Ned Block

This is a charming and engaging book that combines careful attention to the phenomenology of experience with an appreciation of the psychology and neuroscience of perception. In some of its aimsfor example, to show problems with a rigid version of a view of visual perception as an inverse optics process of constructing a static 3-D representation from static 2-D information on the retina--it succeeds admirably. As No points out, vision is a process that depends on interactions between the perceiver and the environment and involves contributions from sensory systems other than the eye. He is at pains to note that vision is not passive. His analogy with touch is to the point: touch involves skillful probing and movement, and so does vision, although less obviously and in my view less centrally so. This much is certainly widely accepted among vision scientistsalthough mainstream vision scientists (represented, for example, by Stephen Palmers excellent textbook²) view these points as best seen within a version of the inverse optics view that takes inputs as non-static and as including motor instructions (for example, involving eye movements and head movements).³ The kind of point that No raises is viewed as important at the margins, but as not disturbing the main lines of the picture of vision that descendswith many changesfrom the pioneering work of David Marr in the 1980s (and before him, from Helmholtz). But No shows little interest in mainstream vision science, focusing on non-mainstream ideas in the science of perception, specifically ideas from the anti-representational psychologist J.J. Gibson, and also drawing on Wittgenstein and the phenomenology tradition. There is a sense throughout the book of revolution, of upsetting the applecart. This is a review from the point of view of the applecart.

One of the most important issues concerning the foundations ofconscious perception centerson thequestion of whether perceptual consciousness is rich or sparse. The overflow argument uses a form of ‘iconic memory’ toarguethatperceptual consciousnessisricher (i.e.,has a higher capacity) than cognitive access: when observing a complex scene we are conscious of more than we can report or think about. Recently, the overflow argumenthas been challenged both empirically and conceptually. This paper reviews the controversy, arguing that proponents of sparse perception are committed to the postulation of (i) a peculiar kind of generic conscious representation that has no independent rationale and (ii) an unmotivated form of unconscious representation that in some cases conflicts with what we know about unconscious representation.

This volume of Ned Block's writings collects his papers on consciousness, functionalism, and representationism. A number of these papers treat the significance of the multiple realizability of mental states for the mind-body problem -- a theme that has concerned Block since the 1960s. One paper on this topic considers the upshot for the mind-body problem of the possibility of a robot that is functionally like us but physically different -- as is Commander Data of _Star Trek's_ second generation. The papers on consciousness treat such conceptual issues as phenomenal versus access consciousness, Dennett's theory of consciousness, and the function of consciousness, as well as such empirical matters as "How Not to Find the Neural Correlate of Consciousness," and an argument that there are distinct neural correlates for access consciousness and phenomenal consciousness. Turning to the mind-body problem, Block defends physicalism against Max Black's argument concerning phenomenal modes of presentation. The papers on representationism consider "mental paint" as well as the "Inverted Earth" thought experiment -- a world in which colors are reversed but there is a compensating reversal in the words that are used to describe them. _Consciousness, Function, and Representation_, bringing together papers that have appeared primarily in journals and conference proceedings, can be regarded as Block's most complete statement of his positions on consciousness

Michael Tye's response to my “Grain” (Block ) and “Windows” (Block ) raises general metaphilosophical issues about the value of intuitions and judgments about one's perceptions and the relations of those intuitions and judgments to empirical research, as well as specific philosophical issues about the relation between seeing, attention and de re thought. I will argue that Tye's appeal to what is (§. 2) “intuitively obvious, once we reflect upon these cases” (“intuition”) is problematic. I will also argue that first person judgments can be problematic when used on their own as Tye does but can be valuable when integrated with empirical results

The "great debate" in cognitive science today is about the nature of mental images. One side says images are basically pictures in the head. The other side says they are like the symbol structures in computers. If the picture-in-the-head theorists are right, then computers will never be able to think like people.This book contains the most intelligible and incisive articles in the debate, articles by cognitive psychologists, computer scientists and philosophers. The most exciting imagery phenomena are described, phenomena that indicate that mental images can be rotated and scanned, that smaller images are harder to see than larger ones, that when mental images are made larger they eventually overflow, that the "screen" they overflow from has a determinable shape (elliptical), and that this "screen" subtends a determinate visual angle, the angle of vision of the mind's eye.Such experiments cry out for explanation. If images are pictures in the head, who (or what) looks at them? Why haven't brain scientists found them? Such questions are the subject of the great debate.IMAGERY is an excellent choice for courses in cognitive psychology, perception: artificial intelligence, computer science; philosophy of mind, of psychology and of science; minds and machines, science and society.Contributors include: Roger Brown and Richard Herrnstein (on the work of Roger N. Shepard), Daniel Dennett, Jerry Fodor, Robert Schwartz, Stephen Kosslyn, Steven Pinker, George Smith, Steven Shwartz, and Zenon Pylyshyn,

The explanatory gap . Consciousness is a mystery. No one has ever given an account, even a highly speculative, hypothetical, and incomplete account of how a physical thing could have phenomenal states. Suppose that consciousness is identical to a property of the brain, say activity in the pyramidal cells of layer 5 of the cortex involving reverberatory circuits from cortical layer 6 to the thalamus and back to layers 4 and 6,as Crick and Koch have suggested for visual consciousness. .) Still, that identity itself calls out for explanation! Proponents of an explanatory gap disagree about whether the gap is permanent. Some say that we are like the scientifically naive person who is told that matter = energy, but does not have the concepts required to make sense of the idea. If we can acquire these concepts, the gap is closable. Others say the gap is uncloseable because of our cognitive limitations. Still others say that the gap is a consequence of the fundamental nature of consciousness.

Dehaene and Naccache, Dennett and Jack and Shallice “see convergence coming from many different quarters on a version of the neuronal global workspace model†(Dennett, p. 1). (Boldface references are to papers in this volume.) On the contrary, even within this volume, there are commitments to very different perspectives on consciousness. And these differing perspectives are based on tacit differences in philosophical starting places that should be made explicit.  Indeed, it is not clear that different uses of “consciousness†and “awareness†in this volume can be taken to refer to the same phenomenon. More specifically, I think there are three different concepts of consciousness in play in this issue. The global workspace model makes much more sense on one of these than on the others

Mental (or semantic) holism is the doctrine that the identity of a belief content (or the meaning of a sentence that expresses it) is determined by its place in the web of beliefs or sentences comprising a whole theory or group of theories. It can be contrasted with two other views: atomism and molecularism. Molecularism characterizes meaning and content in terms of relatively small parts of the web in a way that allows many different theories to share those parts. For example, the meaning of 'chase' might be said by a molecularist to be try to catch. Atomism characterizes meaning and content in terms of none of the web; it says that sentences and beliefs have meaning or content independently of their relations to other sentences or beliefs. One major motivation for holism has come from reflections on the natures of confirmation and learning. As Quine (1953) observed, claims about the world are confirmed not individually, but only in conjunction with theories of which they are a part. And typically, one cannot come to understand scientific claims without understanding a significant chunk of the theory of which they are a part. For example, in learning the Newtonian concepts of 'force', 'mass', kinetic energy' and 'momentum', one doesn't learn any definitions of these terms in terms that are understood beforehand, for there are no such definitions. Rather, these theoretical terms were all learned together in conjunction with procedures for solving problems. The major problem with holism is that it threatens to make generalization in psychology virtually impossible. If the content of any state depends on all others, it would be extremely unlikely that any two believers would ever share a state with the same content. Moreover, holism would appear to conflict with our ordinary conception of reasoning. What sentences one accepts influence what one infers. if i accept a sentence and then later reject it, i thereby change the inferential role of that sentence, so the meaning of what i accept wouldn't be the same as what i later reject. but then it would be difficult to understand on this view how one could rationally --or even irrationally!-- change one's mind. and agreement and translation are also problematic for much the same reason. holists have responded (1) by proposing that we should think not in terms of "same/different" meaning but in terms of a gradient of similarity of meaning, (2) by proposing "two factor" theories or (3) by simply accepting the consequence that there is no real difference between changing meanings and changing beliefs.

O'Regan and Noe declare that the qualitative character of experience is constituted by the nature of the sensorimotor contingencies at play when we perceive. Sensorimotor contingencies are a highly restricted set of input-output relations. The restriction excludes contingencies that don’t essentially involve perceptual systems. Of course if the ‘sensory’ in ‘sensorimotor’ were to be understood mentalistically, the thesis would not be of much interest, so I assume that these contingencies are to be understood non-mentalistically. Contrary to their view, experience is a matter of what mediates between input and output, not input-output relations all by themselves. However, instead of mounting a head-on collision with their view, I think it will be more useful to consider a consequence of their view that admits of obvious counterexamples. The consequence consists of two claims: (1) any two systems that share that highly restricted set of input-output relations are therefor experientially the same and (2) conversely, any two systems that share experience must share these sensorimotor contingencies. Once stated, the view is so clearly wrong that my ascription of it to them might be challenged. At least it is a consequence of a major strand in their view. Perhaps this will be an opportunity for them to disassociate themselves from it. I will limit myself to (1)