The Conscious Brain brings neuroscientific evidence to bear on enduring philosophical questions. Major philosophical and scientific theories of consciousness are surveyed, challenged, and extended.

Perceptual experiences inform us about objective properties of things in our environment. But they also have perspectival character in the sense that they differ phenomenally when objects are viewed from different points of view. Contemporary representationalists hold, at a minimum, that phenomenal character supervenes on representational content. Thus, in order to account for perspectival character, they need to indentify a type of representational content that changes in appropriate ways with the perceiver’s point of view. Many representationlists, including Shoemaker and Lycan, (...) argue that such contents are best construed in terms of mind-dependent properties. Other representationalists, including Tye and Dretske, hold that these contents involve only mind-independent properties. Susanna Schellenberg has recently developed an account of perceptual experience that would serve these latter representationalists extremely well. She suggests that we can do justice to the perspectival character of perceptual experience by appeal to representations of a certain type of relational properties, so-called ‘situation-dependent properties.’ In this paper, I critically engage with Schellenberg’s proposal in order to show how mind-independent representationalists can explain perspectival character. I argue that appeal to situation-dependent properties is problematic. I then show that mind-independent representationalists can account for perspectical character by means of scenario contents in Christopher Peacocke’s sense. (shrink)

Students of perception have long puzzled over a range of cases in which perception seems to tell us distinct, and in some sense conflicting, things about the world. In the cases at issue, the perceptual system is capable of responding to a single stimulus — say, as manifested in the ways in which subjects sort that stimulus — in different ways. This paper is about these puzzling cases, and about how they should be characterized and accounted for within a general (...) theory of perception. After rehearsing the sort of case at issue (§1), I’ll examine critically some of the strategies by which philosophers and perceptual psychologists have attempted to account for them (§2). Finally, I’ll present an alternative computational account of the puzzle cases, argue that this view is superior to its competitors, and examine some of its implications (§3). (shrink)

In 1995, in my book, Ten Problems of Consciousness, I proposed a version of the theory of phenomenal consciousness now known as representationalism. The present book, in part, consists of a further development of that theory along with replies to common objections. It is also concerned with two prominent challenges for any reductive theory of consciousness: the explanatory gap and the knowledge argument. In addition, it connects representationalism with two more general issues: the nature of color and the location of (...) the phylogenetic dividing line between those creatures that are phenomenally conscious and those that are not. (shrink)

I argue that perception is necessarily situation-dependent. The way an object is must not just be distinguished from the way it appears and the way it is represented, but also from the way it is presented given the situational features. First, I argue that the way an object is presented is best understood in terms of external, mind-independent, but situation-dependent properties of objects. Situation-dependent properties are exclusively sensitive to and ontologically dependent on the intrinsic properties of objects, such as their (...) shape, size, and color, and the situational features, such as the lighting conditions and the perceiver’s location in relation to the perceived object. Second, I argue that perceiving intrinsic properties is epistemically dependent on representing situation-dependent properties. Recognizing situation-dependent properties yields four advantages. It makes it possible to embrace the motivations that lead to phenomenalism and indirect realism by recognizing that objects are presented a certain way, while holding on to the intuition that subjects directly perceive objects. Second, it acknowledges that perceptions are not just individuated by the objects they are of, but by the ways those objects are presented given the situational features. Third, it allows for a way to accommodate the fact that there is a wide range of viewing conditions or situational features that can count as normal. Finally, it makes it possible to distinguish perception and thought about the same object with regard to what is represented. (shrink)

Does a penny viewed at an angle in some sense look elliptical, as though projected on a two-dimensional surface? Many philosophers have said such things, from Malebranche (1674/1997) and Hume (1739/1978), through early 20th-century sense-data theorists, to Tye (2000) and Noë (2004). I confess that it doesn't seem this way to me, though I'm somewhat baffled by the phenomenology and pessimistic about our ability to resolve the dispute. I raise geometrical complaints against the view and conjecture that views of this (...) sort draw some of their appeal from over-analogizing visual experience to painting or photography. Theorists writing in contexts where vision is typically analogized to less-projective media--wax signet impressions in ancient Greece, stereoscopy in introspective psychology circa 1900--are substantially less likely to attribute such projective distortions to visual appearances. (shrink)

I offer an explanation of how subjects are able to perceive the intrinsic spatial properties of objects, given that subjects always perceive from a particular location. The argument proceeds in two steps. First, I argue that a conception of space is necessary to perceive the intrinsic spatial properties of objects. This conception of space is spelled out by showing that perceiving intrinsic properties requires perceiving objects as the kind of things that are perceivable from other locations. Second, I show that (...) having such a conception of space presupposes that a subject represent her location in relation to perceived objects. More precisely the thesis is that a subject represents her location as the location from which she both perceives objects and would act in relation to objects were she to act. So I argue that perception depends on the capacity to know what it would be to act in relation to objects. (shrink)

Frequently, we learn of the locations of things and events in our environment by means of hearing. Hearing, I argue, is a locational mode of perceiving with a robustly spatial phenomenology. I defend three proposals. First, audition furnishes one with information about the locations of things and happenings in one’s environment because auditory experience itself has spatial content—auditory experience involves awareness of space. Second, we hear the locations of things and events by or in hearing the locations of their sounds. (...) Third, we auditorily experience sounds themselves as having relatively stable distal locations. I reject skepticism about spatial audition and auditory experience tracing to Strawson’s Individuals , and suggest that spatial auditory experience grounds a form of perceptual access to objects and events that is critical to negotiating one’s environment. (shrink)

When we see an object, we also represent those parts of it that are not visible. The question is how we represent them: this is the problem of amodal perception. I will consider three possible accounts: (a) we see them, (b) we have non-perceptual beliefs about them and (c) we have immediate perceptual access to them, and point out that all of these views face both empirical and conceptual objections. I suggest and defend a fourth account, according to which we (...) represent the occluded parts of perceived objects by means of mental imagery. This conclusion could be thought of as a (weak) version of the Strawsonian dictum, according to which “imagination is a necessary ingredient of perception itself”. (shrink)

The paper offers a partial, broad-stroke sketch of visual perception, and argues that certain kinds of normal visual misperceptions are systematic and widespread.

A common objection to sense-datum theories of perception is that they cannot give an adequate account of the fact that introspection indicates that our sensory experiences are directed on, or are about, the mind-independent entities in the world around us, that our sense experience is transparent to the world. In this paper I point out that the main force of this claim is to point out an explanatory challenge to sense-datum theories.

Like dreaming, hallucination has been a formative trope for modern philosophy. The vivid, often tragic, breakdown in the mind’s apparent capacity to disclose reality has long served to support a paradoxical philosophical picture of sensory experience. This picture, which of late has shaped the paradigmatic empirical understanding the senses, displays sensory acts as already complete without the external world; complete in that the direct objects even of veridical sensory acts do not transcend what we could anyway hallucinate. Hallucination is thus (...) the mother of Representationalism, which insists that it is mental intermediaries that make other.. (shrink)

It is frequently alleged that a round plate viewed from an oblique angle looks elliptical, and that when one tree is in front of another that is the same intrinsic size, the front one looks larger than the rear one. And yet there is also a clear sense in which the plate viewed from an angle looks round, and a clear sense in which the two trees look to be the same size. According to the Dual Content Theory (DCT), what (...) explains these and other similar phenomena is that perceptual experiences present us with two different sorts of spatial properties: intrinsic and perspectival spatial properties. I will argue that the Dual Content Theory is false because it rests on flawed phenomenological descriptions of the experience of spatial properties. The only conditions under which a plate tilted away and an ellipse look alike, or two objects which are different in size look the same size, is when at least one of the objects being compared is misperceived. I will consider several responses to the arguments I present, and conclude by suggesting that abandoning DCT would constitute an improvement upon Noë’s enactive theory of perception. (shrink)

Visual experience is shaped by a number of factors that are independent of the external objects that we perceive—factors like lighting, angle of view, and the sensitivities of photoreceptors in the retina. This paper seeks to catalog, analyze, and explain the fluctuations in visual phenomenology that are due to such factors.

This paper develops an appearance view of perception (focusing on vision). When we see an object, we see it by having it appear some way to us. We see the object, not the appearance; but we see the object via the appearance. The appearance is subjectively conditioned: aspects of it depend on attributes of the subject. We mentally have the appearance and can reflect on it as an appearance. But in the primary instance, of veridical perception, it is the object (...) that we focus on and experience. I contrast this view with naive realism (sometimes called disjunctivism) (Brewer, Campbell, Noe) and with intentionalist or representationalist views, which I call the physical content view (Dretske, Tye, Crane, Hill, Burge). I agree with these views in rejecting sense-data intermediaries and in affirming direct perception, but I argue that direct perception occurs via appearances, making mine a critical direct realism. The other views attempt to explain the spatial content of perception (shape, size, distance) entirely through the physical properties of objects and their physical relation to the perceiver (viewing position). I argue instead that there are ineliminably subjective aspects of normal spatial perception, which are systematically manifested as a lack of full phenomenal constancy. This systematic underconstancy can’t be accounted for at all by a consistent naive realism; for the physical content view, it requires that most of our ordinary perception is classified as illusory, violating the spirit of that view. Accepting phenomenal underconstancy as pervasive, I suggest that our ability to perceive the mind-independent properties of objects depends on developed conceptual abilities. In the final section, I compare my appearance view with the adverbialism of Chisholm and the critical direct realism of Roy Wood Sellars. (shrink)

Many of the objects that we perceive have an important characteristic: When they move, they change shape. For instance, when you watch a person walk across a room, her body constantly deforms. I suggest that we exercise a type of perceptual constancy in response to changes of this sort, which I call structure constancy. In this paper I offer an account of structure constancy. I introduce the notion of compositional structure, and propose that structure constancy involves perceptually representing an object (...) as retaining its compositional structure over time. I argue that compositional structure is represented in visual phenomenology, and I also assemble empirical evidence in support of the claim that compositional structure is recovered by the visual system. Finally, I draw out consequences of this account. I argue that structure constancy has implications for the predictive capacities of perception, and that the phenomenon places important constraints on viable accounts of both the format and reference frame of visual experience. (shrink)

This article develops a view of shape representation both in visual experience and in subpersonal visual processing. The view is that, in both cases, shape is represented in a ‘layered’ manner: an object is represented as having multiple shape properties, and these properties have varying degrees of abstraction. I argue that this view is supported both by the facts about visual phenomenology and by a large collection of evidence in perceptual psychology. Such evidence is provided by studies of shape discriminability, (...) apparent motion, multiple-object tracking, and structure-from-motion. Recent neuroscientific work has also corroborated this psychophysical evidence. Finally, I draw out implications of the layered view for processes of concept acquisition. 1 Introduction2 Metric Properties andShape Properties3 Metric Views4 Against Metric Views of Visual Shape Experience5 The Visual System Uses Abstract Shape Properties6 Against Metric Views of Visual Shape Representation7 Neural Underpinnings of Abstract Shape Perception8 Implications. (shrink)

Tyler Burge presents an original study of the most primitive ways in which individuals represent the physical world. By reflecting on the science of perception and related psychological and biological sciences, he gives an account of constitutive conditions for perceiving the physical world, and thus aims to locate origins of representational mind.

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)

The problem of amodal perception is the problem of how we represent features of perceived objects that are occluded or otherwise hidden from us. Bence Nanay (2010) has recently proposed that we amodally perceive an object's occluded features by imaginatively projecting them into the relevant regions of visual egocentric space. In this paper, I argue that amodal perception is not a single, unitary capacity. Drawing appropriate distinctions reveals amodal perception to be characterized not only by mental imagery, as Nanay suggests, (...) but also by genuinely visual representations as well as beliefs. I conclude with some brief remarks on the role of object-directed bodily action in conferring a sense of unseen presence on an object's occluded features. (shrink)

Physical objects are such things as stones, tables, trees, people and other animals: the persisting macroscopic constituents of the world we live in. therefore expresses a commonsense commitment to physical realism: the persisting macroscopic constituents of the world we live in exist, and are as they are, quite independently of anyone.

Long tradition in philosophy and in empirical psychology has it that the perceptual recovery of enduring objective size and shape proceeds through initial spatial appearance experiences—like the sensed changing visual field size of a receding car, or the shifting shape appearance of a coin as it rotates in depth. The present paper carefully frames and then critically examines such proposals. It turns out that these are contingent, empirical matters, requiring close examination of relevant research in perception science in order to (...) decide. The paper concludes with extended discussions of the empirical study of the perception of slant, size, and shape. (shrink)

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

This volume presents a selection of essays by the leading philosopher Christopher S. Hill. Together, they address central philosophical issues related to four key concerns: the nature of truth; the relation between experiences and brain states; the relation between experiences and representational states; and problems concerning knowledge.

Do you dream in color? If you answer Yes, how can you be sure? Before you recount your vivid memory of a dream featuring all the colors of the rainbow, consider that in the 1950s researchers found that most people reported dreaming in black and white. In the 1960s, when most movies were in color and more people had color television sets, the vast majority of reported dreams contained color. The most likely explanation for this, according to the philosopher Eric (...) Schwitzgebel, is not that exposure to black-and-white media made people misremember their dreams. It is that we simply don't know whether or not we dream in color. In Perplexities of Consciousness, Schwitzgebel examines various aspects of inner life and argues that we know very little about our stream of conscious experience. Drawing broadly from historical and recent philosophy and psychology to examine such topics as visual perspective, and the unreliability of introspection, Schwitzgebel finds us singularly inept in our judgments about conscious experience. (shrink)

A further development of Tye's theory of phenomenal consciousness along with replies to common objections.

This book presents a comprehensive theory of consciousness. The initial chapter distinguishes six main forms of consciousness and sketches an account of each one. Later chapters focus on phenomenal consciousness, consciousness of, and introspective consciousness. In discussing phenomenal consciousness, Hill develops the representational theory of mind in new directions, arguing that all awareness involves representations, even awareness of qualitative states like pain. He then uses this view to undercut dualistic accounts of qualitative states. Other topics include visual awareness, visual appearances, (...) emotional qualia, and meta-cognitive processing. This important work will interest a wide readership of students and scholars in philosophy of mind and cognitive science. (shrink)

This book explores the mismatch between perception and physical reality, and describes the many factors that influence the perception of space including the ...

"Perception is not something that happens to us, or in us," writes Alva Noe. "It is something we do." In Action in Perception, Noe argues that perception and perceptual consciousness depend on capacities for action and thought — that ...