We need to understand the impossible. Francesco Berto and Mark Jago start by considering what the concepts of meaning, information, knowledge, belief, fiction, conditionality, and counterfactual supposition have in common. They are all concepts which divide the world up more finely than logic does. Logically equivalent sentences may carry different meanings and information and may differ in how they're believed. Fictions can be inconsistent yet meaningful. We can suppose impossible things without collapsing into total incoherence. Yet for the leading philosophical (...) theories of meaning, these phenomena are an unfathomable mystery. To understand these concepts, we need a metaphysical, logical, and conceptual grasp of situations that could not possibly exist: Impossible Worlds. This book discusses the metaphysics of impossible worlds and applies the concept to a range of central topics and open issues in logic, semantics, and philosophy. It considers problems in the logic of knowledge, the meaning of alternative logics, models of imagination and mental simulation, the theory of information, truth in fiction, the meaning of conditional statements, and reasoning about the impossible. In all these cases, impossible worlds have an essential role to play. (shrink)

endorsed one kind of inverted spectrum hypothesis and rejected another. This paper argues that the kind of inverted spectrum hypothesis that Wittgenstein endorsed is the thin end of the wedge that precludes a Wittgensteinian critique of the kind of inverted spectrum hypothesis he rejected. The danger of the dangerous kind is that it provides an argument for qualia, where qualia are contents of experiential states which cannot be fully captured in natural language. I will pinpoint the difference between the innocuous (...) and dangerous scenarios that matters for the argument for qualia, give arguments in favor of the coherence and possibility of the dangerous scenario, and try to show that some standard arguments against inverted spectra are ineffective against the version of the dangerous scenario I will be advocating. The leading idea of the paper is that an argument for qualia based on spectrum inversion does not require that the inversion be behaviorally indistinguishable. At one crucial point, I will rely on a less controversial version of an argument I gave in Block. Wittgenstein's views provide a convenient starting point for a paper that is much more about qualia than about Wittgenstein. (shrink)

I lay out the framework for my theory of sensory imagination in “Imagining as a guide to possibility.” Sensory imagining involves mental imagery , and crucially, in describing the content of imagining, I distinguish between qualitative content and assigned content. Qualitative content derives from the mental image itself; for visual imaginings, it is what is “pictured.” For example, visually imagine the Philadelphia Eagles defeating the Pittsburgh Steelers to win their first Super Bowl. You picture the greenness of the field and (...) the football’s brown oblong shape. Some of what you imagine isn’t explicitly pictured, however. That it is Sunday, that it is the Super Bowl: these facts are assigned. (shrink)

The philosophy of necessity and possibility has flourished in the last half-century, but much less attention has been paid to the question of how we know what can be the case and what must be the case. Many friends of modal metaphysics and many enemies of modal metaphysics have agreed that while empirical discoveries can tell us what is the case, they cannot shed much light on what must be the case or on what non-actual possibilities there are. In this (...) paper, in contrast, I discuss and defend naturalistic approaches to discovering the facts about necessity and possibility. After some remarks about what methodological naturalism in philosophy might amount to, I argue that naturalistic method in modal investigations may not need to be particularly revisionary of much of what is currently being done in modal investigation. I then discuss a number of respects in which a naturalistic orientation in modal investigation may improve on our current epistemic situation. (shrink)

This is the introduction to the Routledge Companion to Thought Experiments.

This dissertation concerns the foundations of epistemic modality. I examine the nature of epistemic modality, when the modal operator is interpreted as concerning both apriority and conceivability, as well as states of knowledge and belief. The dissertation demonstrates how phenomenal consciousness and gradational possible-worlds models in Bayesian perceptual psychology relate to epistemic modal space. The dissertation demonstrates, then, how epistemic modality relates to the computational theory of mind; metaphysical modality; deontic modality; logical modality; the types of mathematical modality; to the (...) epistemic status of undecidable propositions and abstraction principles in the philosophy of mathematics; to the apriori-aposteriori distinction; to the modal profile of rational propositional intuition; and to the types of intention, when the latter is interpreted as a modal mental state. Examining the nature of epistemic logic itself, I develop a novel approach to conditions of self-knowledge in the setting of the modal μ-calculus, as well as novel epistemicist solutions to Curry's, the liar, and the knowability paradoxes. Solutions to previously intransigent issues concerning the first-person concept; the distinction between fundamental and derivative truths; and the unity of intention and its role in decision theory, are developed along the way. (shrink)

Abstract Timothy Williamson has recently proposed to undermine modal skepticism by appealing to the reducibility of modal to counterfactual logic ( Reducibility ). Central to Williamson’s strategy is the claim that use of the same non-deductive mode of inference ( counterfactual development , or CD ) whereby we typically arrive at knowledge of counterfactuals suffices for arriving at knowledge of metaphysical necessity via Reducibility. Granting Reducibility, I ask whether the use of CD plays any essential role in a Reducibility-based reply (...) to two kinds of modal skepticism. I argue that its use is entirely dispensable, and that Reducibility makes available replies to modal skeptics which show certain propositions to be metaphysically necessary by deductive arguments from premises the modal skeptic accepts can be known. Content Type Journal Article Pages 1-19 DOI 10.1007/s11098-011-9784-4 Authors Juhani Yli-Vakkuri, Wolfson College, Oxford University, Oxford, OX2 6UD UK Journal Philosophical Studies Online ISSN 1573-0883 Print ISSN 0031-8116. (shrink)

A modest transcendental argument is one that sets out merely to establish how things need to appear to us or how we need to believe them to be, rather than how things are. Stroud's claim to have established that all transcendental arguments must be modest in this way is criticised and rejected. However, a different case for why we should abandon ambitious transcendental arguments is presented: namely, that when it comes to establishing claims about how things are, there is no (...) reason to prefer transcendental arguments to arguments that rely on the evidence of the senses, making the former redundant in a way that modest transcendental arguments, which have a different kind of sceptical target, are not. (shrink)

I discuss the relation between egocentric spatial representation and the capacity for bodily activity, with specific reference to Merleau-Ponty.

Following the standard practice in sociology, cultural anthropology and history, sociologists, historians of science and some philosophers of science define scientific communities as groups with shared beliefs, values and practices. In this paper it is argued that in real cases the beliefs of the members of such communities often vary significantly in important ways. This has rather dire implications for the convergence defense against the charge of the excessive subjectivity of subjective Bayesianism because that defense requires that communities of Bayesian (...) inquirers share a significant set of modal beliefs. The important implication is then that given the actual variation in modal beliefs across individuals, either Bayesians cannot claim that actual theories have been objectively confirmed or they must accept that such theories have been confirmed relative only to epistemically insignificant communities. (shrink)

My aim in this paper is to give a philosophical analysis of the relationship between contingently available technology and the knowledge that it makes possible. My concern is with what specific subjects can know in practice, given their particular conditions, especially available technology, rather than what can be known “in principle” by a hypothetical entity like Laplace’s Demon. The argument has two parts. In the first, I’ll construct a novel account of epistemic possibility that incorporates two pragmatic conditions: responsibility and (...) practicability. For example, whether subjects can gain knowledge depends in some circumstances on whether they have the capability of gathering relevant evidence. In turn, the possibility of undertaking such investigative activities depends in part on factors like ethical constraints, economical realities, and available technology. In the second part of the paper, I’ll introduce “technological possibility” to analyze the set of actions made possible by available technology. To help motivate the problem and later test my proposal, I’ll focus on a specific historical case, one of the earliest uses of digital electronic computers in a scientific investigation. I conclude that the epistemic possibility of gaining access to scientific knowledge about certain subjects depends (in some cases) on the technological possibility for making responsible investigations. (shrink)

The paper explores the project of an ambitious modal epistemology that attempts to combine the a priori methods of Chalmers’ 2D semantics with Kripke’s modal metaphysics. I argue that such a project is not viable. The ambitious modal epistemology involves an inconsistent triad composed of (1) Modal Monism, (2) Two-Dimensionalism, and what I call (3) “Metaphysical Kripkeanism”. I present the three theses and show how only two of those can be true at a time. There is a fundamental incompatibility between (...) Chalmers’ Modal Rationalism and Kripke’s modal metaphysics. Specifically, Chalmers’ conceivability entails possibilities that a Kripkean rejects as genuinely metaphysical. However, three positive stances in modal epistemology emerge from the combinations that the triad allows. One of those offers a promising way forward for 2D modal epistemologies. But it comes with a cost, as it requires abandoning modal monism and reshaping the scope of what a priori conceivability can give us access to. (shrink)

In, the author proposes a survey of Zalta’s Object Theory and, more specifically, of the Modal Axiom of Encoding. MAE claims that if something x possibly encodes a property F, then x necessarily encodes F. According to Bourgeois-Gironde, MAE fails to account for intentional phenomena which occur in conceivability-contexts. His solution is based on the notion of quasi-encoding: x quasi-encodes F iff x possibly encodes F. In this paper, I show that Bourgeois-Gironde’s concern is misguided and that Zalta’s framework captures (...) the conceivability-phenomena at issue by modeling Husserl’s notion of Noemata. I then argue that his solution is superior to Bourgeois-Gironde’s. The philosophical significance of such a discussion nonetheless goes well beyond the debate between these two authors. Indeed, Zalta’s theory of Noemata is only sketched and needs to be further explored to see, on the one hand, whether and how Object Theory successfully describes the behavior of objects in conceivability-contexts, and, on the other hand, to test the efficacy of its primitive notions that are – as the contemporary debate on Neomeinongianism largely shows – anything but uncontroversial. (shrink)

It is standard practice in philosophical inquiry to test a general thesis (of the form 'F iff G' or 'F only if G') by attempting to construct a counterexample to it. If we can imagine or conceive of1an F that isn't a G, then we have evidence that there could be an F that isn't a G — and thus evidence against the thesis in question; if not, then the thesis is (at least temporarily) secure. Or so it is standardly (...) claimed.But there is increasing skepticism about how seriously to take what we can imagine or conceive as evidence for (or against) a priori philosophical theses, given the many historical examples of now-questionable theses that once seemed impossible to doubt — and also the recent experimental research .. (shrink)

I know that I could have been where you are right now and that you could have been where I am right now, but that neither of us could have been turnips or natural numbers. This knowledge of metaphysical modality stands in need of explanation. I will offer an account based on our knowledge of the natures, or essencess, of things. I will argue that essences need not be viewed as metaphysically bizarre entities; that we can conceptualise and refer to (...) essences; and that we can gain knowledge of them. We can know about which properties are, and which properties are not, essential to a given entity. This knowledge of essence offers a route to knowledge of the ways those entities must be or could be. (shrink)

What sorts of things are the intuitions generated via thought experiment? Timothy Williamson has responded to naturalistic skeptics by arguing that thought-experiment intuitions are judgments of ordinary counterfactuals. On this view, the intuition is naturalistically innocuous, but it has a contingent content and could be known at best a posteriori. We suggest an alternative to Williamson's account, according to which we apprehend thought-experiment intuitions through our grasp on truth in fiction. On our view, intuitions like the Gettier intuition are necessarily (...) true and knowable a priori. Our view, like Williamson's, avoids naturalistic skepticism. (shrink)

I argue that it is possible, in the right circumstances, to see what the kind thing is to do: in the right circumstances, we can, literally, see deontic facts, as well as facts about others’ emotional states, and evaluative facts. In arguing for this, I will deploy a notion of non‐inferential perceptual belief or judgement according to which the belief or judgement is arrived at non‐inferentially in the phenomenological sense and yet is inferential in the epistemic sense. The ability to (...) arrive at these kinds of beliefs and judgements is part of virtue, and is also part of what it is to grasp thick ethical concepts in an engaged way. When we come to thinner evaluative and deontic facts and thinner ethical concepts, however, the requirements for non‐inferential perceptual belief and judgement are less easily met. Seeing what is the kind thing to do is one matter; seeing what is the right thing to do is another. (shrink)

This article argues for two related theses. First, it defends a general thesis: any kind of necessity, including metaphysical necessity, can only be known a priori. Second, however, it also argues that the sort of a priori involved in modal metaphysical knowledge is not related to imagination or any sort of so-called epistemic possibility. Imagination is neither a proof of possibility nor a limit to necessity. Rather, modal metaphysical knowledge is built on intuition of philosophical categories and the structures they (...) form. (shrink)

Bullot & Reber (B&R) put forth a design stance to fuse psychological and art historical accounts of visual thinking into a single theory. We argue that this aspect of their proposal needs further fine-tuning. Issues of transgression and coherence are necessary to provide stability to the design stance. We advocate looking to Art Education for such fundamentals of picture understanding.

The negative zombie argument concludes that physicalism is false from the premises that p ∧¬q is ideally negatively conceivable and that what is ideally negatively conceivable is possible, where p is the conjunction of the fundamental physical truths and laws and q is a phenomenal truth (Chalmers 2002; 2010). A sentence φ is ideally negatively conceivable iff φ is not ruled out a priori on ideal rational reflection. In this paper, I argue that the negative zombie argument is neither a (...) priori nor conclusive. First, I argue that the premises of the argument are true only if there exists an adequate finite ideal reasoner R that believes ◊(p ∧ ¬q) on the basis of not believing p→q on a priori basis. Roughly, a finite reasoner is a reasoner with cognitive limitations (e.g. finite memory). I argue that R is finite only if R reasons nonmonotonically and only approach ideal reflection at the limit of a reasoning sequence. This would render the argument nonconclusive. Finally, I argue that, for some q, R does not believe ◊(p ∧ ¬q) on the basis of not believing p→q on a priori basis (e.g. for q =‘something is conscious’). This would render the choice of an adequate q dependent on empirical information (and the argument a posteriori). I conclude that the negative zombie argument (and, maybe, all zombie arguments) is neither a priori nor conclusive. (shrink)

The Humean view that conceivability entails possibility can be criticized via input from cognitive psychology. A mainstream view here has it that there are two candidate codings for mental representations (one of them being, according to some, reducible to the other): the linguistic and the pictorial, the difference between the two consisting in the degree of arbitrariness of the representation relation. If the conceivability of P at issue for Humeans involves the having of a linguistic mental representation, then it is (...) easy to show that we can conceive the impossible, for impossibilities can be represented by meaningful bits of language. If the conceivability of P amounts to the pictorial imaginability of a situation verifying P, then the question is whether the imagination at issue works purely qualitatively, that is, only by phenomenological resemblance with the imagined scenario. If so, the range of situations imaginable in this way is too limited to have a significant role in modal epistemology. If not, imagination will involve some arbitrary labeling component, which turns out to be sufficient for imagining the impossible. And if the relevant imagination is neither linguistic nor pictorial, Humeans will appear to resort to some representational magic, until they come up with a theory of a ‘third code’ for mental representations. (shrink)

I present a formal theory of the logic and aboutness of imagination. Aboutness is understood as the relation between meaningful items and what they concern, as per Yablo and Fine’s works on the notion. Imagination is understood as per Chalmers’ positive conceivability: the intentional state of a subject who conceives that p by imagining a situation—a configuration of objects and properties—verifying p. So far aboutness theory has been developed mainly for linguistic representation, but it is natural to extend it to (...) intentional states. The proposed framework combines a modal semantics with a mereology of contents: imagination operators are understood as variably strict quantifiers over worlds with a content-preservation constraint. (shrink)

What role does the imagination play in scientific progress? After examining several studies in cognitive science, I argue that one thing the imagination does is help to increase scientific understanding, which is itself indispensable for scientific progress. Then, I sketch a transcendental justification of the role of imagination in this process.

The dissertation is in the format of a collection of several academic texts, composed of a two-part presentation and three papers on the topic of conceivability and the epistemology of modality. The presentation is composed of, first, a general introduction to conceivability theses and objections and, second, a discussion of two cases. Following the presentation, Asger provides three papers. The first paper, Pretense and Conceivability: A reply to Roca-Royes, presents a problem and a dilemma for Roca-Royes’ Non-Standard Dilemma for conceivability-based (...) epistemologies of de re modality in which she concludes that conceivability cannot be the whole story of our de re modal knowledge. The second paper, Conceivability Externalized, proposes an externalist conceivability-based epistemology of possibility inspired by Stalnaker. The third paper, Inconceivability as a Guide to Impossibility, considers inconceivability as an epistemic guide to impossibility, aiming to explore and add support to the underexplored thesis that one can justify beliefs about the impossibility of P on the basis of the inconceivability of P. (shrink)

Qualia inversion thought experiments are ubiquitous in contemporary philosophy of mind. The most popular kind is one or another variant of Locke's hypothetical case of.

The development of possible worlds semantics for modal claims has led to a more general application of that theory as a complete semantics for various formal and natural languages, and this view is widely held to be an adequate (philosophical) interpretation of the model theory for such languages. We argue here that this view generates a self-referential inconsistency that indicates either the falsity or the incompleteness of PWS.

The notion of an ideal reasoner has several uses in epistemology. Often, ideal reasoners are used as a parameter of (maximum) rationality for finite reasoners (e.g. humans). However, the notion of an ideal reasoner is normally construed in such a high degree of idealization (e.g. infinite/unbounded memory) that this use is unadvised. In this dissertation, I investigate the conditions under which an ideal reasoner may be used as a parameter of rationality for finite reasoners. In addition, I present and justify (...) the research program of computational epistemology, which investigates the parameter of maximum rationality for finite reasoners using computer simulations. (shrink)

Theory and Reality is about the connection between true theories and the world. A mathematical framefork for such connections is given, and it is shown how that framework can be used to infer facts about the structure of reality from facts about the structure of true theories, The book starts with an overview of various approaches to metaphysics. Beginning with Quine's programmatic "On what there is", the first chapter then discusses the perils involved in going from language to metaphysics. It (...) criticises contemporary intuition-driven metaphysics, comments on naturalistic approaches, and then presents the main proposition put forward in the thesis: we should base metaphysics on model theory. In chapters 2 to 5, mathematical treatments are given of concepts that we need: theories, metaphysics, necessitation and semantics. These are used in chapters 6 and 7 to prove that, seen from a certain informative view point, any true theory will give rise to an isomorphism between that theory and the world. This conclusion is similar to Wittgenstein's in the Tractatus, but differs in that it places the structural relationship on the level of whole theories, rather than single propositions. (shrink)

Externalist theories in natural language semantics have become the orthodoxy since Kripke is widely thought to have refuted descriptive theories involving internal cognitive representation of meaning. This shift may be seen in developments in philosophy of language of the 1970s – the direct reference “revolution against Frege”. I consider Fodor’s heretical thought that something has gone “awfully wrong” in this philosophical consensus, perhaps confirming Chomsky’s view that the whole field of philosophical semantics is “utterly wrongheaded” and “crazy” by virtue of (...) its non-naturalist assumptions and “methodological dualism.” Kripke acknowledges that he was led to his views by his “natural intuition”. Accordingly, I take up the aetiological question Chomsky poses, suggesting that we may go beyond the usual analysis of those doctrines that have been assumed too uncritically “to ask why they seem so compelling”. I suggest that the externalist orthodoxy is a kind of cognitive illusion seen elsewhere in philosophy and cognitive science. (shrink)

This chapter sketches what is considered the best interpretation of physicalism, rehearses the best way of defending it, and shows that the physicalism forthcoming is still going to be less than fully satisfying; it is going to leave us short of the satisfaction that might be expected from a philosophical theory. The chapter is organized into three sections. The first section gives an interpretation of physicalism in the spirit of Frank Jackson's; this involves a rich version under which the way (...) things are phenomenally is derivable in principle from physical premisses. The second sketches a representationalist or intentionalist argument for physicalism about phenomenal experience, one which also appeals to Jackson. The third section argues that even if we accept this case for a rich physicalism, still we should not expect to find the doctrine fully satisfying; the simulatory gap will stand between us and a sort of satisfaction that we might have expected to achieve. (shrink)

What is the relationship between pain and the body? I claim that pain is best explained as a type of personal experience and the bodily response during pain is best explained in terms of a type of mechanical neurophysiologic operation. I apply the radical philosophy of identity theory from philosophy of mind to the relationship between the personal experience of pain and specific neurophysiologic mechanism and argue that the relationship between them is best explained as one of type identity. Specifically, (...) pain is a specific type of personal experience identical to a specific type of allostatic stress response comprised of interdependent nervous, endocrine and immune mechanical operations. (shrink)

The broad aim of this thesis is to explore fruitful connections between ideology theory and the philosophy of possible worlds. Ideologies are full of modal concepts, such as possibility, potential, necessity, essence, contingency and accident. Typically, PWs are articulated for the analysis and illumination of modal concepts. That naturally suggests a method for theorising ideological modality, utilising PW theory. The specific conclusions of the thesis proffer a number of original contributions to knowledge: 1) PWs should only be used for explication (...) and not as evidence or criteria of assessment in ideology theory. The estimation of utopian possibilities, human essences and freedoms must be determined by extrinsic criteria. PWs can serve only as a window or means of expression but not as a set of evaluative premises. 2) For this purpose, a modified version of Lewisian genuine realism, with its device of counterpart theory, is the best approach; the alternative theories risk constricting possibilities or smuggling in assumptions that ought to be objects of analysis in ideology theory. This is instructive, since ideology theorists are prone to pick and choose favoured aspects of modal philosophy without further argument. 3) Conclusions and suggest the adoption of GR or fictionalist GR. Overall, the actualist options are less adequate. Fictionalism, by contrast, is a worthwhile contender, but it too presents comparative weaknesses which reinforce GR’s standing as a potent challenger to the modal metaphysician. Therefore, this thesis presents additional reasons to think GR true. The conclusions are not knockdown, and I draw out incentives and consequences for adopting alternative stances. The various chapters also provide specific details for comprehending and debating ideological modals. (shrink)

The purpose of this thesis is to demonstrate that metaphysics is a necessary discipline -- necessary in the sense that all areas of philosophy, all areas of science, and in fact any type of rational activity at all would be impossible without a metaphysical background or metaphysical presuppositions. Because of the extremely strong nature of this claim, it is not possible to put forward a very simple argument, although I will attempt to construct one. A crucial issue here is what (...) metaphysics in fact is -- the nature of metaphysics. The conception of metaphysics which I support could be called Aristotelian, as opposed to Kantian: metaphysics is the first philosophy and the basis of all other philosophical and scientific inquiry. I will argue that this is indeed the most plausible conception of metaphysics. (shrink)

I critically discuss Strawson's transcendental argument against other minds scepticism, and look at the prospects for a naturalised version of it.

J. Ladyman, Ladyman and Ross refine J. Worral's structural realism, by developing an ontic structural realism which they argue is a consistently naturalistic means of characterizing the ontology of fundamental physics. I argue that particular elements of M. Lange and M. Eklund strengthen and refine their project of characterizing fundamental physics via OSR and by extension, their presentation of information-theoretic structural realism. I demonstrate this point by situating M. Lange’s discussion of nomological modality and natural necessity within Ladyman and Ross’s (...) discussion of ITSR. The logical hierarchy evinced in Lange’s notion of ‘nomic stability’ further refines Ladyman and Ross’s claims through the addition of nuanced modal distinctions in a systematic framework. Moreover, I argue that what Lange considers are the ‘lawmakers’ serve as a de dicto rendition of some of Ladyman & Ross’s fundamental de re extensions and refinements of ‘real patterns’. (shrink)

The entailment connective is introduced by Priest (2006b). It aims to capture, in a dialetheically acceptable way, the informal notion of logical consequence. This connective does not “fall foul” of Curry’s Paradox by invalidating an inference rule called “Absorption” (or “Contraction”) and the classical logical theorem called “Assertion”. In this paper we show that the semantics of entailment, given by Priest in terms of possible worlds, is inadequate. In particular, we will argue that Priest’s counterexamples to Absorption and Assertion use (...) in the metalanguage a dialetheically unacceptable principle. Furthermore, we show that the rejection of Assertion undermines Priest’s claim that the entailment connective expresses the notion of logical consequence. (shrink)