Animate vision systems have gaze control mechanisms that can actively position the camera coordinate system in response to physical stimuli. Compared to passive systems, animate systems show that visual computation can be vastly less expensive when considered in the larger context of behavior. The most important visual behavior is the ability to control the direction of gaze. This allows the use of very low resolution imaging that has a high virtual resolution. Using such a system in a controlled way (...) provides additional constraints that dramatically simplify the computations of early vision. Another important behavior is the way the environment “behaves‘. Animate systems under real-time constraints can further reduce their computational burden by using environmental cues that are perspicuous in the local context. A third source of economy is introduced when behaviors are learned. Because errors are rarely fatal, systems using learning algorithms can amortize computational cost over extended periods. Further economies can be achieved when the learning system uses indexical reference, which is a form of dynamic variable binding. Animate vision is a natural way of implementing this dynamic binding. (shrink)

Although the study of visual perception has made more progress in the past 40 years than any other area of cognitive science, there remain major disagreements as to how closely vision is tied to general cognition. This paper sets out some of the arguments for both sides and defends the position that an important part of visual perception, which may be called early vision or just vision, is prohibited from accessing relevant expectations, knowledge and utilities - in (...) other words it is cognitively impenetrable. That part of vision is complex and articulated and provides a representation of the 3-D surfaces of objects sufficient to serve as an index into memory, with somewhat different outputs being made available to other systems such as those dealing with motor control. The paper also addresses certain conceptual and methodological issues, including the use of signal detection theory and event-related potentials to assess cognitive penetration of vision. A distinction is made among several stages in visual processing. These include, in addition to the inflexible early-vision stage, a pre-perceptual attention allocation stage and a post-perceptual evaluation, memory-accessing, and inference stage which provide several different highly constrained ways in which cognition can affect the outcome of visual perception. The paper discusses arguments that have been presented in both computer vision and psychology showing that vision is "intelligent" and involves elements of problem solving". It is suggested that these cases do not show cognitive penetration, but rather they show that certain natural constraints on interpretation, concerned primarily with optical and geometrical properties of the world, have been compiled into the visual system. The paper also examines a number of examples where instructions and "hints" are alleged to affect. (shrink)

It is natural to assume that the fine-grained and highly accurate spatial information present in visual experience is often used to guide our bodily actions. Yet this assumption has been challenged by proponents of the Two Visual Systems Hypothesis , according to which visuomotor programming is the responsibility of a “zombie” processing stream whose sources of bottom-up spatial information are entirely non-conscious . In many formulations of TVSH, the role of conscious vision in action is limited to “recognizing objects, (...) selecting targets for action, and determining what kinds of action, broadly speaking, to perform” . Our aim in this study is to show that the available evidence not only fails to support this dichotomous view but actually reveals a significant role for conscious vision in motor programming, especially for actions that require deliberate attention. (shrink)

Colour vision plays a foundational explanatory role in the philosophy of colour, and serves as perennial quarry in the wider philosophy of perception. I present two contributions to our understanding of this notion. The first is to develop a constitutive approach to characterizing colour vision. This approach seeks to comprehend the nature of colour vision qua psychological kind, as contrasted with traditional experiential approaches, which prioritize descriptions of our ordinary visual experience of colour. The second contribution is (...) to argue that colour vision does not constitutively involve the ability to see colours, in a natural and categorically committed sense. I argue that two subjects exactly alike in respect of their constitutive colour vision abilities could differ in respect of whether or not they have categorical perception of colour. The argument is supported by thought experiment and dissociations observed in cognitive neuropsychology. The argument also bears connections to recent neo-Whorfian accounts of colour categorization. _1._ Introduction _2._ Colour Vision, Experience, and Natures _3._ The Central Argument _3.1._ Colour constancy and discrimination _3.2._ Dissociating colour vision and categorical perception for colour _4._ Whorf and the View from Cognitive Neuropsychology _5._ Conclusion. (shrink)

This textbook on vision reflects the integrated computational approach of modern research scientists, combining psychological, computational and neuroscientific perspectives.

In this paper, I critically assess the enactive account of visual perception recently defended by Alva Noë (2004). I argue inter alia that the enactive account falsely identifies an object’s apparent shape with its 2D perspectival shape; that it mistakenly assimilates visual shape perception and volumetric object recognition; and that it seriously misrepresents the constitutive role of bodily action in visual awareness. I argue further that noticing an object’s perspectival shape involves a hybrid experience combining both perceptual and imaginative elements—an (...) act of what I call ‘make‐perceive’. (shrink)

David Milner and Melvyn Goodale’s dissociation hypothesis is commonly taken to state that there are two functionally specialized cortical streams of visual processing originating in striate (V1) cortex: a dorsal, action-related “unconscious” stream and a ventral, perception-related “conscious” stream. As Milner and Goodale acknowledge, findings from blindsight studies suggest a more sophisticated picture that replaces the distinction between unconscious vision for action and conscious vision for perception with a tripartite division between unconscious vision for action, conscious (...) class='Hi'>vision for perception, and unconscious vision for perception. The combination excluded by the tripartite division is the possibility of conscious vision for action. But are there good grounds for concluding that there is no conscious vision for action? There is now overwhelming evidence that illusions and perceived size can have a significant effect on action (Bruno & Franz, 2009; Dassonville & Bala, 2004; Franz & Gegenfurtner, 2008; McIntosh & Lashley, 2008). There is also suggestive evidence that any sophisticated visual behavior requires collaboration between the two visual streams at every stage of the process (Schenk & McIntosh, 2010). I nonetheless want to make a case for the tripartite division between unconscious vision for action, conscious vision for perception, and unconscious vision for perception. My aim here is not to refute the evidence showing that conscious vision can affect action but rather to argue (a) that we cannot gain cognitive access to action-guiding dorsal stream representations, and (b) that these representations do not correlate with phenomenal consciousness. This vindicates the semi-conservative view that the dissociation hypothesis is best understood as a tripartite division. (shrink)

According to Milner and Goodale’s dual visual systems (DVS) theory, a division obtains between visual consciousness and motor action, in that the visual system producing conscious vision (the ventral stream) is distinct from the one guiding action (the dorsal stream). That there would be this division is often taken (by Andy Clark and others) to undermine the folk view on how consciousness and action relate. However, even if this division obtains, this leaves open the possibility that con- scious ventral (...) information is often transmitted to the uncon- scious dorsal stream and then used to guide action, a possibility seeming to preserve a significant role for consciousness in action. This article assesses this possibility. In course of doing so, we will review those arguments recently having been made against the DVS view on how visual consciousness and action relate (ones due to, e.g., Briscoe and Schwenkler, or Schenk and McIntosh). What we will find is that, if we properly analyze the data upon which these arguments are based, we are still left with the impression that the DVS view is largely correct; i.e., it is only rarely that visual experience guides action. (shrink)

Colour fascinates all of us, and scientists and philosophers have sought to understand the true nature of colour vision for many years. In recent times, investigations into colour vision have been one of the main success stories of cognitive science, for each discipline within the field - neuroscience, psychology, linguistics, computer science and artificial intelligence, and philosophy - has contributed significantly to our understanding of colour. Evan Thompson's book is a major contribution to this interdisciplinary project. Colour (...) class='Hi'>Vision provides an accessible review of the current scientific and philosophical discussions of colour vision. Thompson steers a course between the subjective and objective positions on colour, arguing for a relational account. This account develops a novel `ecological' approach to colour vision in cognitive science and the philosophy of perception. It is vital reading for all cognitive scientists and philosophers whose interests touch upon this central area. (shrink)

Vision and the gaze are key issues in the analysis of racism, sexism and ethnocentrism. In recent radical theory, generally, and French theory in particular, vision has been seen as a means of control. But this view is often unnuanced. It bypasses questions such as: Why is it that contemporary theories have been so critical of vision, and generous towards listening (in psychoanalysis) and language (in philosophy)? This collection of original essays brings together historical studies and contemporary (...) theoretical perspectives on vision. The historical papers focus in turn on Ancient Greece, medieval theology, the Renaissance, the Enlightenment and the nineteenth century. These historical studies are themselves thoroughly informed by poststructuralist theory. They provide a rigorous background for several new, exciting articles on vision and its bearings for feminism, race, sexual orientation, film and art. This collection is the first of its kind in juxtaposing historical and contemporary. (shrink)

The first of three volumes of essays by Quentin Skinner, one of the world's leading intellectual historians. This collection includes some of his most important philosophical and methodological statements written over the past four decades, each carefully revised for publication in this form. In a series of seminal essays Professor Skinner sets forth the intellectual principles that inform his work. Writing as a practising historian, he considers the theoretical difficulties inherent in the pursuit of knowledge and interpretation, and elucidates the (...) methodology which finds its expression in his two successive volumes. All of Professor Skinner's work is characterised by philosophical power, limpid clarity, and elegance of exposition; these essays, many of which are now recognised classics, provide a fascinating and convenient digest of the development of his thought. (shrink)

The general problem of visual search can be shown to be computationally intractable in a formal, complexity-theoretic sense, yet visual search is extensively involved in everyday perception, and biological systems manage to perform it remarkably well. Complexity level analysis may resolve this contradiction. Visual search can be reshaped into tractability through approximations and by optimizing the resources devoted to visual processing. Architectural constraints can be derived using the minimum cost principle to rule out a large class of potential solutions. The (...) evidence speaks strongly against bottom-up approaches to vision. In particular, the constraints suggest an attentional mechanism that exploits knowledge of the specific problem being solved. This analysis of visual search performance in terms of attentional influences on visual information processing and complexity satisfaction allows a large body of neurophysiological and psychological evidence to be tied together. (shrink)

This paper examines Milner and Goodale’s hypothesis about the two visual streams and raises the questions of whether properties in egocentric space (commonly associated with the vision-for-action, or "dorsal," stream) can be part of the phenomenal content of perceptual experience, or only properties in allocentric space (commonly associated with the vision-for-perception, or "ventral," stream) can play this role, and how (if at all) properties in egocentric space differ from properties in allocentric space. These questions are reminiscent of issues (...) raised by Christopher Peacocke's "equal-sized trees" case: if you are looking at equal-sized trees on the side of a road, the trees will phenomenally look to you to be equally tall. But it is also true that a tree will take up more of the space in your visual field the closer it is to you. So, the equal-sized trees will also phenomenally look to you to have different heights. Your (visual) perceptual experience is not illusory. That is, the trees veridically look to you to have the same height, and they also veridically look to you to have different heights. Call the sort of issue raised here the "problem of dual looks." I provide a solution to the problem of dual looks that helps shed light on whether properties in egocentric space can be part of the phenomenal content of perceptual experience, and how (if at all) properties in egocentric space differ from properties in allocentric space. (shrink)

This book analyzes contemporary visual art produced in the context of conflict and trauma from a range of countries, including Colombia, Northern Ireland, South Africa, and Australia. It focuses on what makes visual language unique, arguing that the "affective" quality of art contributes to a new understanding of the experience of trauma and loss. By extending the concept of empathy, it also demonstrates how we might, through art, make connections with people in different parts of the world whose experiences differ (...) from our own. The book makes a distinct contribution to trauma studies, which has tended to concentrate on literary forms of expression. It also offers a sophisticated theoretical analysis of the operations of art, drawing on philosophers such as Gilles Deleuze, but setting this within a postcolonial framework. _Empathic Vision_ will appeal to anyone interested in the role of culture in post-September 11 global politics. (shrink)

Empirical work and philosophical analysis have led to widespread acceptance that vision for action, served by the cortical dorsal stream, is unconscious. I argue that the empirical argument for this claim is unsound. That argument relies on subjects’ introspective reports. Yet on biological grounds, in light of the theory of primate cortical vision, introspection has no access to dorsal stream mediated visual states. It is thus wrongly assumed that introspective reports speak to absent phenomenology in the dorsal stream. (...) In light of this, I consider a different conception of consciousness’s relation to agency in terms of access. While theoretical reasons suggest that the inaccessibility of the dorsal stream to conceptual report is evidence that it is unconscious, this position begs important questions. I propose a broader notion of access in respect of the guidance of intentional agency and not, narrowly, conceptual report (Note: this paper contradicts my earlier paper, "The Case for Zombie Agency"). (shrink)

This book is a major contribution to the interdisciplinary project of investigating the true nature of color vision.

This book introduces the reader to ethics by examining a current and important debate. During the last fifty years the orthodox position in ethics has been a broadly non-cognitivist one: since there are no moral facts, moral remarks are best understood, not as attempting to describe the world, but as having some other function - such as expressing the attitudes or preferences of the speaker. In recent years this position has been increasingly challenged by moral realists who maintain that there (...) are moral facts; there is a truth of the matter in ethics, which is independent of our views, and which we seek to discover. Unfortunately much of this interesting debate found in the work of McDowell, Wiggins, Putnam, Blackburn and others is not easily accessible to undergraduates. McNaughton presents many of the major issues in ethics by way of a clear exposition of both sides of this argument and assumes no prior knowledge of philosophy. Topics discussed include: moral observation, moral motivation, amoralism and wickedness, moral weakness, cultural relativism and utilitarianism. The book concludes that a convincing case can be made out for a radical form of moral realism in which moral virtue is found, not in the following of correct moral principles, but rather in the development of moral sensitivity. Moral Vision is a clear and engaged introduction to an important, and often troubling, debate. (shrink)

According to the Self-Location Thesis, one’s own location can be among the things that visual experience represents, even when one’s body is entirely out of view. By contrast, the Minimal View denies this, and says that visual experience represents things only as "to the right", etc., and never as "to the right of me". But the Minimal View is phenomenologically inadequate: it cannot explain the difference between a visual experience of self-motion and one of an oppositely moving world. To show (...) this, I argue (i) that these experiences are different in an important respect, (ii) that this difference is genuinely experiential, (iii) that it is visual, (iv) that it is not purely phenomenal, and (v) that it cannot be identified with anything other than the apparent motion of the self. So the Self-Location Thesis is upheld: reports of one’s own motion can correspond to aspects of visual experiences every bit as basic to their contents as the apparent motion or rest of the things one has in view. (shrink)

This Article outlines a vision of responsible innovation and outlines a public policy and implementation strategy for it.

This article reviews the seven “visions” of evolution proposed by Depew and Weber , concluding that each posited relationship between natural selection and self-organization has suited different aims and approaches. In the second section of the article, we show that these seven viewpoints may be collapsed into three fundamentally different ones: natural selection drives evolution; self-organization drives evolution; and natural selection and self-organization are complementary aspects of the evolutionary process. We then argue that these three approaches are not mutually exclusive, (...) since each may apply to different stages of development of different systems. What emerges from our discussion is a more encompassing view: that self-organization proposes what natural selection disposes. (shrink)

Paul Snowdon; XI*—Perception, Vision and Causation, Proceedings of the Aristotelian Society, Volume 81, Issue 1, 1 June 1981, Pages 175–192, https://doi.org/10.

Since it is now broadly acknowledged that ethics should receive early consideration in discourse on emerging technologies, ethical debates tend to flourish even while new fields of technology are still in their infancy. Such debates often liberally mix existing applications with technologies in the pipeline and far-reaching visions. This paper analyses the problems associated with this use of ethics as “preparatory” research, taking discourse on human enhancement in general and on pharmaceutical cognitive enhancement in particular as an example. The paper (...) will outline and discuss the gap between the scientific and technological state of the art and the ethical debates, pointing out epistemic problems in this context. Furthermore, it will discuss the future role of genuine ethical reflection in discourse on human enhancement, arguing also that such discourse needs to include a technology assessment—in the broad sense of the term—which encompasses, inter alia, anthropological perspectives and aspects of social theory. (shrink)

This volume offers a comprehensive philosophical study of Confucian ethics-its basic insights and its relevance to contemporary Western moral philosophy. Distinguished writer and philosopher A. S. Cua presents fourteen essays which deal with various probl.

b>. Computational models of colour vision assume that the biological function of colour vision is to detect surface reflectance. Some philosophers invoke these models as a basis for 'externalism' about perceptual content (content is distal) and 'objectivism' about colour (colour is surface reflectance). In an earlier article (Thompson et al. 1992), I criticized the 'computational objectivist' position on the basis of comparative colour vision: There are fundmental differences among the colour vision of animals and these differences (...) do not converge on the detection of any single type of environmental property. David R. Hilbert (1992) has recently defended computational objectivism against my 'comparative argument;' his arguments are based on the externalist approach to perceptual content originally developed by Mohan Matthen (1988) and on the computationally inspired theory of the evolutionary basis for trichromacy developed by Roger N. Shepard (1990). The present article provides a reply to Hilbert with extensive criticism of both Matthen's and Shepard's theories. I argue that the biological function of colour vision is not to detect surface reflectance, but to provide a set of perceptual categories that can apply to objects in a stable way in a variety of conditions. Comparative research indicates that both the perceptual categories and the distal stimuli will differ according to the animal and its visual ecology; therefore externalism and objectivism must be rejected. (shrink)

Globalization is often seen as a process of universal standardization under the auspices of market economics, technology, and hegemonic power. Resisting this process without endorsing parochial self-enclosure, Fred Dallmayr explores alternative visions that are rooted in distinct vernacular traditions and facilitate cross-cultural learning in an open-ended global arena.

Se comparan las teorías de Marr y Berkeley sobre la visión a partir de las cualidades de Descartes. La descripción de tres niveles de Marr, donde la conciencia está ausente, contrasta con el nivel único de Berkeley construido sobre la conciencia y la experiencia carece de importancia en los momentos esquemáticos y cobra protagonismo en el último paso del proceso de la visión de Marr mediante la noción de marcación. Bajo la premisa de que las descripciones puramente sincrónicas han de (...) ser forzosamente incompletas, se reformula el problema de Molyneux y se reivindica el papel explicativo de la conciencia. (shrink)

This field review discusses several recently published books that are concerned with historical, cultural, philosophical, or sociological aspects of the social sciences and humanities, past and present. It investigates similarities and differences between the various perspectives and approaches, and analyzes how these are informed by different visions of the field of SSH studies. In concluding, the review discusses three recurrent themes that will presumably move in the focus of debate in the near future: the debate on positivism in SSH and (...) its “epistemological others;” the impact of the Cold War on the gestalt of the SSH; and, finally, the adequacy of science, technology, and society approaches to describe techniques and practices in the SSH. (shrink)

A social scientific survey on visions of human/nature relationships in western Europe shows that the public clearly distinguishes not only between anthropocentrism and ecocentrism, but also between two nonanthropocentric types of thought, which may be called “partnership with nature” and “participation in nature.” In addition, the respondents distinguish a form of human/nature relationship that is allied to traditional stewardship but has a more ecocentric content, labeled here as “guardianship of nature.” Further analysis shows that the general public does not subscribe (...) to an ethic of “mastery over nature.” Instead, practically all respondents embrace the image of guardianship, while the more radical relationships of partnership and participation also received significant levels of adherence. The results imply that ethicists should no longer assume that the ethics of the public are merely anthropocentric. Finally, they call into question the idea of a single form of ecocentrism and favor a hermeneutic virtue ethics approach to the study of the interface between ethics and action. (shrink)

In _Action in Perception _Alva No develops and presents a sensorimotor account of vision and of visual consciousness. According to such an account seeing (and indeed perceiving more generally) is analysed as a kind of skilful bodily activity. Such a view is consistent with the emerging emphasis, in both philosophy and cognitive science, on the critical role of embodiment in the construction of intelligent agency. I shall argue, however, that the full sensorimotor model faces three important challenges. The first (...) is to negotiate a path between two prima facie unsatisfactory readings of the central claim that conscious perceptual experience is constituted by knowledge of patterns of sensorimotor dependence. The second is to convince us that the sensorimotor contribution, in such cases, is actually constitutive of perceptual experience rather than merely causally implicated in the origination of such experience.² And the third is to respond to the important challenge raised by what I will dub 'sensorimotor summarizing' models of the relation between conscious experience and richly detailed sensorimotor routines. According to such models³ conscious perceptual experience only rather indirectly reflects the rich detail of our actual sensorimotor engagements, which are instead lightly sampled as a coarse guide, optimized for planning and reasoning, and geared and filtered according to current needs and purposes. (shrink)

Al-Kindi was influenced by two Greek traditions in his attempts to explain vision, light and color. Most obviously, his works on optics are indebted to Euclid and, perhaps indirectly, to Ptolemy. But he also knew some works from the Aristotelian tradition that touch on the nature of color and vision. Al-Kindi explicitly rejects the Aristotelian account of vision in his De Aspectibus, and adopts a theory according to which we see by means of a visual ray emitted (...) from the eye. But in the same work, al-Kindi draws on Philoponus. (shrink)

Visual disturbances are amongst the most commonly reported symptoms after a traumatic brain injury despite vision testing being uncommon at initial clinical evaluation. TBI patients consistently present a wide range of visual complaints, including photophobia, double vision, blurred vision, and loss of vision which can detrimentally affect reading abilities, postural balance, and mobility. In most cases, especially in rural areas, visual disturbances of TBI would have to be diagnosed and assessed by primary care physicians, who lack (...) the specialized training of optometry. Given that TBI patients have a restricted set of visual concerns, an opportunity exists to develop a screening protocol for specialized evaluation by optometrists—one that a primary care physician could comfortably carry out and do so in a short time. Here, we designed a quick screening protocol that assesses the presence of core visual symptoms present post-TBI. The MOBIVIS protocol takes on average 5 min to perform and is composed of only “high-yield” tests that could be performed in the context of a primary care practice and questions most likely to reveal symptoms needing further vision care management. The composition of our proposed protocol and questionnaire are explained and discussed in light of existing protocols. Its potential impact and ability to shape a better collaboration and an integrative approach in the management of mild TBI patients is also discussed. (shrink)

A semiotic theory of systems derived from language would have the purpose of classifying all the systems of linguistic expression: philosophy, ideology, myth, poetry, art, as much as the dream, lapsus, and free association in a pluridimensional matrix that will interact with many diversified fields. In each one of these discourses it is necessary to consider a plurality of questions, the essence of which will only be comprehensible by the totality; it will be necessary to ask, in the first place, (...) what will be the purpose of this language, what function does it fulfill and for which reason has it been constructed. The concept of World vision (WV) is introduced and its relation with Generalized Collective Conscience (GCC) and Particularized Collective Conscience. Culture implies a particular WV. Culture creates GCC. The semantic field is a structure that formalizes the units of a certain culture constituting a portion of the vision of the Reality that owns this culture. An ecological case is explained. (shrink)

This book examines longstanding problems in the theory of vision. Each section begins by looking at the issues as they were raised and discussed by Berkeley. This work is unique in its blend of philosophical and historical perspectives on contemporary problems of readership.

You might reasonably surmise from the title of this paper that I will be discussing a theory of vision. After all, what is a theory of vision but a theory of how the world is connected to our visual representations? Theories of visual perception universally attempt to give an account of how a proximal stimulus (presumably a pattern impinging on the retina) can lead to a rich representation of a three dimensional world and thence to either the recognition (...) of known objects or to the coordination of actions with visual information. Such theories typically provide an effective (i.e., computable) mapping from a 2D pattern to a representation of a 3D scene, usually in the form of a symbol structure. But such a mapping, though undoubtedly the essential purpose of a theory of vision, leaves at least one serious problem that I intend to discuss here. It is this problem, rather than a theory of vision itself, that is the subject of this talk. (shrink)

Vision constitutes an interesting domain, or range of domains, for debate over the extended mind thesis, the idea that minds physically extend beyond the boundaries of the body. In part this is because vision and visual experience more particularly are sometimes presented as a kind of line in the sand for what we might call externalist creep about the mind: once all reasonable concessions have been made to externalists about the mind, visual experience marks a line beyond which (...) lies a safe haven for individualists. Here I want to put a little more pressure on such a view of visual experience, as well as to offer a more constructive, positive argument in defense of the idea of extended vision. (shrink)

Imagine yourself sitting on your front porch, sipping your morning coffee and admiring the scene before you. You see trees, houses, people, automobiles; you see a cat running across the road, and a bee buzzing among the flowers. You see that the flowers are yellow, and blowing in the wind. You see that the people are moving about, many of them on bicycles. You see that the houses are painted different colors, mostly earth tones, and most are one-story but a (...) few are two-story. It is a beautiful morning. Thus the world interfaces with your mind through your senses. There is a strong intuition that we are not disconnected from the world. We and the other things we see around us are part of a continuous whole, and we have direct access to them through vision, touch, etc. However, the philosophical tradition tries to drive a wedge between us and the world by insisting that the information we get from perception is the result of inference from indirect evidence that is about how things look and feel to us. The philosophical problem of perception is then to explain what justifies these inferences. We will focus on visual perception. Figure one presents a crude diagram of the cognitive system of an agent capable of forming beliefs on the basis of visual perception. Cognition begins with the stimulation of the rods and cones on the retina. From that physical input, some kind of visual processing produces an introspectible visual image. In response to the production of the visual image, the cognizer forms beliefs about his or her surroundings. Some beliefs the perceptual beliefs are formed as direct responses to the visual input, and other beliefs are inferred from the perceptual beliefs. The perceptual beliefs are, at the very least, caused or causally influenced by having the image. This is signified by the dashed arrow marked with a large question mark. We will refer to this as the mystery link. Figure one makes it apparent that in order to fully understand how knowledge is based on perception, we need three different theories.. (shrink)

Introduction In 1709 George Berkeley published his first substantial work, An Essay towards a New Theory of Vision. As a contribution to the theory of ...

The indexical thesis says that the indexical terms, “I”, “here” and “now” necessarily refer to the person, place and time of utterance, respectively, with the result that the sentence, “I am here now” cannot express a false proposition. Gerald Vision offers supposed counter-examples: he says, “I am here now”, while pointing to the wrong place on a map; or he says it in a note he puts in the kitchen for his wife so she’ll know he’s home even though (...) he’s gone upstairs for a nap, but then he leaves the house, forgetting to remove the note. The first sentence is false by virtue of “here” not necessarily referring to the place of utterance, the second sentence, by virtue of “now” not necessarily referring to the time of utterance. We argue that these sentences express falsehoods only because the terms are being used demonstratively, not indexically – the distinction pertains not to words simpliciter, but to uses of words. When used indexically, the terms refer in accord with the indexical thesis; but when used demonstratively, their referents depend on how devices of ostension are used with their utterance – pointings, and the like. Thus Vision’s first sentence really says, “I am there now”, referring to the place on the map the finger is pointing to. As for his second sentence, we distinguish the time of utterance or production of a sentence from the time of its uptake. Due to the pragmatics of interpretation, the sentence really says “I” – the person ‘uttering’ the note – “am here” – here where the note is, with the note serving as a kind of proxy ‘finger’ – “now” – where “now” refers to the time of uptake of the note, i.e., when it is read. “I” refers indexically, “here”, demonstratively, and “now”, indexically, but indexically to the time of uptake. Since the sentence is not purely indexical, its falsehood doesn’t threaten the indexical thesis. A similar treatment is given of teletyped messages about the typer’s location. (shrink)

Pure representationalism or intentionalism for phenomenal experience is the theory that all introspectible qualitative aspects of a conscious experience can be analyzed as qualities that the experience non-conceptually represents the world to have. Some philosophers have argued that experiences such as afterimages, phosphenes and double vision are counterexamples to the representationalist theory, claiming that they are non- representational states or have non-representational aspects, and they are better explained in a qualia-theoretical framework. I argue that these states are fully representational (...) states of a certain kind, which I call “automatically non-endorsed representations”, experiential states the veridicality of which we are almost never committed to, and which do not trigger explicit belief or disbelief in the mind of the subject. By investigating descriptive accounts of afterimages by two qualia theorists, I speculate that the mistaken claims of some anti-representationalists might be rooted in confusing two senses of the term “seeming”. (shrink)

Species : visions and values -- Fantasies : seeing without what was within -- Prestiges : illusions in magic and art -- Glamours : demons and virtual worlds -- Images : the reformation of the eyes -- Apparitions : the discernment of spirits -- Sights : King Saul and King Macbeth -- Seemings : philosophical scepticism -- Dreams : the epistemology of sleep -- Signs : vision and the new philosophy.