Harman and Lewis credit Kripke with having formulated a puzzle that seems to show that knowledge entails dogmatism. The puzzle is widely regarded as having been solved. In this paper we argue that this standard solution, in its various versions, addresses only a limited aspect of the puzzle and holds no promise of fully resolving it. Analyzing this failure and the proper rendering of the puzzle, it is suggested that it poses a significant challenge for the defense of epistemic closure.

The idea that knowledge can be extended by inference from what is known seems highly plausible. Yet, as shown by familiar preface paradox and lottery-type cases, the possibility of aggregating uncertainty casts doubt on its tenability. We show that these considerations go much further than previously recognized and significantly restrict the kinds of closure ordinary theories of knowledge can endorse. Meeting the challenge of uncertainty aggregation requires either the restriction of knowledge-extending inferences to single premises, or eliminating epistemic uncertainty in (...) known premises. The first strategy, while effective, retains little of the original idea—conclusions even of modus ponens inferences from known premises are not always known. We then look at the second strategy, inspecting the most elaborate and promising attempt to secure the epistemic role of basic inferences, namely Timothy Williamson’s safety theory of knowledge. We argue that while it indeed has the merit of allowing basic inferences such as modus ponens to extend knowledge, Williamson’s theory faces formidable difficulties. These difficulties, moreover, arise from the very feature responsible for its virtue- the infallibilism of knowledge. (shrink)

Perception can’t have disjunctive content. Whereas you can think that a box is blue or red, you can’t see a box as being blue or red. Based on this fact, I develop a new problem for the ambitious predictive processing theory, on which the brain is a machine for minimizing prediction error, which approximately implements Bayesian inference. I describe a simple case of updating a disjunctive belief given perceptual experience of one of the disjuncts, in which Bayesian inference and predictive (...) coding pull in opposite directions, with the former implying that one’s confidence in the belief should increase, and the latter implying that it should decrease. Thus, predictive coding fails to approximately implement Bayesian inference across the interface between belief and perception. (shrink)

According to the thesis of transparency, subjects can attend only to the representational content of perceptual experience, never to the intrinsic properties of experience that carry this representational content, i.e., to “mental paint.” So far, arguments for and against transparency were conducted from the armchair, relying mainly on introspective observations. In this paper, we argue in favor of transparency, relying on the cognitive neuroscience of attention. We present a trilemma to those who hold that attention can be directed to mental (...) paint. Such attention is either first-order sensory, higher-order cognitive, or higher-order sensory attention. We argue that the notion of first-order sensory attention to mental paint is incompatible with the neuroscience of sensory attention; that higher-order cognitive attention to mental paint is irrelevant to transparency; and that the notion of higher-order sensory attention to mental paint has an apparently incoherent prediction. Via elimination, these considerations support the thesis of transparency. (shrink)

According to an influential philosophical view I call “the relational properties view”, “perspectival” properties, such as the elliptical appearance of a tilted coin, are relational properties of external objects. Philosophers have assessed this view on the basis of phenomenological, epistemological or other purely philosophical considerations. My aim in this paper is to examine whether it is possible to evaluate RPV empirically. In the first, negative part of the paper I consider and reject a certain tempting way of doing so. In (...) the second, positive part of the paper I suggest a novel way of evaluating RPV empirically, relying on the influential object files framework. (shrink)

The paper argues that knowledge is not closed under logical inference. The argument proceeds from the openness of evidential support and the dependence of empirical knowledge on evidence, to the conclusion that knowledge is open. Without attempting to provide a full-fledged theory of evidence, we show that on the modest assumption that evidence cannot support both a proposition and its negation, or, alternatively, that information that reduces the probability of a proposition cannot constitute evidence for its truth, the relation of (...) evidential support is not closed under known entailment. Therefore the evidence-for relation is deductively open regardless of whether evidence is probabilistic or not. Given even a weak dependence of empirical knowledge on evidence, we argue that empirical knowledge is also open. On this basis, we also respond to the strongest argument in support of knowledge closure. Finally, we present a number of significant benefits of our position, namely, offering a unified explanation for a range of epistemological puzzles. (shrink)

When viewing a circular coin rotated in depth, it fills an elliptical region of the distal scene. For some, this appears to generate a two-fold experience, in which one sees the coin as simultaneously circular (in light of its 3D shape) and elliptical (in light of its 2D ‘perspectival shape’ or ‘p-shape’). An energetic philosophical debate asks whether the latter p-shapes are genuinely presented in perceptual experience (as ‘perspectivalists’ argue) or if, instead, this appearance is somehow derived or inferred from (...) experience (as ‘anti-perspectivalists’ argue). This debate, however, has largely turned on introspection. In a recent study, Morales, Bax, and Firestone (2020) aim to provide the first empirical test of this question. They asked subjects to find an elliptical coin seen face-on from a search array that also included a circular coin seen either face-on or at an angle. They found that subjects reacted more slowly when the distracting circle was seen at an angle, such that it’s p-shape matched that of the target ellipse. From this, they concluded that the similar p-shape between the ellipse and circle constituted a phenomenal similarity between the two, and thus that perspectivalism is true. We show that these results can also be explained by pre-attentive guidance by unconscious representations (in what follows, just “unconscious pre-attentive guidance”) and that this explanation is at least as plausible as one from phenomenal similarity. Thus, we conclude that the experiment does not support perspectivalism over anti-perspectivalism. (shrink)

Timothy Williamson has famously argued that the principle should be rejected. We analyze Williamson's argument and show that its key premise is ambiguous, and that when it is properly stated this premise no longer supports the argument against. After canvassing possible objections to our argument, we reflect upon some conclusions that suggest significant epistemological ramifications pertaining to the acquisition of knowledge from prior knowledge by deduction.

There are few indulgences academics can crave more than to have their work considered and addressed by leading researchers in their field. We have been fortunate to have two outstanding philosophers from whose work we have learned a great deal give ours their thoughtful attention. Grappling with Stephen Yablo’s, and Juan Comesaña’s comments and criticisms has helped us gain a better understanding of our ideas as well as their shortcomings. We are extremely grateful to them for the attentiveness and seriousness (...) with which they have considered our arguments and to philosophical studies for giving us this opportunity. Given the substantive difference between the two response papers, there is not much beyond sincere gratitude that we can covey to them jointly. We will therefore address them in turn. (shrink)

According to the influential thesis of attentional transparency, in having or reflecting on an ordinary visual experience, we can attend only outwards, to qualities the experience represents, never to intrinsic qualities of the experience itself, i.e., to “mental paint.” According to the competing view, attentional semitransparency, although we usually attend outwards, to qualities the experience represents, we can also attend inwards, to mental paint. So far, philosophers have debated this topic in strictly armchair means, especially phenomenological reflection. My aim in (...) this paper is to show how to design an experiment, using the change detection paradigm for studying visual working memory that, if yielding positive results, would support AS. The structure of the argument is as follows. In standard change detection tasks, which involve attention to qualities the experience represents, there exists a known object integration effect (Luck and Vogel in Nature 390(6657):279–281, 1997). I formulate a hypothesis I call “the turn-off hypothesis,” according to which this effect does not exist in change detection tasks where subjects are instructed to attend to mental paint. I argue that, given AS, we have some reason to expect the turn-off hypothesis to be true, but given AT, we do not. Consequently, the truth of the turn-off hypothesis would support AS. I further argue that one can straightforwardly test the turn-off hypothesis, taking the standard change detection paradigm and instructing participants to attend inwards. (shrink)

A commonly-discussed feature of perceptual experience is that it has ‘assertoric’ or ‘phenomenal’ force. We will start by discussing various descriptions of the assertoricity of perceptual experience. We will then adopt a minimal characterization of assertoricity: a perceptual experience has assertoric force just in case it inclines the perceiver to believe its content. Adducing cases that show that visual experience is not always assertoric, we will argue that what renders these visual experiences non-assertoric is that they are penetrated by belief-like (...) imaginings. Lastly, we will explain why it is that when belief-like imaginings—as opposed to beliefs (and other cognitive states)—penetrate visual experience, they render visual experiences non-assertoric. (shrink)

When characterizing the content of a subject’s perceptual experience, does their seeing an object entail that their visual experience represents it as being a certain way? If it does, are they thereby in a position to have perceptually-based thoughts about it? On one hand, representationalists are under pressure to answer these questions in the affirmative. On the other hand, it seems they cannot. This paper presents a puzzle to illustrate this tension within orthodox representationalism. We identify several interesting morals which (...) may be drawn in response, each of which teaches us something interesting and important about perceptual experience and its interface with cognition and related phenomena. (shrink)

This paper proposes a novel experimental approach that would help to determine whether perspectival shapes, such as the elliptical profile of a tilted plate or coin, are part of perceptual experience. If they are part of perceptual experience, then it should be possible to identify these shapes simply by attending appropriately to them. Otherwise, in order to identify perspectival shapes they must first be constructed in the visual imagination. We propose that these accounts of perspectival identification can be tested by (...) measuring the interference between visual and verbal working memory load, respectively, and the identification of perspectival shapes in the appearance of a 3D object. (shrink)

According to capacitism, to perceive is to employ personal-level, perceptual capacities. In a series of publications, Schellenberg (2016, 2018, 2019b, 2020) has argued that capacitism offers unified analyses of perceptual particularity, perceptual content, perceptual consciousness, perceptual evidence, and perceptual knowledge. “Capacities first” (2020: 715); appealing accounts of an impressive array of perceptual and epistemological phenomena will follow. We argue that, given the Schellenbergian way of individuating perceptual capacities which underpins the above analyses, perceiving an object does not require employing a (...) perceptual capacity which picks it out. Although each eye, used on its own, can suffice for perceiving objects in one’s environment, binocular vision allows one to see the same object(s) via both eyes, taking advantage of informational disparities registered by each eye. Yet in certain conditions it is possible to simultaneously see one object via the left eye and a distinct object via the right eye (at least when the inputs are sufficiently similar to prevent the onset of binocular rivalry). We argue that capacitism has trouble making sense of this. After surveying responses, we conclude that not all of the above phenomena can be unified under the capacitist framework. We then present a more nuanced, disjunctivist account of how capacities are individuated. While it may be illuminating to think of perceiving as the employment of perceptual capacities, this picture does not best favour a ‘common factor’ theory of perceptual content in the way existing presentations have envisaged. (shrink)