The term “social world” is increasingly familiar in philosophy and political theory. Rawls uses it quite often, especially in his later works. But there has been little explicit discussion of the term and the idea of social worlds. My aim in this paper is to show that political philosophers, Rawlsian or not, should think seriously about social worlds and the roles these things play and ought to play in their work. The idea of social worlds can help political philosophers think (...) about what they do in new and fruitful ways and enrich debates about the roles, aims, and methodology of political philosophy. I begin by analyzing Rawls’s uses of “social world.” I then propose a broadly Rawlsian conception of social worlds as logically possible closed networks of social relations between agents. Next, I put this conception to work, arguing that the idea of navigating the landscape of social worlds can help us better understand the four apparently disparate roles of political philosophy that Rawls presents. Moving beyond Rawls interpretation, I use the idea of social worlds to develop an analogy and distinction between world-oriented and principle-oriented approaches to political philosophy. While principle-oriented approaches grant centrality and importance to engagement with principles of justice, legitimacy, or other political concepts, world-oriented approaches grant centrality and importance to engagement with social worlds. I propose two examples of world-oriented approaches, political philosophy as navigation and political philosophy as world-building, and argue that they are viable and worthy of further consideration. (shrink)

The effects of utterances such as cue phrases, keep-turn markers, and grounding signals cannot be characterized as changes to a shared record of the propositions under discussed: the simplest (and arguably most natural) way of characterizing the meaning of these utterances is in terms of a theory in which the conversational score is seen as a record of the discourse situation, or at least of the speech acts that have been performed. The problem then becomes to explain how discourse entities (...) are accessible. We consider three hypotheses about the dynamics of a speech act-based theory of the conversational score, and argue that they could be implemented with relatively minor modifications to the technical tools already introduced in theories such as Compositional DRT. (shrink)

In this paper, I present one possible way of arguing for the theory of minimal self-consciousness, namely, by an argument by elimination. Central to the argument are the following two claims: a) If a theory of consciousness cannot explain first-person self-reference, then the theory is false, and b) An anonymity theory cannot explain first-person self-reference. Consequently, the anonymity theory is false.

Esta enciclopédia abrange, de uma forma introdutória mas desejavelmente rigorosa, uma diversidade de conceitos, temas, problemas, argumentos e teorias localizados numa área relativamente recente de estudos, os quais tem sido habitual qualificar como «estudos lógico-filosóficos». De uma forma apropriadamente genérica, e apesar de o território teórico abrangido ser extenso e de contornos por vezes difusos, podemos dizer que na área se investiga um conjunto de questões fundamentais acerca da natureza da linguagem, da mente, da cognição e do raciocínio humanos, bem (...) como questões acerca das conexões destes com a realidade não mental e extralinguística. A razão daquela qualificação é a seguinte: por um lado, a investigação em questão é qualificada como filosófica em virtude do elevado grau de generalidade e abstracção das questões examinadas (entre outras coisas); por outro, a investigação é qualificada como lógica em virtude de ser uma investigação logicamente disciplinada, no sentido de nela se fazer um uso intenso de conceitos, técnicas e métodos provenientes da disciplina de lógica. O agregado de tópicos que constitui a área de estudos lógico-filosóficos é já visível, pelo menos em parte, no Tractatus Logico-Philosophicus de Ludwig Wittgenstein, uma obra publicada em 1921. E uma boa maneira de ter uma ideia sinóptica do território disciplinar abrangido por esta enciclopédia, ou pelo menos de uma porção substancial dele, é extrair do Tractatus uma lista dos tópicos mais salientes aí discutidos; a lista incluirá certamente tópicos do seguinte género, muitos dos quais se podem encontrar ao longo desta enciclopédia: factos e estados de coisas; objectos; representação; crenças e estados mentais; pensamentos; a proposição; nomes próprios; valores de verdade e bivalência; quantificação; funções de verdade; verdade lógica; identidade; tautologia; o raciocínio matemático; a natureza da inferência; o cepticismo e o solipsismo; a indução; as constantes lógicas; a negação; a forma lógica; as leis da ciência; o número. (shrink)

This book present a unified semantic theory of expressions involving the notions of part and whole. It develops a theory of part structures which differs from traditional (extensional) mereological theories in that the notion of an integrated whole plays a central role and in that the part structure of an entity is allowed to vary across different situations, perspectives, and dimensions. The book presents a great range of empirical generalizations involving plurals, mass nouns, adnominal and adverbial modifiers such as 'whole', (...) 'together', and 'alone', nominal and adverbial quanitfiers ranging over parts, and expressions of completion such as 'completely' and 'partly'. (shrink)

Indirect speech reports can be true even if they attribute to the speaker the saying of something weaker than what she in fact expressed, yet not all weakenings of what the speaker expressed yield true reports. For example, if Anna utters ‘Bob and Carla passed the exam’, we can accurately report her as having said that Carla passed the exam, but we can not accurately report her as having said that either it rains or it does not, or that either (...) Carla passed the exam or pandas are cute. This paper offers an analysis of speech reports that distinguishes weakenings of what the speaker expressed that yield true reports from weakenings that do not. According to this analysis, speech reports are not only sensitive to the informational content of what the speaker expressed, but also to the possibilities a speaker raises in making an utterance. As I argue, this analysis has significant advantages over its most promising competitors, including views based on work by Barwise and Perry : 668–691, 1981), views appealing to recent work on the notion of content parthood by Fine :199–226, 2016) and Yablo, and Richard’s : 605–616, 1998) proposal appealing to structured propositions. (shrink)

The propositional view of communication states that every literal assertoric utterance of an indicative sentence expresses a proposition, and the audience understands those utterances only if she entertains the proposition(s) the speaker expressed. According to an important objection due to Ray Buchanan, the propositional view is ill‐equipped to handle meaning underdeterminacy. Using resources from situation semantics and MacFarlane's nonindexical contextualism, this article develops a view of literal communication close to the propositional view which overcomes Buchanan's underdeterminacy considerations while accounting for (...) the kind of indifference that typically characterizes speakers' intentions. (shrink)

'You ask me about the idiosyncrasies of philosophers? There is their lack of historical sense, their hatred of even the idea of becoming, their Egyptianism. They think they are doing a thing honour when they dehistoricize it, sub specie aeternitatis — when they make a mummy of it.'Nietzsche, Twilight of the Idols.

In this paper we suggest that differing approaches to the science of social cognition mirror the arguments between radical embodied and traditional approaches to cognition. We contrast the use in social cognition of theoretical inference and mental simulation mechanisms with approaches emphasizing a direct perception of others’ mental states. We build from a recent integrative framework unifying these divergent perspectives through the use of dual-process theory and supporting social neuroscience research. Our elaboration considers two complementary notions of direct perception: one (...) primarily stemming from ecological psychology and the other from enactive cognition theory. We use this as the foundation from which to offer an account of the informational basis for social information and assert a set of research propositions to further the science of social cognition. In doing so, we point out how perception of the minds of others can be supported in some cases by lawful information, supporting direct perception of social affordances and perhaps, mental states, and in other cases by cues that support indirect perceptual inference. Our goal is to extend accounts of social cognition by integrating advances across disciplines to provide a multi-level and multi-theoretic description that can advance this field and offer a means through which to reconcile radical embodied and traditional approaches to cognitive neuroscience. (shrink)

Here I defend dispositionalism about meaning and rule-following from Kripkenstein's infamous anti-dispositionalist arguments. The problems of finitude, error, and normativity are all addressed. The general lesson I draw is that Kripkenstein's arguments trade on an overly simplistic version of dispositionalism.

Many philosophers have argued that logical pluralism is not compatible with the normativity of logic. They developed different versions of the collapse argument: if two logics are correct, then the weaker one will be normatively irrelevant. In this paper, I argue that the collapse argument is based on a controversial premise: the assumption that every logic can be characterized by the same bridge principle. I provide a solution to the collapse argument based on the modification of this premise, maintaining both (...) logical pluralism and the normativity of logic. (shrink)

In this paper we design a new logical system to explicitly model the different deductive reasoning steps of a boundedly rational agent. We present an adequate system in line with experimental findings about an agent’s reasoning limitations and the cognitive effort that is involved. Inspired by Dynamic Epistemic Logic, we work with dynamic operators denoting explicit applications of inference rules in our logical language. Our models are supplemented by (a) impossible worlds (not closed under logical consequence), suitably structured according to (...) the effect of inference rules, and (b) quantitative components capturing the agent’s cognitive capacity and the cognitive costs of rules with respect to certain resources (e.g. memory, time). These ingredients allow us to avoid problematic logical closure principles, while at the same time deductive reasoning is reflected in our dynamic truth clauses. We further show that our models can be reduced to awareness-like plausibility structures that validate the same formulas and we give a sound and complete axiomatization with respect to them. This approach to the agent’s internal deductive reasoning is finally combined with actions of external information. (shrink)

Two main methods for analysing de re readings of definite descriptions in intensional contexts coexist: that of evaluating the description in the actual world, whether by means of scope, actuality operators, or non-local world binding, and that of substituting another description, usually one expressing a salient or ‘vivid’ acquaintance relation to an attitude holder, prior to evaluation. Recent work on so-called descriptive indexicals suggests that contrary to common assumptions, both methods are needed, for different ends. This paper aims to show (...) that there is indeed a division of labour between the two methods of analysis and to identify criteria for choosing among alternative ways to model the second, substitutional method. (shrink)

In their article entitled “Ethical Particularism and Patterns”, Frank Jackson, Philip Pettit, and Michael Smith (JPS henceforth) argue that moral particularism is a cognitively implausible theory since it appears to entail the view that one might have a skill that is not grounded in an ability to recognise and represent natural patterns in the world. This charge echoes the complaints of computational theorists of cognition against their embodied cognition counterparts, namely that, theories of cognition that eschew talk of mental representation (...) are implausible qua theories of cognition. In both debates, the cognitive role of generalisation is central to the discussion; however, contrary to the received wisdom, I want to suggest that the dispute is not between generalisation or mental representation on the one hand and no generalisation or mental representation on the other, but rather between what I will call global and local generalisation. Using the dialogue between JPS and Dancy (our paradigm particularist) to frame this discussion, I show that by replacing Dancy's connectionist model for particularist reasoning with a case-based one, we not only vindicate his response to JPS, but we also gain insight into how it is the global/local distinction rather than the generalisation/no generalisation distinction that divides the two views. (shrink)

It is generally assumed that relations of necessity cannot be known by induction on experience. In this paper, I propose a notion of situated possibilities, weaker than nomic possibilities, that is compatible with an inductivist epistemology for modalities. I show that assuming this notion, not only can relations of necessity be known by induction on our experience, but such relations cannot be any more underdetermined by experience than universal regularities. This means that any one believing in a universal regularity is (...) as well warranted to believe in the corresponding relation of necessity. (shrink)

Classical (Bayesian) probability (CP) theory has led to an influential research tradition for modeling cognitive processes. Cognitive scientists have been trained to work with CP principles for so long that it is hard even to imagine alternative ways to formalize probabilities. However, in physics, quantum probability (QP) theory has been the dominant probabilistic approach for nearly 100 years. Could QP theory provide us with any advantages in cognitive modeling as well? Note first that both CP and QP theory share the (...) fundamental assumption that it is possible to model cognition on the basis of formal, probabilistic principles. But why consider a QP approach? The answers are that (1) there are many well-established empirical findings (e.g., from the influential Tversky, Kahneman research tradition) that are hard to reconcile with CP principles; and (2) these same findings have natural and straightforward explanations with quantum principles. In QP theory, probabilistic assessment is often strongly context- and order-dependent, individual states can be superposition states (that are impossible to associate with specific values), and composite systems can be entangled (they cannot be decomposed into their subsystems). All these characteristics appear perplexing from a classical perspective. However, our thesis is that they provide a more accurate and powerful account of certain cognitive processes. We first introduce QP theory and illustrate its application with psychological examples. We then review empirical findings that motivate the use of quantum theory in cognitive theory, but also discuss ways in which QP and CP theories converge. Finally, we consider the implications of a QP theory approach to cognition for human rationality. (shrink)

What are the objects of speaker meaning? The traditional answer is: propositions. The traditional answer faces an important challenge: if propositions are the objects of speaker meaning then there must be specific propositions that speakers intend their audiences to recover. Yet, speakers typically exhibit a degree of indifference regarding how they are interpreted, and cannot rationally intend for their audiences to recover specific propositions. Therefore, propositions are not the objects of speaker meaning (Buchanan 2010; MacFarlane 2020a; 2020b; and Abreu Zavaleta (...) 2021). In this paper I do two things. Firstly, I outline a collective analogue of this challenge that undermines the most prominent responses to the original challenge. Secondly, I provide a new solution: typical utterances are backed by a cluster of partial communicative intentions. This response resolves both individual and collective variants of the problem and allows us to retain the traditional propositional view of speaker meaning. (shrink)

Quine and Davidson employ proxy functions to demonstrate that the use of language (behaviouristically conceived) is compatible with indefinitely many radically different reference relations. They also believe that the use of language (behaviouristically conceived) is all that determines reference. From this they infer that reference is indeterminate, i.e. that there are no facts of the matter as to what singular terms designate and what predicates apply to. Yet referential indeterminacy yields rather dire consequences. One thus does wonder whether one can (...) hold on to a Quine--Davidson stance in semantics-cum-metaphysics and still avoid embracing referential indeterminacy. I argue that one can. Anyone adhering to the behaviouristic account pivotal to the Quine--Davidson stance is bound to acknowledge certain facts about verbal behaviour -- that some utterances are tied to situations, that some utterances are tied to segments in situations, that some predicates have non-contextualised conditions of application, and that use involves causal dependencies. The restrictions from these facts ensure that only reference relations generated by means of rather exceptional proxy functions are compatible with verbal behaviour. I conclude that this allows one to rebuff the Quine--Davidson argument for the indeterminacy of reference, as it were, from within. I moreover tentatively conclude that the line of thought laid out provides good reason for just about anyone to hold that there are facts about reference after all. (shrink)

A widely shared view in the literature on first-person thought is that the ability to entertain first-person thoughts requires prior non-conceptual forms of self-consciousness. Many philosophers maintain that the distinctive awareness which accompanies the use of the first person already presupposes a non-conceptual consciousness of the fact that oneself is the owner of a first-person thought. I call this argument The Argument for Non-Conceptual Self-Consciousness based on the Meaning of “I” and will demonstrate that most proponents of the presented argument (...) fail to establish their conclusion, even though I believe that the conclusion is actually true. The argument only justifies the claim that contextual information is needed in order to recognize oneself as the referent of an occurrence of the first person. However, it does not justify the thesis that this information needs to be given consciously and thus the existence of any non-conceptual self-consciousness. Finally, I shall present an argument for the assumption that some form of self-consciousness is needed to reflexively think about oneself via the first-person concept. In order to do so, I will draw on the general discussion about the functional role of consciousness. In particular, I will rely on results recently proposed by Frith and Metzinger (2016), Frith (Pragmatics & Cognition 18:497–551, 2010, Cognitive Neuroscience 2:117–118, 2011), Graziano (2013, Frontiers in Robotics and AI 4:article 60, 2017), and Graziano and Kastner (Cognitive Neuroscience 2:98–113, 2011), which suggest that one of the central functions of consciousness is to provide information about mental states for communication. (shrink)

Despite its enormous popularity, Russell’s theory of definite descriptions has received various criticisms. Two of the most important objections against this theory are those arising from the Argument from Incompleteness and the Argument from Donnellan’s Distinction. According to the former although a speaker may say something true by assertively uttering a sentence containing an incomplete description , on the Russellian analysis such a sentence expresses a false proposition; so, Russell’s theory cannot adequately deal with such sentences. According to the latter (...) objection a descriptive sentence is actually ambiguous—it expresses a general proposition when the description contained in it is used attributively, and a singular proposition when the description in question is used referentially; Russell’s theory is inadequate as it fails to capture this ambiguity and offers an analysis according to which a descriptive sentence expresses only a general proposition. These objections are examined in the present dissertation. It is shown here that these objections arise from: (i) ignoring the distinction between the meaning of a sentence and the assertions made by using it, (ii) the failure to distinguish between the semantic meaning of a sentence and the pragmatic meaning with which it is used on a particular occasion. To make the distinction mentioned in (i), a significant part of Scott Soames’ theory concerning meaning and assertions has been adopted in this dissertation; and, to make the distinction mentioned in (ii), a test, namely the cancellability test, and two Distinguishing Criteria, namely DC-1 and DC-2, have been developed here. It has been argued here that if we properly make the relevant distinctions, then we will find that: (a) the phenomenon cited by the Argument from Incompleteness can be well explained keeping the Russellian analysis of descriptive sentences intact, (b) the phenomenon arising from the Argument from Donnellan’s Distinction raises an issue of pragmatics and is irrelevant to Russell’s semantic analysis of descriptive sentences. So, none of the above criticisms poses a genuine threat to Russell’s theory of definite descriptions; his theory actually provides, to a large extent, a correct semantic analysis of descriptive sentences. (shrink)

In this paper we consider the theory of predicate logics in which the principle of Bivalence or the principle of Non-Contradiction or both fail. Such logics are partial or paraconsistent or both. We consider sequent calculi for these logics and prove Model Existence. For L4, the most general logic under consideration, we also prove a version of the Craig-Lyndon Interpolation Theorem. The paper shows that many techniques used for classical predicate logic generalise to partial and paraconsistent logics once the right (...) set-up is chosen. Our logic L4 has a semantics that also underlies Belnap’s [4] and is related to the logic of bilattices. L4 is in focus most of the time, but it is also shown how results obtained for L4 can be transferred to several variants. (shrink)

This paper developes a relational---as opposed to a functional---theory of types. The theory is based on Hilbert and Bernays' eta operator plus the identity symbol, from which Church's lambda and the other usual operators are then defined. The logic is intended for use in the semantics of natural language.

Arguments against the Russellian theory of definite descriptions based on cases that involve failures of uniqueness are a recurrent theme in the relevant literature. In this paper, I discuss a number of such arguments, from Strawson (1950), Ramachandran (1993) and Szabo (2005). I argue that the Russellian has resources to account for these data by deploying a variety of mechanisms of quantifier domain restrictions. Finally, I present a case that is more problematic for the Russellian. While the previous cases all (...) involve referential uses of descriptions (or some variations of such uses), the most effective objection to the uniqueness condition draws on genuine attributive uses. (shrink)

Points of view are a central phenomenon in human cognition. Although the concept of point of view is ambiguous, there exist common elements in different notions. A point of view is a certain way to look at things around us. In conceptual points of view, things are looked at or interpreted through conceptual lenses. Conceptual points of view are important for epistemology, cognitive science, and philosophy of science. In this article, a new method to formalize conceptual points of view is (...) introduced. It is based on the conceptual space approach, where concepts are regions of multi-dimensional quality spaces. Points of view, as defined in this article, consist of a selection of relevant dimensions, referred to here as determinables, and of a certain supposition, referred to here as a theory, about the subject content. After considering some early efforts to formalize points of view, the notion of conceptual space is defined and explored. One concept of point of view is defined and developed in the framework of conceptual space, and a new logic for points of view is also outlined. The problem of mind–body correlation is discussed as an example of the application of the notion of points of view. To conclude, the meaning and applications of the new concepts and tools developed in the article are discussed. (shrink)

Within AI and the cognitively related disciplines, there exist a multiplicity of uses of belief. On the face of it, these differing uses reflect differing views about the nature of an objective phenomenon called belief. In this paper I distinguish six distinct ways in which belief is used in AI. I shall argue that not all these uses reflect a difference of opinion about an objective feature of reality. Rather, in some cases, the differing uses reflect differing concerns with special (...) AI applications. In other cases, however, genuine differences exist about the nature of what we pre-theoretically call belief. To an extent the multiplicity of opinions about, and uses of belief, echoes the discrepant motivations of AI researchers. The relevance of this discussion for cognitive scientists and philosophers arises from the fact that (a) many regard theoretical research within AI as a branch of cognitive science, and (b) even if theoretical AI is not cognitive science, trends within AI influence theories developed within cognitive science. It should be beneficial, therefore, to unravel the distinct uses and motivations surrounding belief, in order to discover which usages merely reflect differing pragmatic concerns, and which usages genuinely reflect divergent views about reality. (shrink)

I discuss Lawlor’s Austinian account of knowledge ascriptions and argue that it is a brand of pragmatic encroachment. I then criticize the motivation for pragmatic encroachment theories that derives from assumptions about the functional role of knowledge ascriptions. I argue that this criticism also apply to contextualist followers of Craig. Finally, I suggest that the central lesson from reflection on the communicative functions of knowledge ascriptions is that they, upon reflection, motivate traditional invariantism.

According to John McDowell, in its central uses, ‘I’ is immune to error through misidentification and thus to be accounted strongly identification‐free (I–II). Neither doctrine is obviously well founded (III); indeed, given that deixis is a proper part of ‘I’ (IV–VIII), it appears that uses of ‘I’ are identification‐dependent (IX–X).

Game theoretic pragmatics is a small but growing part of formal pragmatics, the linguistic subfield studying language use. The general logic of a game theoretic explanation of a pragmatic phenomenon is this: the conversational context is modelled as a game between speaker and hearer; an adequate solution concept then selects the to‐be‐explained behavior in the game model. For such an explanation to be convincing, both components, game model and solution concept, should be formulated and scrutinized as explicitly as possible. The (...) article demonstrates this by a concise overview of both evolutionary and non‐evolutionary approaches to game theoretic pragmatics, arguing for the use of agent‐based micro‐dynamics within evolutionary, and for the use of epistemic game theory within non‐evolutionary approaches. (shrink)

It's a presupposition of a very common way of thinking about contextsensitivity in language that the semantic contribution made by a bit of context-sensitive vocabulary is sensitive only to features of the speaker's situation at the time of utterance. I argue that this is false, and that we need a theory of context-dependence that allows for content to depend not just on the features of the utterance's origin, but also on features of its destination. There are cases in which a (...) single utterance semantically conveys different propositions to different members of its audience, which force us to say that what a sentence conveys depends not just on the context in which it is uttered, but also on the context in which it is received. (shrink)

The reductionist/holist debate seems an impoverished one, with many participants appearing to adopt a position first and constructing rationalisations second. Here I propose an intermediate position of pragmatic holism, that irrespective of whether all natural systems are theoretically reducible, for many systems it is completely impractical to attempt such a reduction, also that regardless if whether irreducible `wholes' exist, it is vain to try and prove this in absolute terms. This position thus illuminates the debate along new pragmatic lines, and (...) refocusses attention on the underlying heuristics of learning about the natural world. (shrink)

How good are we at understanding what others communicate? It often seems to us, at least, that we understand quite well what others convey when speaking in a familiar language. However, a growing body of evidence from the psychology of language suggests that in various communicative settings comprehenders routinely form linguistic representations that are underdetermined, “sketchy”, “shallow” or imprecise, often without noticing it. The paper discusses some important consequences of this evidence. Following recent discussions in this strand of research, I (...) outline how the evidence is currently best interpreted as supporting a view on which operating at a certain level of imprecision and underdetermination is a functional feature of the system responsible for comprehension of linguistic utterances in humans. That this kind of imprecision and underdetermination is part and parcel of linguistic interactions, makes the exact success rate of comprehension particularly hard to estimate. This poses a unique and interesting challenge for assessing the quality of linguistic comprehension. Understanding what a speaker intended to convey with a linguistic utterance may be less transparent than it appears to us. I will discuss the extent to which this evidence may lead to pessimism about how good we are at comprehending what others communicate. However, as I will argue in the last part of the paper, in various cases language users can be sensitive to some types of imprecision and underdetermination in comprehension and make up for it by means of various forms of post hoc deliberation. I will describe some such clarificatory contexts and end by charting a map of important issues that require further investigation. (shrink)

Forthcoming in Philosophical Issues, vol 18, Interdisciplinary Core Philosophy: The Metaphysics and Perception of Qualities. Alex Byrne & David Hilbert, section editors.

In this paper, we address the question of how an agent can guide its behavior with respect to aspects of the sociomaterial environment that are not sensorily present. A simple example is how an animal can relate to a food source while only sensing a pheromone, or how an agent can relate to beer, while only the refrigerator is directly sensorily present. Certain cases in which something is absent have been characterized by others as requiring ‘higher’ cognition. An example of (...) this is how during the design process architects can let themselves be guided by the future behavior of visitors to an exhibit they are planning. The main question is what the sociomaterial environment and the skilled agent are like, such that they can relate to each other in these ways. We argue that this requires an account of the regularities in the environment. Introducing the notion of general ecological information, we will give an account of these regularities in terms of constraints, information and the form of life or ecological niche. In the first part of the paper, we will introduce the skilled intentionality framework as conceptualizing a special case of an animal’s informational coupling with the environment namely skilled action. We will show how skilled agents can pick up on the regularities in the environment and let their behavior be guided by the practices in the form of life. This conceptual framework is important for radical embodied and enactive cognitive science, because it allows these increasingly influential paradigms to extend their reach to forms of ‘higher’ cognition such as long-term planning and imagination. (shrink)

I propose a novel hyperintensional semantics for belief revision and a corresponding system of dynamic doxastic logic. The main goal of the framework is to reduce some of the idealisations that are common in the belief revision literature and in dynamic epistemic logic. The models of the new framework are primarily based on potentially incomplete or inconsistent collections of information, represented by situations in a situation space. I propose that by shifting the representational focus of doxastic models from belief sets (...) to collections of information, and by defining changes of beliefs as artifacts of changes of information, we can achieve a more realistic account of belief representation and belief change. The proposed dynamic operation suggests a non-classical way of changing beliefs: belief revision occurs in non-explosive environments which allow for a non-monotonic and hyperintensional belief dynamics. A logic that is sound with respect to the semantics is also provided. (shrink)

I propose a comprehensive account of negation as a modal operator, vindicating a moderate logical pluralism. Negation is taken as a quantifier on worlds, restricted by an accessibility relation encoding the basic concept of compatibility. This latter captures the core meaning of the operator. While some candidate negations are then ruled out as violating plausible constraints on compatibility, different specifications of the notion of world support different logical conducts for negations. The approach unifies in a philosophically motivated picture the following (...) results: nothing can be called a negation properly if it does not satisfy Contraposition and Double Negation Introduction; the pair consisting of two split or Galois negations encodes a distinction without a difference; some paraconsistent negations also fail to count as real negations, but others may; intuitionistic negation qualifies as real negation, and classical Boolean negation does as well, to the extent that constructivist and paraconsistent doubts on it do not turn on the basic concept of compatibility but rather on the interpretation of worlds. (shrink)