One standard objection to the view that phenomenal experience is functionally determined is based upon what has come to be called ‘The Absent Qualia Hypothesis’, the idea that there could be a person or a machine that was functionally exactly like us but that felt or consciously experienced nothing at all. Advocates of this hypothesis typically maintain that we can easily imagine possible systems that meet the appropriate functional specifications but that intuitively lack any phenomenal consciousness. Ned Block, for example, (...) asks us to suppose that a billion Chinese people are each given a two-way radio with which to communicate with one another and with an artificial body. The movements of the body are controlled by the radio signals, and the signals themselves are made in accordance with instructions the Chinese people receive from a vast display in the sky which is visible to all of them. The instructions are such that the participating Chinese people together realize whatever programs the functionalist supposes underlie human phenomenal experience. (shrink)

At the very heart of the mind-body problem is the question of the nature of consciousness. It is consciousness, and in particular _phenomenal_ consciousness, that makes the mind-body relation so deeply perplexing. Many philosophers hold that no defi nition of phenomenal consciousness is possible: any such putative defi nition would automatically use the concept of phenomenal consciousness and thus render the defi nition circular. The usual view is that the concept of phenomenal consciousness is one that must be explained by (...) means of specifi c examples and associated comments. (shrink)

Qualia inversion thought experiments are ubiquitous in contemporary philosophy of mind. The most popular kind is one or another variant of Locke's hypothetical case of.

Thanks largely to Daniel Dennett, I am a recent convert to what many will regard as the shocking hypothesis that qualia do not exist. This admission is not quite a confident sighting of that rarest of philosophical birds, an unequivocally sound and valid argument. For one thing, I have, like many, been frustrated by and suspicious of philosophers' use of qualia for some time, and have often wished them dead ; so I was an easy mark. More to the point, (...) I was persuaded by Dennett without being persuaded by his arguments. This is not intended as a confession of a Kirkegaardian penchant for preferring to believe the conclusions of bad arguments. Dennett enabled me finally to kick qualia out of my private ontology by providing, in the later sections of his “Quining Qualia”, an alternative conceptual vocabulary for talking about the contents of perceptual and reflective experience that genuinely makes no appeal, surreptitious or otherwise, to qualia. Furthermore, Dennett's most general motivations for banishing qualia—the convictions that there is no compelling evidence for them, that they serve no reliable explanatory purpose and that the hypothesis of their non-existence dissolves some otherwise wrenching philosophical dilemmas—are the right ones, and his paper made this clear to me. However, I feel the need to quine qualia again for myself, because I want them to stay dead, and am afraid that, due to some infelicities in his argument, Dennett has only wounded them. (shrink)

endorsed one kind of inverted spectrum hypothesis and rejected another. This paper argues that the kind of inverted spectrum hypothesis that Wittgenstein endorsed is the thin end of the wedge that precludes a Wittgensteinian critique of the kind of inverted spectrum hypothesis he rejected. The danger of the dangerous kind is that it provides an argument for qualia, where qualia are contents of experiential states which cannot be fully captured in natural language. I will pinpoint the difference between the innocuous (...) and dangerous scenarios that matters for the argument for qualia, give arguments in favor of the coherence and possibility of the dangerous scenario, and try to show that some standard arguments against inverted spectra are ineffective against the version of the dangerous scenario I will be advocating. The leading idea of the paper is that an argument for qualia based on spectrum inversion does not require that the inversion be behaviorally indistinguishable. At one crucial point, I will rely on a less controversial version of an argument I gave in Block. Wittgenstein's views provide a convenient starting point for a paper that is much more about qualia than about Wittgenstein. (shrink)

Qualia include the ways things look, sound and smell, the way it feels to have a pain; more generally, what it's like to have mental states. Qualia are experiential properties of sensations, feelings, perceptions and, in my view, thoughts and desires as well. But, so defined, who could deny that qualia exist? Yet, the existence of qualia is controversial. Here is what is controversial: whether qualia, so defined, can be characterized in intentional, functional or purely cognitive terms. Opponents of qualia (...) think that the content of experience is intentional content, or that experiences are functionally definable, or that to have a qualitative state is to have a state that is monitored in a certain way or accompanied by a thought to the effect that I have that state. If we include the idea that experiential properties are not intentional or functional or purely cognitive in the definition of ` qualia ', then it is controversial whether there are qualia. (shrink)

The problem of the richness of visual experience is that of finding principled grounds for claims about how much of the world a person actually sees at any given moment. It is argued that there are suggestive parallels between the two-component analysis of experience defended by Wilfrid Sellars, and certain recently advanced information processing accounts of visual perception. Sellars' later account of experience is examined in detail, and it is argued that there are good reasons in support of the claim (...) that the sensory nonconceptual content of experience can vary independently of conceptual awareness. It is argued that the Sellarsian analysis is not undermined by recent work on change blindness and related phenomena; a model of visual experience developed by Ronald Rensink is shown to be in essential harmony with the framework provided by Sellars, and provides a satisfactory answer to the problem of the richness of visual experience. (shrink)

A Bradford Book The MIT Press Cambridge, Massachusetts London, England.

Philosophers have long struggled to understand our perceptual experience of temporal properties such as succession, persistence and change. Indeed, strikingly, a number have felt compelled to deny that we enjoy such experience. Philosophical puzzlement arises as a consequence of assuming that, if one experiences succession or temporal structure at all, then one experiences it at a moment. The two leading types of theory of temporal awareness—specious present theories and memory theories—are best understood as attempts to explain how temporal awareness is (...) possible within the constraints of this principle. I argue that the principle is false. Neither theory of temporal awareness can be made workable unless it is rejected. Our experience of temporal phenomena cannot be understood if we attempt to break experience down into instantaneous slices. In order to understand the perception of temporal properties we must look beyond the instant. (shrink)

What is Consciousness For? Lee Pierson and Monroe Trout Copyright © 2005 Abstract: The answer to the title question is, in a word, volition. Our hypothesis is that the ultimate adaptive function of consciousness is to make volitional movement possible. All conscious processes exist to subserve that ultimate function. Thus, we believe that all conscious organisms possess at least some volitional capability. Consciousness makes volitional attention possible; volitional attention, in turn, makes volitional movement possible. There is, as far as we (...) know, no valid theoretical argument that consciousness is needed for any function other than volitional movement and no convincing empirical evidence that consciousness performs any other ultimate function. Consciousness, via volitional action, increases the likelihood that an organism will direct its attention, and ultimately its movements, to whatever is most important for its survival and reproduction. (shrink)

Recently some philosophers interested in consciousness have begun to turn their attention to the question of what evolutionary advantages, if any, being conscious might confer on an organism. The issue has been pressed in recent dicussions involving David Chalmers, Todd Moody, Owen Flanagan and Thomas Polger, Daniel Dennett, and others. The purpose of this essay is to consider some of the problems that face anyone who wants to give an evolutionary explanation of consciousness. We begin by framing the problem in (...) the context of some current debates. Then we. (shrink)

It is the ambition of evolutionary psychology to explain how the basic features of human mental life came to be selected because of their contribution to biological survival. Counted among the most basic must be the subjective qualities of conscious sensory experience: the felt redness we experience on looking at a ripe tomato, the felt saltiness on tasting an anchovy, the felt pain on being pricked by a thorn. But, as many theorists acknowledge, with these qualia, the ambition of evolutionary (...) psychology may have met its match. Everyone agrees that a trait can only contribute to an organism's biological survival in so far as it operates in the public domain. Yet almost everyone also agrees that the subjective quality of sensory experience is (at least for all practical purposes) private and without external influence. Then, maybe we must either concede that the subjective quality of sensations cannot after all have been determined by selection (even if this is theoretically depressing) or else demonstrate that the quality of sensations is not as private as it seems to be (even if this is intuitively unconvincing). No. I believe neither of these solutions to the puzzle is in fact the right one. I argue instead that the truth is that the quality of sensations has indeed been shaped by selection in the past, despite the fact that it is today effectively private. And this situation has come about as a result of a remarkable evolutionary progression, whereby the primitive activity of sensing slowly became "privatized" - that is to say, removed from the domain of overt public behavior and transformed into a mental activity that is now, in humans, largely if not exclusively internal to the subject's mind. (shrink)

Dennett argues that we can be mistaken about our own conscious experience. Despite this, he repeatedly asserts that we can or do have unchallengeable authority of some sort in our reports about that experience. This assertion takes three forms. First, Dennett compares our authority to the authority of an author over his fictional world. Unfortunately, that appears to involve denying that there are actual facts about experience that subjects may be truly or falsely reporting. Second, Dennett sometimes seems to say (...) that even though we may be mistaken about what our conscious experience is, our reports about. (shrink)

Philosophers tend to assume that we have excellent knowledge of our own current conscious experience or 'phenomenology'. I argue that our knowledge of one aspect of our experience, the experience of visual imagery, is actually rather poor. Precedent for this position is found among the introspective psychologists of the late nineteenth and early twentieth centuries. Two main arguments are advanced toward the conclusion that our knowledge of our own imagery is poor. First, the reader is asked to form a visual (...) image, and it is expected that answering questions about certain basic features of that experience will be difficult. If so, it seems reasonable to suppose that people could be mistaken about those basic features of their own imagery. Second, it is observed that although people give widely variable reports about their own experiences of visual imagery, differences in report do not systematically correlate with differences on tests of skills that psychologists have often supposed to require visual imagery, such as mental rotation, visual creativity, and visual memory. (shrink)

The idea that we have special access to our own mental states has a distinguished philosophical history. Philosophers as different as Descartes and Locke agreed that we know our own minds in a way that is quite different from the way in which we know other minds. In the latter half of the twentieth century, however, this idea carne under serious attack, first from philosophy and more recently from developmental psychology. The attack from developmental psychology arises from the growing body (...) of work on “mindreading,” the process of attributing mental states to people. During the last fifteen years, the processes underlying rnindreading have been a major focus of attention in cognitive and developmental psychology. Most of this work has been concerned with the processes underlying the attribution of mental states toother people.However, a number of psychologists and philosophers have also proposed accounts of the mechanisms underlying the attribution of mental states tooneself.This process ofreading one's own mindorbecoming self-awarewill be our primary concern in this paper. (shrink)

It is commonplace for both philosophers and cognitive scientists to express their allegiance to the "unity of consciousness". This is the claim that a subject’s phenomenal consciousness, at any one moment in time, is a single thing. This view has had a major influence on computational theories of consciousness. In particular, what we call single-track theories dominate the literature, theories which contend that our conscious experience is the result of a single consciousness-making process or mechanism in the brain. We argue (...) that the orthodox view is quite wrong: phenomenal experience is not a unity, in the sense of being a single thing at each instant. It is a multiplicity, an aggregate of phenomenal elements, each of which is the product of a distinct consciousness-making mechanism in the brain. Consequently, cognitive science is in need of a multi-track theory of consciousness; a computational model that acknowledges both the manifold nature of experience, and its distributed neural basis. (shrink)

What is a person, and how can a person come to know that she is a person identical to herself over time ? The article defends the view that the sense of being oneself in this sense consists in the ability to consciously affect oneself : in the memory of having affected oneself, joint to the consciousness of being able to affect oneself again. In other words, being a self requires a capacity for metacognition (control and monitoring of one's own (...) internal states). This view is compatible with the hypothesis that the self is a dynamic representation emerging out of a higher level control system, - valuation control - whose articulation with control of plans and perceptual/motor control is discussed in the context of normal and pertrubed agency. (shrink)

This article defends two theses: that a mental state is conscious if and only if it has phenomenal character, i.e., if and only if there is something it is like for the subject to be in that state, and that all state consciousness involves self-consciousness, in the sense that a mental state is conscious if and only if its possessor is, in some suitable way, conscious of being in it. Though neither of these theses is novel, there is a dearth (...) of direct arguments for them in the scholarly literature and the relationship between them has so far gone underrecognized. This article attempts to remedy this lack, advancing the claim that if all conscious states have phenomenal character, then all state consciousness involves self-consciousness. (shrink)

The concept of the self is embedded in a web of relationships of other concepts and phenomena such as consciousness, self-consciousness, personal identity and the mind–body problem. The article follows the ontological and epistemological roles of the concept of selfconsciousness and the structural co-implication of consciousness and self-consciousness from Descartes and Locke to Kant and Sartre while delineating its subject matter from related inquiries into the relationship between the mind and the body, personal identity, and the question whether consciousness is (...) an irreducible reality sui generis or essentially a neurobiological entity. Over the course of its history, the modern self turns out to become an ever more elusive phenomenon, while its roles as a bearer of individual responsibility and as a subject of reflective endorsement of the truth become ever more pronounced. (shrink)

Confronted with the apparent explanatory gap between physical processes and consciousness, there are many possible reactions. Some deny that any explanatory gap exists at all. Some hold that there is an explanatory gap for now, but that it will eventually be closed. Some hold that the explanatory gap corresponds to an ontological gap in nature.

Brain-centered theories of consciousness seem to face insuperable difficulties. While some philosophers now doubt that the hard problem of consciousness will ever be solved, others call for radically new approaches to conscious experience. In this article I resurrect a largely forgotten approach to consciousness known as neorealism. According to neorealism, consciousness is merely a part, or cross-section, of the environment. Neorealism implies that all conscious experiences, veridical or otherwise, exist outside of the brain and are wholly independent of being perceived (...) or not; nonveridical perceptions of the environment over an arbitrarily short period of time are supposed to be objective constituents of the environment over a more extended time scale. I argue here that neorealism fares at least as well as brain-centered theories of consciousness on a number of fundamental issues. On one fundamental issue—the nature of the relation between veridical and nonveridical perceptions—neorealism outperforms its competitors. (shrink)

Are there different constraints on theories of conscious experience as against theories of conscious propositional thought? Is what is problematic or puzzling about each of these phenomena of the same, or of different, types? And to what extent is it plausible to think that either or both conscious experience and conscious thought involve some sort of selfreference? In pursuing these questions I shall also explore the prospects for a defensible form of eliminativism concerning conscious thinking, one that would leave the (...) reality of conscious experience untouched. In the end, I shall argue that while there might be no such thing as conscious judging or conscious wanting, there is (or may well be) such a thing as conscious generic thinking. (shrink)

Traditionally, perceptual experiences—for example, the experience of seeing a cat—were thought to have two quite distinct components. When one sees a cat, one’s experience is “about” the cat: this is the representational or intentional component of the experience. One’s experience also has phenomenal character: this is the sensational component of the experience. Although the intentional and sensational components at least typically go together, in principle they might come apart: the intentional component could be present without the sensational component or vice (...) versa. (shrink)

The greatest chasm in the philosophy of mind--maybe even all of philosophy-- divides two perspectives on consciousness. The two perspectives differ on whether there is anything in the phenomenal character of conscious experience that goes beyond the intentional, the cognitive and the functional. A convenient terminological handle on the dispute is whether there are.

from non-conscious components by positing that consciousness is a universal primitive. For example, the double aspect theory of information holds that infor- mation has a phenomenal aspect. How then do you get from phenomenal infor- mation to human consciousness? This paper proposes that an entity is conscious to the extent it amplifies information, first by trapping and integrating it through closure, and second by maintaining dynamics at the edge of chaos through simul- taneous processes of divergence and convergence. The origin (...) of life through autocatalytic closure, and the origin of an interconnected worldview through conceptual closure, induced phase transitions in the degree to which informa- tion, and thus consciousness, is locally amplified. Divergence and convergence of cognitive information may involve phenomena observed in light e.g. focusing, interference, and resonance. By making information flow inward- biased, clo- sure shields us from external consciousness; thus the paucity of consciousness may be an illusion. (shrink)

Transpersonal psychology first emerged as an academic discipline in the 1960s and has subsequently broadened into a range of transpersonal studies. Jorge Ferrer (2002) has called for a 'revisioning' of transpersonal theory, dethroning inner experience from its dominant role in defining and validating spiritual reality. In the current paradigm he detects a lingering Cartesianism, which subtly entrenches the very subject-object divide that transpersonalists seek to overcome. This paper outlines the development and current shape of the transpersonal movement, compares Ferrer's epistemology (...) with the heterophenomenology of Daniel Dennett, and speculates on the integration of the latter into transpersonal theory. (shrink)

_Behavioral and Brain Sciences_ , 15, 183-247, 1992. Reprinted in _The Philosopher's Annual_ , Grim, Mar and Williams, eds., vol. XV-1992, 1994, pp. 23-68; Noel Sheehy and Tony Chapman, eds., _Cognitive Science_ , Vol. I, Elgar, 1995, pp.210-274.

Propositions such as are paradoxical, in that even though they can be true, they cannot be truly asserted or believed. This is Moore’s paradox. Sydney Shoemaker has recently ar- gued that the paradox arises from a constitutive relation that holds between first- and second-order beliefs. This paper explores this approach to the paradox. Although Shoemaker’s own account of the paradox is rejected, a different account along similar lines is endorsed. At the core of the endorsed account is the claim that (...) conscious beliefs are always partly about themselves; it will be shown to follow from this that conscious beliefs in Moorean propositions are self-contradictory. (shrink)

Carruthers proposes that for a mental state to be conscious , it must be present in a.

Because metacognition consists in our having mental access to our cognitive states and mental states are conscious only when we are conscious of them in some suitable way, metacognition and consciousness shed important theoretical light on one another. Thus, our having metacognitive access to information carried by states that are not conscious helps con?rm the hypothesis that a mental state.

Few contemporary researchers in psychology, philosophy, and the cognitive sciences have any doubt about whether mental phenomena occur without being conscious. There is extensive and convincing clinical and experimental evidence for the existence of thoughts, desires, and related mental states that aren’t conscious. We characterize thoughts, desires, intentions, expectations, hopes, and many other mental states in terms of the things they are about and, more fully, in terms of their content, as captured by a sentence nominalization, such as a clause (...) beginning with the word ‘that’. The philosophical literature follows Franz Brentano’s adaptation of Thomist terminology in referring to all such states as intentional states. But there is another type of mental phenomena, which lack intentionality and whose mental nature consists instead of some qualitative feature. These states include bodily sensations, such as aches and pains, and perceptual states, such as visual sensations of color and tactile sensations of heat and cold. And these states all exhibit some mental quality or another, such as the mental quality distinctive of pain or the mental quality of red or blue.1 And even theorists who acknowledge that intentional states can and do occur without being conscious have sometimes insisted that qualitative states cannot. There is, according to these theorists, nothing to a state’s being qualitative or exhibiting some mental quality unless that state is conscious – unless it is, as we might metaphorically say, “lighted up”. It’s striking that Freud himself seems to have adopted this double standard toward the two types of mental state. In his metapsychological paper, “The Unconscious”, for example, he writes that “all the categories which we employ to describe conscious mental acts, such as ideas, purposes, resolutions, and so forth, can be applied to [unconscious mental occurrences]” (Freud 1915e, p. 168). But he seems here to have in.. (shrink)

This article replies to the main objections raised by the commentators on Carruthers . It discusses the question of what evidence is relevant to the assessment of dispositional higher-order thought theory; it explains how the actual properties of phenomenal consciousness can be dispositionally constituted; it discusses the case of pains and other bodily sensations in non-human animals and young children; it sketches the case for preferring higher-order to first-order theories of phenomenal consciousness; and it replies to some miscellaneous points and (...) objections. (shrink)

My topic in this chapter is whether phenomenal consciousness can be given a reductive natural explanation. I shall first say something about phenomenal—as opposed to other forms of—consciousness, and highlight what needs explaining. I shall then turn to issues concerning explanation in general, and the explanation of phenomenal consciousness in particular.

The identity of conscious states and brain states must remain a mystery until we find a way of characterising both sides of the equation in terms that have the same ‘dimensions’. In this paper I stress the need for ‘dual currency concepts’ that not only are but can be seen to be as appropriate for talking about, say, the experience of pain as for talking about the corresponding working of the brain. In the light of evolutionary theory I make a (...) radically new proposal for what the common dimension is, centred on the idea of ‘authorship’. (shrink)

The mind body problem is a continuing issue in philosophy. No surveys known to us have been conducted about the actual preferences of, for example, psychology students for particular preconceptions about the mind body relation. These preconceptions may have different practical implications for decisions concerning the object and method of research, the choice of explanatory device for psychological and other research data and for the approach of professionals in practice. A questionnaire comprising ten different preconceptions about the mind body relation (...) and other items was returned by 209 German students of various disciplines and by a second sample of 233 first year psychology students. Identity theory, interactionism and complementarity were preferred most. The students clearly believed that the preference for certain preconceptions has important practical implications. There were no differences between the students of different disciplines in the choice of preferred preconceptions about the mind body relation or in the view that these preconceptions are of practical importance. (shrink)

Journal of Mind and Behavior 28 no. 2 , pp. 135-156. The self-prompting theory of consciousness holds that conscious perceptual experience occurs when non-routine perceptual data prompt the activation of a plan in an executive control system that monitors perceptual input. On the other hand, routine, non-conscious perception merely provides data about the world, which indicatively describes the world correctly or incorrectly. Perceptual experience instead involves data that are about the perceiver, not the world. Their function is that of imperatively (...) prompting the perceiver herself to do something (hence. (shrink)

The notion of the cyborg has exercised the popular imagination for almost two hundred years. In very general terms the idea that a living entity can be a hybrid of both organic matter and mechanical parts, and for all intents and purposes be seamlessly functional and self-regulating, was prefigured in literary works such as Shelly
s Frankenstein and Samuel Butler
s Erewhon . This notion of hybridism has been a staple theme of 20th century science fiction writing, television programmes and the cinema. (...) For the most part, these works trade on a deep sense of unease we have about our personal identity – how could some non-organic matter to which I have so little conscious access count as a bona fide part of me? Cognitive scientist and philosopher, Andy Clark, picks up this general theme and presents an empirical and philosophical case for the following inextricably linked theses. (shrink)

Frank Jackson’s knowledge argument is a very influential piece of reasoning that seeks to show that colour experiences constitute an insoluble problem for science. This argument is based on a thought experiment concerning Mary. She is a vision scientist who has complete scientific knowledge of colours and colour vision but has never had colour experiences. According to Jackson, upon seeing coloured objects, Mary acquires new knowledge that escapes her complete scientific knowledge. He concludes that there are facts concerning colour experiences (...) that scientific knowledge can neither describe nor explain. Specifically, these facts involve the occurrence of certain non-physical properties of experiences that he calls qualia. The present research considers whether a plausible formulation of the hypothesis that science can accommodate colour experiences is threatened by a version of the knowledge argument. The specific formulation of this problem has two motivations. Firstly, before investigating whether the knowledge argument raises a problem for the claim that science can account for colour experiences, we need a plausible formulation of this claim. I argue that the idea that science can accommodate colour experiences can be formulated as the modest reductionism hypothesis. Roughly speaking, this is the hypothesis that a science that can be explanatory interfaced with current physics of ordinary matter can account for conscious experiences. Secondly, an unintelligible premise figures in Jackson’s version the knowledge argument. Namely, it is assumed that Mary possesses a complete scientific knowledge. Nevertheless, the type of strategy involved in Jackson’s argument can be used to target modest reductionism. By considering contemporary psychophysics and neuroscience, I characterise Mary’s scientific knowledge. First, this characterisation is intelligible. In fact, it is elaborated on the basis of descriptions and explanations of colour experiences involved in current physics and neuroscience. Second, a supporter of modest reductionism can assume that the scientific knowledge ascribed to Mary might account for colour experiences. The main conclusion of the present research is that our version of the knowledge argument fails to threaten the modest reductionism hypothesis. In fact, I endorse what can be called the “two ways of thinking” reply to the knowledge argument. According to this response, the knowledge argument shows that there are different ways of thinking about colour experiences. One way of thinking is provided by scientific knowledge. The other way of thinking is provided by our ordinary conception of colour experiences. However, the existence of these two ways of thinking does not imply the existence of facts and properties that escape scientific knowledge. It might be the case that the ordinary way of thinking about colour experience concerns facts and properties described and explained by science. The principal conclusion of the research results from two investigations. The first line of research aims to reveal and evaluate the implicit assumptions that figure in the knowledge argument. The main body of the research is dedicated to this task. The principal result of this investigation is that the knowledge argument must rely on an account of introspective knowledge of colour experiences. I argue that an inferential model of introspection provides such account. On this model, Mary’s capacity to hold beliefs about her colour experiences when she sees coloured objects requires her mastery of colour concepts. The second main investigation seeks to justify the two ways of thinking strategy. As many opponents and supporters have recently started to realise, this strategy might be charged with being ad hoc. I offer a distinctive justification of this reply to the knowledge argument. Assuming the account of introspection mentioned above, the existence of visual recognitional colour concepts might justify this strategy. A person possesses these concepts when she is able to determine the colours of objects simply by having visual experiences. (shrink)

This paper is trying to show that it is not possible to use the Knowledge argument as independent evidence for the form of non-reductionism the Modal argument argues for. To show this, Jackson's famous 'Mary' thought experiment is imagined in a zombie world. This leads to the result that there are many problems in the Mary experiment, which cannot have anything to do with phenomenal Qualia, because the Zombie-Mary would encounter them as well, and once all these problems are accounted (...) for, it is no longer clear whether a Zombie-Mary is conceivable at all. Finally, an alternative explanation for the strong non-reductive intuitions of the Mary experiment is discussed. (shrink)

In this paper I challenge the core of David Chalmers' argument against materialism-the claim that "there is a logically possible world physically identical to ours, in which the positive facts about consciousness do not hold." First, I analyze the move from conceivability to logical possibility. Following George Seddon, I consider the case of a floating iron bar and argue that even this seemingly conceivable event has implicit logical contradictions in its description. I then show that the distinctions Chalmers employs between (...) primary and secondary intensions, and a priori and a posteriori entailment, break down upon close examination-with iron bars and with consciousness it is impossible to know where primary intensions end and secondary intensions begin. I extend this analysis of logical possibility to the famous zombie thought experiment and conclude not that a zombie world is logically impossible, but rather that, at present, the question is open. Finally, I show how a similar line of argument may be used to undermine the "Mary the color scientist" thought experiment as well. (shrink)