Modal Epistemology

In "What is it Like to be a Bat?" Thomas Nagel argues that we cannot imagine what it is like to be a bat or presently understand how physicalism might be true. Both arguments have been seriously misunderstood. I defend them against various objections, point out a problem with the argument against physicalism, and show how the problem can be solved.

In his 1998 postscript to ‘The Possibility of Resurrection’ Peter van Inwagen argues that the scenario he describes by which God might resurrect a human organism, even though probably not true, is still conceivable and, consequently, ‘serves to establish a possibility’, namely, the metaphysical possibility of the resurrection of material beings. Van Inwagen, however, has also argued in favour of ‘modal scepticism’ [van Inwagen in, God, knowledge and mystery: essays in philosophical theology, Cornell University Press, Ithaca 1995b, pp. 11–12; van (...) Inwagen in, Philos Stud 92:67–84, 1998a]. That is, he thinks that we should limit all our claims about what is possible to ‘ordinary propositions about everyday matters’, 1998a). In this paper I argue that van Inwagen’s modal argument as found in ‘The Possibility of Resurrection’ is inconsistent with his modal scepticism as found in ‘Modal Epistemology’. In consequence, I argue that, given his modal scepticism, the task van Inwagen set himself in ‘The Possibility of Resurrection’ has not been achieved. (shrink)

It is widely suspected that arguments from conceivability, at least in some of their more notorious instances, are unsound. However, the reasons for the failure of conceivability arguments are less well agreed upon, and it remains unclear how to distinguish between sound and unsound instances of the form. In this paper I provide an analysis of the form of arguments from conceivability, and use this analysis to diagnose a systematic weakness in the argument form which reveals all its instances to (...) be, roughly, either uninformative or unsound. I illustrate this conclusion through a consideration of David Chalmers. (shrink)

Hill and Levine offer alternative explanations of these conceivabilities, concluding that these conceivabilities are thereby defeated as evidence. However, this strategy fails because their explanations generalize to all conceivability judgments concerning phenomenal states. Consequently, one could defend absolutely any theory of phenomenal states against conceivability arguments in just this way. This result conflicts with too many of our common sense beliefs about the evidential value of conceivability with respect to phenomenal states. The general moral is that the application of such (...) principles of explanatory defeat is neither simple nor straightforward. (shrink)

Christopher Hill and Joseph Levine have argued that the conceivabilities involved in anti-materialist arguments are defeated as evidence of possibility. Their strategy assumes the following principle: the conceivability of a state of affairs S constitutes evidence for the possibility of S only if the possibility of S is the best explanation of the conceivability of S. So if there is a better explanation of the conceivability of S than its possibility, then the conceivability of S is thereby defeated as evidence (...) of possibility. Hill and Levine proceed to offer alternative explanations of these conceivabilities, concluding that these conceivabilities are thereby defeated as evidence. However, this strategy fails because their explanations generalize to all conceivability judgments concerning phenomenal states. Consequently, one could defend absolutely any theory of phenomenal states against conceivability arguments in just this way. This result conflicts with too many of our common sense beliefs about the evidential value of conceivability with respect to phenomenal states. The general moral is that the application of such principles of explanatory defeat is neither simple nor straightforward. (shrink)

The classical view of the relationship between necessity and apriority, defended by Leibniz and Kant, is that all necessary truths are known a priori. The classical view is now almost universally rejected, ever since Saul Kripke and Hilary Putnam discovered that there are necessary truths that are known only a posteriori. However, in recent years a new debate has emerged over the epistemology of these necessary a posteriori truths. According to one view – call it the neo-classical view – knowledge (...) of a necessary truth always depends on at least one item of a priori knowledge. According to the rival view – call it the neoempiricist view – our knowledge of necessity is sometimes broadly empirical. In this paper I present and defend an argument against the neo-empiricist view. I argue that knowledge of the necessity of a necessary truth could not be broadly empirical. (shrink)

Contingentism, generally contrasted with law necessitarianism, is the view that the laws of nature are contingent. It is often coupled with the claim that their contingency is knowable a priori. This paper considers Bird's (2001, 2002, 2005, 2007) arguments for the thesis that, necessarily, salt dissolves in water; and it defends his view against Beebee's (2001) and Psillos's (2002) contingentist objections. A new contingentist objection is offered and several reasons for scepticism about its success are raised. It is concluded that (...) certain higher-level laws describing the behaviours of molecular compounds may be necessary due to their dependence on underlying physical laws, and that the modal status of laws of nature cannot be determined a priori, as the structural features of the substances and properties they govern must first be investigated. (shrink)

I want to model a finite, fallible cognitive agent who imagines that p in the sense of mentally representing a scenario—a configuration of objects and properties—correctly described by p. I propose to capture imagination, so understood, via variably strict world quantifiers, in a modal framework including both possible and so-called impossible worlds. The latter secure lack of classical logical closure for the relevant mental states, while the variability of strictness captures how the agent imports information from actuality in the imagined (...) non-actual scenarios. Imagination turns out to be highly hyperintensional, but not logically anarchic. Section 1 sets the stage and impossible worlds are quickly introduced in Sect. 2. Section 3 proposes to model imagination via variably strict world quantifiers. Section 4 introduces the formal semantics. Section 5 argues that imagination has a minimal mereological structure validating some logical inferences. Section 6 deals with how imagination under-determines the represented contents. Section 7 proposes additional constraints on the semantics, validating further inferences. Section 8 describes some welcome invalidities. Section 9 examines the effects of importing false beliefs into the imagined scenarios. Finally, Sect. 10 hints at possible developments of the theory in the direction of two-dimensional semantics. (shrink)

I present an approach to our conceiving absolute impossibilities—things which obtain at no possible world—in terms of ceteris paribus intentional operators: variably restricted quantifiers on possible and impossible worlds based on world similarity. The explicit content of a representation plays a role similar in some respects to the one of a ceteris paribus conditional antecedent. I discuss how such operators invalidate logical closure for conceivability, and how similarity works when impossible worlds are around. Unlike what happens with ceteris paribus counterfactual (...) conditionals, the closest worlds are relevantly closest belief-worlds: closest to how things are believed to be, rather than to how they are. Also, closeness takes into account apriority and the opacity of intentional contexts. (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)

This paper argues: (1) All knowledge from fiction is from imagination (2) All knowledge from imagination is modal knowledge (3) So, all knowledge from fiction is modal knowledge Moreover, some knowledge is from fiction, so (1)-(3) are non-vacuously true.

The central recommendation of this article is that philosophers trained in the analytic tradition ought to add the sensibilities and skills of the historian to their methodological toolkit. The value of an historical approach to strictly philosophical matters is illustrated by a case study focussing on the medieval origin of conceivability arguments and contemporary views of modality. It is shown that common metaphilosophical views about the nature of the philosophical enterprise as well as certain inference patterns found in thinkers from (...) Descartes to Chalmers have their origin in the theological concerns of the Scholastics. Since these assumptions and inference patterns are difficult to motivate when shorn of their original theological context, the upshot is that much post-Cartesian philosophy is cast in an altogether unfamiliar, and probably unwelcome, light. The methodological point, however, is that this philosophical gain is born of acquaintance with the history of ideas. (shrink)

Focusing on Meister Eckhart, John Duns Scotus, Hervaeus Natalis, Durandus of St.-PourAain, Walter Burley and Petrus Aureoli, this volume investigates the nature ...

In The Conscious Mind, D. Chalmers appeals to his semantic framework in order to show that conceivability, as employed in his "zombie" argument for dualism , is sufficient for genuine possibility. I criticize this attempt.

A leading scholar in the psychology of thinking and reasoning argues that the counterfactual imagination—the creation of "if only" alternatives to ...

forthcoming in a collection of papers (from OUP, edited by Bob Hale) given at the Arché modality conference, St Andrews University, 7th-9th June 2006.

Famous examples of conceivability arguments include (i) Descartes’ argument for mind-body dualism, (ii) Kripke's ‘modal argument’ against psychophysical identity theory, (iii) Chalmers’ ‘zombie argument’ against materialism, and (iv) modal versions of the ontological argument for theism. In this paper, we show that for any such conceivability argument, C, there is a corresponding ‘mirror argument’, M. M is deductively valid and has a conclusion that contradicts C's conclusion. Hence, a proponent of C—henceforth, a ‘conceivabilist’—can be warranted in holding that C's premises (...) are conjointly true only if she can find fault with one of M's premises. But M's premises are modelled on a pair of C's premises. The same reasoning that supports the latter supports the former. For this reason, a conceivabilist can repudiate M's premises only on pain of severely undermining C's premises. We conclude on this basis that all conceivability arguments, including each of (i)–(iv), are fallacious. (shrink)

This paper concerns the three great modal dichotomies: (i) the necessary/contingent dichotomy; (ii) the a priori/empirical dichotomy; and (iii) the analytic/synthetic dichotomy. These can be combined to produce a tri-dichotomy of eight modal categories. The question as to which of the eight categories house statements and which do not is a pivotal battleground in the history of analytic philosophy, with key protagonists including Descartes, Hume, Kant, Kripke, Putnam and Kaplan. All parties to the debate have accepted that some categories are (...) void. This paper defends the contrary view that all eight categories house statements—a position I dub ‘octopropositionalism’. Examples of statements belonging to all eight categories are given. (shrink)

Kripke claims that there are necessary a posteriori truths and contingent a priori truths. These claims challenge the traditional Kantian view that (K) All knowledge of necessary truths is a priori and all a priori knowledge is of necessary truths. Kripke’s claims continue to be resisted, which indicates that the Kantian view remains attractive. My goal is to identify the most plausible principles linking the epistemic and the modal. My strategy for identifying the principles is to investigate two related questions. (...) Are there compelling general supporting arguments for (K)? Are there decisive counterexamples to (K)? My investigation uncovers two intuitively plausible principles that are not open to decisive counterexamples but which enjoy no compelling independent support. (shrink)

The purpose of this article is to defend Hume's claim that whatever is conceivable is possible from a criticism by William Kneale. Kneale argues that although a mathematician can conceive of the falsehood of the Goldbach conjecture, he does not conclude that it is not necessarily true. The author suggests that by taking into account Hume's distinction between intuitive and demonstrative knowledge, a revised version of his claim can be offered which is not open to Kneale's criticism.

What follows are compressed versions of three lectures on the subject of "Mind and Modality", given at Princeton University the week of October 12-16, 1998. The first two form a series; the third stands alone to some extent. All are philosophically technical, and probably of interest mainly to philosophers. I hope that they make sense, at least to those familiar with my book _The Conscious Mind_ . Lecture 1 recapitulates some of the material in the book in a somewhat different (...) form, and adds some further material on conditionals and on Kripke. Note that section has a more or less definitive formalization of the anti-materialist argument from the book . Lecture 2 pushes deeper into the heart of modality, further investigating the conceivability/possibility relationship and the epistemology of modality , and arguing for a sort of modal rationalism. Lecture 3 gives an analysis of the content of beliefs about experiences, and applies this to a number of epistemological issues, including incorrigibility and the dialectic on "The Myth of the Given". (shrink)

John Perry's book Knowledge, Possibility, and Consciousness is a lucid and engaging defense of a physicalist view of consciousness against various anti-physicalist arguments. In what follows, I will address Perry's responses to the three main anti-physicalist arguments he discusses: the zombie argument , the knowledge argument , and the modal argument.

There is a long tradition in philosophy of using a priori methods to draw conclusions about what is possible and what is necessary, and often in turn to draw conclusions about matters of substantive metaphysics. Arguments like this typically have three steps: first an epistemic claim , from there to a modal claim , and from there to a metaphysical claim.

The book is an extended study of the problem of consciousness. After setting up the problem, I argue that reductive explanation of consciousness is impossible , and that if one takes consciousness seriously, one has to go beyond a strict materialist framework. In the second half of the book, I move toward a positive theory of consciousness with fundamental laws linking the physical and the experiential in a systematic way. Finally, I use the ideas and arguments developed earlier to defend (...) a form of strong artificial intelligence and to analyze some problems in the foundations of quantum mechanics. (shrink)

Analytic epistemology is traditionally interested in rational reconstructions of cognitive pro- cesses. The purpose of these rational reconstructions is to make plain how a certain cognitive process might eventually result in knowledge or justi?ed beliefs, etc., if we pre-theoretically think that we have such knowledge or such justi?ed beliefs. Typically a rational reconstruction assumes some unproblematic basis of knowledge and some justi?cation-preserving inference pattern and then goes on to show how these two su ce to generate the explicandum.

In addition to conceiving of such imaginary scenarios as those involving philosophical zombies, we may conceive of such things being conceived. Call these higher order conceptions ‘meta-conceptions’. Sorensen (2006) holds that one can entertain a meta-conception without thereby conceiving of the embedded lower-order conception. So it seems that I can meta-conceive possibilities which I cannot conceive. If this is correct, then meta-conceptions provide a counter-example to the claim that possibility entails conceivability. Moreover, some of Sorensen’s discussion suggests the following argument: (...) if the conceivability of some proposition entails its possibility, then the meta-conceivability of some proposition entails its possibility; but we can meta-conceive impossibilities; so conceivability doesn’t entail possibility. In this paper, I’ll argue that one cannot entertain a meta-conception without thereby conceiving of the embedded lower-order conception. And so we can neither meta-conceive impossibilities nor meta-conceive possibilities of which we cannot thereby conceive. (shrink)

Inspired by Niiniluoto’s account of the logic of imagination, this work proposes a combined logic able to deal with interactions of imagination, conception and possibility. It combines Descartes’ view according to which imagination implies conception with Hume’s view according to which both imagination and conception imply possibility.

A topological model of elementary semiotic schemes is presented. Implications are discussed with respect to the establishment of abstract terms and the search for ultimate meaning.

The method of thought experiments or possible cases is widespread in philosophy and elsewhere. Thought experiments come with variegated theoretical commitments. These commitments are risky. They may turn out to be false or at least controversial. Other things being equal, it seems preferable to do with minimal commitments. I explore exemplary ways of minimising commitments, focusing on modal ones. There is a near-consensus to treat the scenarios considered in thought experiments as metaphysical possibilities. I challenge this consensus. Paradigmatic thought experiments (...) do not have to come with a commitment to metaphysical possibilities. In the first section, I point out difficulties with the prevailing focus on metaphysical possibilities. In the second section, I present alternative formalisations of a paradigmatic thought experiment, the Gettier experiment. Gettier’s words leave open the kind of possibilities under consideration. The standard way of spelling out Gettier’s argument uses metaphysical possibilities. One alternative proposal uses nomological possibilities. A second one uses epistemic possibilities. My modest conclusion: as long as it is not established that a thought experiment requires a commitment to metaphysical modality, one should avoid such a commitment. My preferred way of doing so is to replace the commitment to one particular formalisation by a commitment to a disjunction of alternative formalisations. (shrink)

Many philosophers are very sanguine about the cognitive contributions of fiction to science and philosophy. I focus on a case study: Ichikawa and Jarvis’s account of thought experiments in terms of everyday fictional stories. As far as the contribution of fiction is not sui generis, processing fiction often will be parasitic on cognitive capacities which may replace it; as far as it is sui generis, nothing guarantees that fiction is sufficiently well-behaved to abide by the constraints of scientific and philosophical (...) discourse, not even by the minimum requirements of conceptual and logical coherence. (shrink)

I outline Hume’s views about conceivability evidence. Then I critically scrutinize two threats to conceivability-based modal epistemology. Both arise from Hume’s criticism of claims to knowing necessary causal relationships: Firstly, a sceptical stance towards causal necessity may carry over to necessity claims in general. Secondly, since – according to a sceptical realist reading – Hume grants the eventuality of causal powers grounded in essential features of objects, conceivability-based claims to comprehensive metaphysical possibilities seem endangered. I argue that although normal conceivability-based (...) claims are defeasible, they are prima facie vindicated. (shrink)

In this article, I defend the view that we can acquire factual knowledge – that is, contingent propositional knowledge about certain (perceivable) aspects of reality – on the basis of imaginative experience. More specifically, I argue that, under suitable circumstances, imaginative experiences can rationally determine the propositional content of knowledge-constituting beliefs – though not their attitude of belief – in roughly the same way as perceptual experiences do in the case of perceptual knowledge. I also highlight some philosophical consequences of (...) this conclusion, especially for the issue of whether imagination can help us to learn something from fictions. (shrink)

This chapter overviews Hume’s thoughts on the nature and role of imagining and focusses primarily on three important distinctions that Hume draws among our conscious mental episodes: (i) between impressions and ideas; (ii) between ideas of the memory and ideas of the imagination; and (iii), among the ideas of the imagination, between ideas of the judgement and ideas of the fancy. In addition, the chapter considers Hume’s views on the imagination as a faculty of producing ideas, as well as on (...) the part that imagining plays in the acquisition of modal knowledge and in the comprehension of, and resistance to, false or fictional opinions. (shrink)

This is the original, longer draft for my entry on Hume in the 'The Routledge Hand- book of Philosophy of Imagination', edited by Amy Kind and published by Routledge in 2016 (see the separate entry). — Please always cite the Routledge version, unless there are passages concerned that did not make it into the Handbook for reasons of length. — -/- This chapter overviews Hume’s thoughts on the nature and the role of imagining, with an almost exclusive focus on the (...) first book of his Treatise of Human Nature. Over the course of this text, Hume draws and discusses three important distinctions among our conscious mental episodes (or what he calls ‘perceptions’): (i) between impressions (including perceptual experiences) and ideas (including recollections, imaginings and occurrent beliefs); (ii) between ideas of the memory and ideas of the imagination; and (iii), among the ideas of the imagination, between ideas of the judgement (i.e. occurrent beliefs) and ideas of the fancy (i.e. imaginings). I discuss each distinction in turn, also in connection to contemporary views on imagining. In addition, I briefly consider Hume’s views on the imagination as a faculty aimed at the production of ideas, as well as on the role that imagining plays in the wider context of our mental lives, notably in the acquisition of modal knowledge and in the comprehension of, and resistance to, stories and opinions that we take to be false or fictional. (shrink)

In the introduction to the Critique of Pure Reason (2nd edition), Kant claims that a transcendental cognition is a one ‘that is occupied not so much with objects but rather with our mode of cognition of objects insofar as is this ought to be possible a priori (a priori möglich sein soll)’. In this paper, I argue that Kant scholarship should take into account the specific signification of the term ‘sollen’, which might require us to reconsider the usual distinction between (...) the system of freedom and the system of nature. Following a Fichtean perspective, I will try to show that, even if ‘sollen’ in this context does not refer to a duty in the strict sense, it does refer to the demand that transcendental philosophy itself be possible. I will argue that this demand is contingent at its very origin and, accordingly, expresses a particular kind of ‘freedom’. On this basis I will consider the tribunal of reason enacted in the Critique of Pure Reason as a tribunal that emerges from a free decision, in which the transcendental philosopher imagines its own possibility. Because it is a ‘free’ and ‘contingent’ tribunal, it cannot exceed the status of a problematic philosophical strategy. (shrink)

Radical skepticism relies on the hypothesis that one could be completely cut off from the external world. In this paper, I argue that this hypothesis can be rationally motivated by means of a conceivability argument. Subsequently, I submit that this conceivability argument does not furnish a good reason to believe that one could be completely cut off from the external world. To this end, I show that we cannot adequately conceive scenarios that verify the radical skeptical hypothesis. Attempts to do (...) so fall prey to one or another of three pitfalls: they end up incomplete, reveal a deep contradiction or recreate a non-skeptical hypothesis. I use these results to improve upon Pritchard’s recent attempt at undercutting radical skepticism. (shrink)

This is a sequel to our dialogue "Che cosa c'è e che cos'è (2003), focusing on the interplay between what there is and what there could be—between actuality and possibility—from the perspective of Hylas (here: the realist philosopher) and from the perspective of Philonous (here: the conventionalist anti-realist).