal errors resulting from this lapse of understanding by means of dialectic and/or a process of a priori reflection. This source of modal error, and our capacity to overcome it, has wide-ranging implications for philosophical method - including, in particular, its promise for disarming skepticism about the classical method of intuition-driven investigation itself. Indeed, it is shown that skeptical accounts of modal error are ultimately self-defeating. (shrink)

This paper investigates the prospects for a semantic theory that treats disjunction as a modal operator. Potential motivation for such a theory comes from the way in which modals embed within disjunctions. After reviewing some of the relevant data, I go on to distinguish a variety of modal theories of disjunction. I analyze these theories by considering pairs of conflicting desiderata, highlighting some of the tradeoffs they must face.

Philosophers and psychologists widely hold that artifact categories – just like biological categories – are individuated by their function. But recent empirical findings in psychology question this assumption. My proposal is to suggest a way of squaring these findings with the central role function should play in individuating artifact categories. But in order to do so, we need to give up on the standard account of artifact function, according to which function is fixed by design, and replace it with a (...) more context-sensitive account, according to which function attributions depend on the explanatory context and, as a result, categorization also depends on the explanatory context, just as the empirical findings from psychology suggest. I argue that the recent ‘modal theory of function’ originally proposed to explain biological function, is capable of providing such an account of artifact function. (shrink)

Richard Shusterman suggested that Maurice Merleau-Ponty neglected “‘lived somaesthetic reflection,’ that is, concrete but representational and reflective body consciousness.” While unsure about this assessment of Merleau-Ponty, lived somaesthetic reflection, or what the late Sam Mallin called “body phenomenology”—understood as a meditation on the body reflecting on both itself and the world—is my starting point. Another is John Dewey’s bodily theory of perception, augmented somewhat by Merleau-Ponty. -/- With these starting points, I spent roughly 20 hours with St. Benedict Restores Life (...) to a Young Monk (c. 1360), a work of tempera and gold leaf on panel, by Giovanni Del Biondo, active in Italy from 1356 to 1398, on display in the Art Gallery of Ontario’s permanent collection. Following Dewey’s suggestion that “[t]he eye ... is only the channel through which a total response takes place,” meaning that motor, emotional, intellectual and non-visual perceptual capacities become active when we encounter paintings, I describe how the work engaged a range of bodily modalities; and how reflecting on these, in turn, supplied phenomenal articulations of life negating, preserving and enhancing forces important in the culture that produced it, and famously discussed by Friedrich Nietzsche. By virtue of the approach adopted, I also demonstrate Dewey’s belief that intimate engagement with art entails a total coordination of one’s capacities around the artwork, while simultaneously reinforcing Merleau-Ponty’s ideas about perception and how we can find phenomenal articulations of concepts such as the Nietzschean ones just mentioned. While focusing on Del Biondo’s painting, my main purpose is to engage in body phenomenology practices, and to show, in the words of Shusterman, how “[w]e might sharpen our appreciation of art through more attention to our somaesthetic feelings involved in perceiving art” and indeed the world. (shrink)

Bundle theories identify material objects with bundles of properties. On the traditional approach, these are the properties possessed by that material object. That view faces a deep problem: it seems to say that all of an object’s properties are essential to it. Essential bundle theory attempts to overcome this objection, by taking the bundle as a specification of the object’s essential properties only. In this paper, I show that essential bundle theory faces a variant of the objection. To avoid (...) the problem, the theory must accept the contingency of identity. I show how this can be achieved in a coherent and well-motivated way, a way that isn’t available to traditional bundle theories. (shrink)

Many philosophers believe that there is a causal condition on perception, and that this condition is a conceptual truth about perception. A highly influential argument for this claim is based on intuitive responses to Gricean-style thought experiments. Do the folk share the intuitions of philosophers? Roberts et al. (2016) presented participants with two kinds of cases: Blocker cases (similar to Grice’s case involving a mirror and a pillar) and Non-Blocker cases (similar to Grice’s case involving a clock and brain stimulation). (...) They found that a substantial minority agreed that seeing occurs in the Non-Blocker cases, and that in the Blocker cases significantly less agreed that seeing occurs. They thus hypothesized that folk intuitions better align with a no blocker condition than with a causal condition. This paper continues this line of enquiry with two new experiments. The paper investigates the generality and robustness of Roberts et al.’s findings by expanding the sense modalities tested from only vision to audition and olfaction as well. The paper also uses Gricean-style thought experiments as a case study for investigating the “reflection defense” against the negative project in experimental philosophy. Our results replicate and extend Roberts et al.’s study and support their hypothesis that folk intuitions better align with a no blocker condition. They also provide an empirical reason to doubt the reflection defense. (shrink)

There are three theories in the epistemology of modality that have received sustained attention over the past 20 years: conceivability-theory, counterfactual-theory, and deduction-theory. In this paper we argue that all three face what we call the problem of modal epistemic friction. One consequence of the problem is that for any of the three accounts to yield modal knowledge, the account must provide an epistemology of essence. We discuss an attempt to fend off the problem within the context of the (...) internalism versus externalism debate about epistemic justification. We then investigate the effects that the PMEF has on reductive and non-reductive theories of the relation between essence and modality. (shrink)

At least since Aristotle's famous discussion of the sea-battle tomorrow in On Interpretation 9, philosophers have been fascinated by a rich set of interconnecte.

This is the only complete logic for properties, relations, and propositions (PRPS) that has been formulated to date. First, an intensional abstraction operation is adjoined to first-order quantifier logic, Then, a new algebraic semantic method is developed. The heuristic used is not that of possible worlds but rather that of PRPS taken at face value. Unlike the possible worlds approach to intensional logic, this approach yields a logic for intentional (psychological) matters, as well as modal matters. At the close of (...) the paper, the origin of incompleteness in logic is investigated. The culprit is found to be the predication relation, a relation on properties and relations that is expressed in natural language by the copula. (shrink)

Philosophical debate about the meaning of normative terms has long been pulled in two directions by the apparently competing ideas: (i) ‘ought’s do not describe what is actually the case but rather prescribe possible action, thought, or feeling, (ii) all declarative sentences deserve the same general semantic treatment, e.g. in terms of compositionally specified truth conditions. In this paper, I pursue resolution of this tension by rehearsing the case for a relatively standard truth-conditionalist semantics for ‘ought’ conceived as a necessity (...) modal and proposing a revision to it motivated by the distinctively prescriptive character of some deontic modals. In my view, this puts pressure on a popular conception of one of the core debates of metanormative theory between realists and antirealists. To make good on this claim, I go on to explore two very general ways we might interpret the results of compositional semantics—“representationalism” and “inferentialism”—in order to argue that, contrary to what is generally assumed, both can capture the special prescriptivity of ‘ought’ and both can countenance compositionally specified and informative truth-conditions for ought-sentences. Hence, my main thesis is that the deciding factor between them should not be which of ideas (i) and (ii) we are more impressed by but rather what we think of the relative merits of how representationalism and inferentialism respect these ideas. I’m inclined to favor an antirealist form of inferentialism, but the task I’ve set myself here is mainly to articulate the view in the context of metanormative theory and the semantics of deontic modals rather than try to defend it fully. To this purpose, towards the end I also briefly compare and contrast inferentialism with a third “ideationalist” metasemantic view, which may be an attractive home for some sophisticated versions of metanormative expressivism. Depending on how expressivism is worked out, it may be completely compatible with and so perhaps usefully combined with inferentialism or it may offer a competing way to respect ideas (i) and (ii). (shrink)

In this essay, I consider some logical treatises and commentaries from the first decades of the 12th century (many of which are still unedited) which contain a discussion on modalities and modal logic. After presenting a short catalogue of these sources and a description of their common features, I shall focus on some definitions of the modal term “necessarium” which are provided in them. As we will see, Abelard and logicians of his time advanced three different characterizations of this (...) term: necessity was either defined in terms of unavoidability (ineuitabilitas), or in terms of immutability and omnitemporality (impermutabilitas, sempiternitas), or again in terms of absolute necessity as opposed to conditioned one (necessitas absoluta vs. determinata). I argue that the temporal understanding of necessity in terms of omnitemporality, inherited from ancient sources and extensively used by Abelard and others in the first years of the twelfth-century, started to disappear in texts datable from around the 1120, perhaps due to several difficulties that were related to this definition when applied in logical contexts. I also discuss how the notion of necessitas determinata was used by Abelard’s contemporaries to qualify the modal status of present and past events, which were generally believed to be necessary only in a “weak” and harmless sense that did not prevent them from being contingent. -/- . (shrink)

In this paper, I discuss the main characteristics of the epistemology of modal rationalism by proceeding from the critical investigation of Peacocke’s theory of modality. I build on arguments by Crispin Wright and Sonia Roca-Royes, which are generalised and supplemented by further analysis, in order to show that principle-based accounts have little prospects of succeeding in their task of providing an integrated account of the metaphysics and the epistemology of modality. I argue that it is unlikely that we will able (...) to develop an exhaustive and accurate principle-based account that discriminates objectively between correct and deviant modal knowledge. Even if such an account can be formulated, a non-circular way of justifying its necessity also seems to be out of our reach. (shrink)

The paper considers contemporary models of presumption in terms of their ability to contribute to a working theory of presumption for argumentation. Beginning with the Whatelian model, we consider its contemporary developments and alternatives, as proposed by Sidgwick, Kauffeld, Cronkhite, Rescher, Walton, Freeman, Ullmann-Margalit, and Hansen. Based on these accounts, we present a picture of presumptions characterized by their nature, function, foundation and force. On our account, presumption is a modal status that is attached to a claim and has the (...) effect of shifting, in a dialogue, a burden of proof set at a local level. Presumptions can be analysed and evaluated inferentially as components of rule-based structures. Presumptions are defeasible, and the force of a presumption is a function of its normative foundation. This picture seeks to provide a framework to guide the development of specific theories of presumption. (shrink)

My aim in this paper is to sketch, with a broad brush and in bare outlines, an approach to modal epistemology that is characterized by three distinctive features. First, the approach is agency-based: it locates the roots of our modal thought and knowledge in our experience of our own agency. Second, the approach is ambitious in that it takes the experience of certain modal properties in agency to be the sole distinctive feature of specifically modal thought and knowledge; everything that (...) we know about modality beyond the experience of agency is a matter of applying standard methods of inquiry such as deduction, induction and abductive methods for choosing between theories. Third, the account holds that modal thought and knowledge is, first and foremost, about modal properties that are sufficiently like those encountered in agency. (shrink)

The sample space of the chance distribution at a given time is a class of possible worlds. Thanks to this connection between chance and modality, one’s views about modal space can have significant consequences in the theory of chance and can be evaluated in part by how plausible these implications are. I apply this methodology to evaluate certain forms of modal contingentism, the thesis that some facts about what is possible are contingent. Any modal contingentist view that meets certain conditions (...) that I specify generates difficulties in the philosophy of chance, including a problem usually associated with Humeanism that is known as ‘the problem of undermining futures’. I consider two well-known versions of modal contingentism that face this difficulty. The first version, proposed by Hugh Chandler and Nathan Salmon, rests on an argument for the claim that many individuals have their modal features contingently. The second version is motivated by the thesis that the existence of a possible world depends on the existence of the contingent individuals inhabiting it, and that many worlds are therefore contingent existents. (shrink)

This essay examines the way in which the modal concept of necessity was discussed and analyzed in some eleventh- and early twelfth-century sources, such as Peter Damian’s De divina omnipotentia, Anselm of Canterbury’s Cur deus homo and several anonymous commentaries on Aristotle’s De interpretatione that were presumably composed in the first two decades of the twelfth century by logicians connected to William of Champeaux’s and Peter Abelard’s milieu. My aim is to offer a comparison of these different sources with respect (...) to their use of the Boethian distinction between two types or kinds of necessity, namely, the “absolute” or “simple” necessity that is involved in statements like “God is necessarily immortal” or “it is necessary for humans to be animals”, and the “conditional” or “temporal” necessity that is at stake when we say, for instance, that someone necessarily walks when he is walking. (shrink)

Advocates of Expressivism about basically any kind of language are best-served by abandoning a traditional content-centric approach to semantic theorizing, in favor of an update-centric or dynamic approach (or so this paper argues). The type of dynamic approach developed here — in contrast to the content-centric approach — is argued to yield canonical, if not strictly classical, "explanations" of the core semantic properties of the connectives. (The cases on which I focus most here are negation and disjunction.) I end the (...) paper by describing a distinctive sense in which mental states might play a fundamental role in the practice of semantic theorizing (as I understand it), and I connect this to a distinctive account of the pragmatic function of, e.g., a normatively laden claim in discourse. (shrink)

Higher-order theories of properties, relations, and propositions are known to be essentially incomplete relative to their standard notions of validity. It turns out that the first-order theory of PRPs that results when first-order logic is supplemented with a generalized intensional abstraction operation is complete. The construction involves the development of an intensional algebraic semantic method that does not appeal to possible worlds, but rather takes PRPs as primitive entities. This allows for a satisfactory treatment of both the modalities (...) and the propositional attitudes, and it suggests a general strategy for developing a comprehensive treatment of intensional logic. (shrink)

This paper sketches a new and somewhat heterodox metaphysical theory of consciousness: the “many-worlds theory”. It drops the assumption that all conscious subjects’ experiences are features of one and the same world and instead associates different subjects with different “first-personally centred worlds”. We can think of these as distinct “first-personal realizers” of a shared “third-personal world”, where the latter is supervenient, in a sense to be explained. This is combined with a form of modal realism, according to which different subjects’ (...) first-personally centred worlds are all real, though only one of them is present for each subject. The theory offers a novel way of capturing the irreducibly subjective nature of conscious experience without lapsing into solipsism. The paper also looks at some scientific theories of consciousness, such as integrated information theory, through the proposed lens and reconsiders the hard problem of consciousness. (shrink)

Non‐Humean theories of natural necessity invoke modally‐laden primitives to explain why nature exhibits lawlike regularities. However, they vary in the primitives they posit and in their subsequent accounts of laws of nature and related phenomena (including natural properties, natural kinds, causation, counterfactuals, and the like). This article provides a taxonomy of non‐Humean theories, discusses influential arguments for and against them, and describes some ways in which differences in goals and methods can motivate different versions of non‐Humeanism (and, for (...) that matter, Humeanism). In short, this article provides an introduction to non‐Humeanism concerning the metaphysics of laws of nature and natural necessity. (shrink)

This paper motivates and develops a novel semantic framework for deontic modals. The framework is designed to shed light on two things: the relationship between deontic modals and substantive theories of practical rationality and the interaction of deontic modals with conditionals, epistemic modals and probability operators. I argue that, in order to model inferential connections between deontic modals and probability operators, we need more structure than is provided by classical intensional theories. In particular, we need probabilistic structure that (...) interacts directly with the compositional semantics of deontic modals. However, I reject theories that provide this probabilistic structure by claiming that the semantics of deontic modals is linked to the Bayesian notion of expectation. I offer a probabilistic premise semantics that explains all the data that create trouble for the rival theories. (shrink)

The focus in this essay will be upon the paradoxes, and foremostly in set theory. A central result is that the librationist set theory £ extension \Pfund $\mathscr{HR}(\mathbf{D})$ of \pounds \ accounts for \textbf{Neumann-Bernays-Gödel} set theory with the \textbf{Axiom of Choice} and \textbf{Tarski's Axiom}. Moreover, \Pfund \ succeeds with defining an impredicative manifestation set $\mathbf{W}$, \emph{die Welt}, so that \Pfund$\mathscr{H}(\mathbf{W})$ %is a model accounts for Quine's \textbf{New Foundations}. Nevertheless, the points of view developed support the view that the truth-paradoxes and (...) the set-paradoxes have common origins, so that the librationist resolutions of the set theoretic paradoxes are at the same time resolutions of the truth theoretic paradoxes. Both the librationist resolutions of the set theoretic paradoxes and the truth theoretic paradoxes have non-trivial philosophical implications: librationist set theories have the consequence that there are no absolutely uncountable sets, and librationist truth theories allow the use of syntactical modalities in ways which circumvent limitations as those of \parencite{Montague1963}, and a truth predicate which is useful for more precise philosophical discourse. (shrink)

We reply to various arguments by Otavio Bueno and Edward Zalta (‘Object Theory and Modal Meinongianism’) against Modal Meinongianism, including that it presupposes, but cannot maintain, a unique denotation for names of fictional characters, and that it is not generalizable to higher-order objects. We individuate the crucial difference between Modal Meinongianism and Object Theory in the former’s resorting to an apparatus of worlds, possible and impossible, for the representational purposes for which the latter resorts to a distinction between two kinds (...) of predication, exemplification and encoding. We show that encoding has fewer forerunners in the history of philosophy than Bueno and Zalta want, and that there’s a reason why the notion has been found baffling by some. (shrink)

The dominant conceptions of moral status in the English-speaking literature are either holist or individualist, neither of which accounts well for widespread judgments that: animals and humans both have moral status that is of the same kind but different in degree; even a severely mentally incapacitated human being has a greater moral status than an animal with identical internal properties; and a newborn infant has a greater moral status than a mid-to-late stage foetus. Holists accord no moral status to any (...) of these beings, assigning it only to groups to which they belong, while individualists such as welfarists grant an equal moral status to humans and many animals, and Kantians accord no moral status either to animals or severely mentally incapacitated humans. I argue that an underexplored, modal-relational perspective does a better job of accounting for degrees of moral status. According to modal-relationalism, something has moral status insofar as it capable of having a certain causal or intensional connection with another being. I articulate a novel instance of modal-relationalism grounded in salient sub-Saharan moral views, roughly according to which the greater a being's capacity to be part of a communal relationship with us, the greater its moral status. I then demonstrate that this new, African-based theory entails and plausibly explains the above judgments, among others, in a unified way. (shrink)

Hume thought that if you believed in powers, you believed in necessary connections in nature. He was then able to argue that there were none such because anything could follow anything else. But Hume wrong-footed his opponents. A power does not necessitate its manifestations: rather, it disposes towards them in a way that is less than necessary but more than purely contingent. -/- In this paper a dispositional theory of causation is offered. Causes dispose towards their effects and often produce (...) them. But a set of causes, even though they may succeed in producing an effect, cannot necessitate it since the effect could have been counteracted by some additional power. This would require a separation of our concepts of causal production and causal necessitation. The most conspicuous cases of causation are those where powers accumulate and pass a requisite threshold for an effect to occur. -/- We develop a model for representing powers as constituent vectors within an n-dimensional quality space, where composition of causes appears as vector addition. Even our resultant vector, however, has to be understood as having dispositional force only. This model throws new light on causal modality and cases of prevention, causation by absence and probabilistic causation. (shrink)

In this paper we define intensional models for the classical theory of types, thus arriving at an intensional type logic ITL. Intensional models generalize Henkin's general models and have a natural definition. As a class they do not validate the axiom of Extensionality. We give a cut-free sequent calculus for type theory and show completeness of this calculus with respect to the class of intensional models via a model existence theorem. After this we turn our attention to applications. Firstly, it (...) is argued that, since ITL is truly intensional, it can be used to model ascriptions of propositional attitude without predicting logical omniscience. In order to illustrate this a small fragment of English is defined and provided with an ITL semantics. Secondly, it is shown that ITL models contain certain objects that can be identified with possible worlds. Essential elements of modal logic become available within classical type theory once the axiom of Extensionality is given up. (shrink)

In his political treatise, Mabadi ara ahl al-madina al-fadhila, Abu Nasr Alfarabi, the medieval Muslim philosopher, proposes a theory of virtuous city which, according to prominent scholars, is modeled on Plato’s utopia of the Republic. No doubt that Alfarabi was well-versed in the philosophy of Plato and the basic framework of his theory of city is platonic. However, his theory of city is not an exact reproduction of the Republic’s theory and, despite glaring similarities, the two theories do (...) differ in many aspects. In both, Alfarabi’s Mabadi ara ahl al-madina al-fadhila and Plato’s Republic, the theory of virtuous city is accompanied by a theory of the soul. Since the theory of soul plays a foundational role in both theories of the virtuous city, the present article intends to provide an explanation for the differences between the two theories of the city in terms of the differences between the two theories of the soul. (shrink)

We introduce a realist, unextravagant interpretation of quantum theory that builds on the existing physical structure of the theory and allows experiments to have definite outcomes but leaves the theory’s basic dynamical content essentially intact. Much as classical systems have specific states that evolve along definite trajectories through configuration spaces, the traditional formulation of quantum theory permits assuming that closed quantum systems have specific states that evolve unitarily along definite trajectories through Hilbert spaces, and our interpretation extends this intuitive picture (...) of states and Hilbert-space trajectories to the more realistic case of open quantum systems despite the generic development of entanglement. We provide independent justification for the partial-trace operation for density matrices, reformulate wave-function collapse in terms of an underlying interpolating dynamics, derive the Born rule from deeper principles, resolve several open questions regarding ontological stability and dynamics, address a number of familiar no-go theorems, and argue that our interpretation is ultimately compatible with Lorentz invariance. Along the way, we also investigate a number of unexplored features of quantum theory, including an interesting geometrical structure—which we call subsystem space—that we believe merits further study. We conclude with a summary, a list of criteria for future work on quantum foundations, and further research directions. We include an appendix that briefly reviews the traditional Copenhagen interpretation and the measurement problem of quantum theory, as well as the instrumentalist approach and a collection of foundational theorems not otherwise discussed in the main text. (shrink)

Most elpistologists now agree that hope for a specific outcome involves more than just desire plus the presupposition that the outcome is possible. This paper argues that the additional element of hope is a disposition to focus on the desired outcome in a certain way. I first survey the debate about the nature of hope in the recent literature, offer objections to some important competing accounts, and describe and defend the view that hope involves a kind of focus or attention. (...) I then suggest that this account makes sense of the intuitive thought that there are moral and pragmatic norms on hope that go beyond the norms on desires and modal presuppositions. I conclude by considering some key questions. (shrink)

We summarize a new realist, unextravagant interpretation of quantum theory that builds on the existing physical structure of the theory and allows experiments to have definite outcomes but leaves the theory's basic dynamical content essentially intact. Much as classical systems have specific states that evolve along definite trajectories through configuration spaces, the traditional formulation of quantum theory permits assuming that closed quantum systems have specific states that evolve unitarily along definite trajectories through Hilbert spaces, and our interpretation extends this intuitive (...) picture of states and Hilbert-space trajectories to the more realistic case of open quantum systems despite the generic development of entanglement. Our interpretation—which we claim is ultimately compatible with Lorentz invariance—reformulates wave-function collapse in terms of an underlying interpolating dynamics, makes it possible to derive the Born rule from deeper principles, and resolves several open questions regarding ontological stability and dynamics. (shrink)

Our computational metaphysics group describes its use of automated reasoning tools to study Leibniz’s theory of concepts. We start with a reconstruction of Leibniz’s theory within the theory of abstract objects (henceforth ‘object theory’). Leibniz’s theory of concepts, under this reconstruction, has a non-modal algebra of concepts, a concept-containment theory of truth, and a modal metaphysics of complete individual concepts. We show how the object-theoretic reconstruction of these components of Leibniz’s theory can be represented for investigation by means of automated (...) theorem provers and finite model builders. The fundamental theorem of Leibniz’s theory is derived using these tools. (shrink)

Carnap's theory of descriptions was restricted in two ways. First, the descriptive conditions had to be non-modal. Second, only primitive predicates or the identity predicate could be used to predicate something of the descriptum . The motivating reasons for these two restrictions that can be found in the literature will be critically discussed. Both restrictions can be relaxed, but Carnap's theory can still be blamed for not dealing adequately with improper descriptions.