In this paper I examine Chalmers and Jackson’s defence of the a priori entailment thesis, that is, the claim that microphysical truths a priori entail ordinary non-phenomenal truths such as ‘water covers 60% of the Earth surface’, which they use as a premise for an argument against the possibility of a reductive explanation of consciousness. Their argument relies on a certain view about the possession conditions of macroscopic concepts such as WATER, known as ascriptivism. In the paper I distinguish two (...) versions of ascriptivism: reductive versus non-reductive ascriptivism. According to reductive ascriptivism, competent users of a concept have the ability to infer truths involving such concept from lower-level truths, whereas according to non-reductive ascriptivism, all that is required in order to be a competent user of a concept is to be able to infer truths involving that concept from other truths, which need not be lower-level truths. I argue, first, that the a priori entailment thesis is committed to reductive ascriptivism, and secondly, that reductive ascriptivism is problematic because it trivializes the notion of a priori knowledge. Therefore, I conclude that Chalmers and Jackson have not presented a convincing case for the claim that microphysical truths entail ordinary non-phenomenal truths a priori, especially when we understand this claim in the sense that is relevant for their argument against the possibility of a reductive explanation of consciousness. (shrink)

To demonstrate that a fallacy is committed, Block needs to convince us of two things: first, that the concept of phenomenal consciousness is distinct from that of access consciousness, and second, that it picks out a different property from that of access consciousness. I raise doubt about both of these claims, suggesting that the concept of a phenomenal property is the concept of a property to which we have a special sort of access.

Consciousness is a mongrel concept: there are a number of very different "consciousnesses." Phenomenal consciousness is experience; the phenomenally conscious aspect of a state is what it is like to be in that state. The mark of access-consciousness, by contrast, is availability for use in reasoning and rationally guiding speech and action. These concepts are often partly or totally conflated, with bad results. This target article uses as an example a form of reasoning about a function of "consciousness" based on (...) the phenomenon of blindsight. Some information about stimuli in the blind field is represented in the brains of blindsight patients, as shown by their correct "guesses," but they cannot harness this information in the service of action, and this is said to show that a function of phenomenal consciousness is somehow to enable information represented in the brain to guide action. But stimuli in the blind field are BOTH access-unconscious and phenomenally unconscious. The fallacy is: an obvious function of the machinery of access-consciousness is illicitly transferred to phenomenal consciousness. (shrink)

David Chalmers' conceivability argument against physicalism relies on the entailment from a priori conceivability to metaphysical possibility. The a posteriori physicalist rejects this premise, but is consequently committed to psychophysical strong necessities. These don't fit into the Kripkean model of the necessary a posteriori, and they are therefore, according to Chalmers, problematic. But given semantic assumptions that are essential to the conceivability argument, there is reason to believe in microphysical strong necessities. This means that some of Chalmers' criticism is unwarranted, (...) and the rest equally afflicts the dualist. Moreover, given that these assumptions are independently plausible, there's a general case to be made for the existence of strong necessities outside the psychophysical domain. (shrink)

If phenomenal consciousness is distinct from the computationally based access-consciousness that controls overt behavior, how can I tell which things (other than myself) enjoy phenomenal consciousness? And if phenomenal consciousness 'plays no role in controlling overt behavior, how do human bodies come to write target articles arguing for the existence of phenomenal consciousness?

In Feeling of Knowing cases, subjects have a form of consciousness about the presence of a content (such as an item of information) without having access to it. If this phenomenon can be correctly interpreted as having to do with consciousness, then there would be a P-conscious mental experience which is dissociated from access.

This paper argues, not that physicalism is wrong, but that it is irrational. The paper defines standards of rationality, both metaphysical and epistemological, that physicalism necessarily inherits from science. Then it assesses physicalist efforts to naturalize consciousness in light of these. It concludes that physicalism allows its metaphysics to outrun its epistemology, in defiance of applicable standards, revealing a fundamental incoherence in the doctrine. The paper also briefly reviews other naturalization programs, to claim that physicalism, unlike the sciences, hasn’t proved (...) fruitful. (shrink)

Blocks distinction between “phenomenal feel” consciousness and “thought/cognition” consciousness is a cultural construction. Consciousness (and its “subspecies”) is not a natural kind. Some crosscultural data are presented to support this.

Block has attempted to reduce the confusion and controversy concerning the term “consciousness” by suggesting that there are two forms or types of consciousness, each of which has several characteristics or properties. This suggestion appears to further becloud the topic, however. Perhaps consciousness cannot be defined adequately and should not be considered as a topic that can be studied scientifically.

A number of philosophers think that, while we cannot explain how the mind is physical, we can know that it is physical, nonetheless. That is, they accept both the explanatory gap between the mental and the physical and ontological physicalism. I argue that this position is unstable. Among other things, I argue that once one accepts the explanatory gap, the main argument for ontological physicalism, the argument from causation, looses its force. For if one takes physicaVnonphysical causation and ontological physicalism (...) to be equally mysterious, as physicalists who accept the explanatory gap are inclined to do, there is little justification for accepting ontological physicalism rather than rejecting the causal closure of the physical. (shrink)

With some help from the commentators, a few adjustments to the characterizations of A-consciousness and P-consciousness can avoid some trivial cases of one without the other. But it still seems that the case for the existence of P without A is stronger than that for A without P. If indeed there can be P without A, but not A without P, this would be a remarkable result that would need explanation.

Additional experiments show that P-consciousness and A consciousness can be empirically dissociated for the theoretically so phisticated observer. Phenomenal consciousness can have several degrees that are indirectly measurable.

Block's cases of superblindsight, the pneumatic drill, and the Sperling experiments do not show that P-consciousness and Aconsciousness can come apart. On certain tendentious but not implausible construals of the concepts of P- and A-consciousness, they refer to the same psychological phenomenon.

In common sense consciousness has a fairly determinate content – the (single) way an experience feels, the (single) line of thought being consciously followed. The determinacy of the object may be achieved by linking Block's two concepts, so that as long as we hold on to the determinacy of content we are unable to separate P and A.

It is argued that there is no fallacy in the reasoning in the example of the thirsty blindsight subject, on one reconstruction of that reasoning. Neither the case of orgasm nor the case of a visual versus an auditory experience as of something overheard shows that phenomenal content is not representational.

Although not the main point of his target article, Block defends the view that perception and awareness of perception could be functions of different brain systems. I will argue that the available data do not support this view, and that Block's defense of the view rests on problematic eonstruals of the “executive system” and of the components of information-processing models.

A “fallacy” is something like the sense-datum fallacy, involving a logically invalid argument. A “conflation” is something like Block's conflation of the (alleged) raw feel of an experience with what it is like to have the experience. Trivially, a self is conscious of something only if it accesses it. Substantive issues concern the nature of the conscious self and the nature of access.

The superfunctionality claim is that phenomenal experiences are more than functional (objective, causal) relations. This is one of the most widely used but least attacked claims in the anti-physicalist literature on consciousness. Coupled with one form of structuralism, the view that science only explains functional relations, the superfunctionality claim entails that science will not explain phenomenal experience. The claim is therefore essential to many anti-physicalist arguments. I identify an open question argument for the superfunctionality claim that expresses an intuition deserving (...) of explanation. Using the experience of fear as an example, I show that this intuition cannot distinguish between whether conscious experiences are more than functional relations, or whether instead they are just very complex (including, constituted by very complex functional relations). I give reasons to suspect that the latter is more likely the case. This renders physicalism safe from the superfunctionality claim. This also provides a challenge to the proponents of the superfunctionality claim: they should explain why paradigmatically mysterious phenomenal experiences are correlated with extensive and complex physical correlates. (shrink)

The differences Block attempts to capture with his putative distinction between P-consciousness and A-consciousness are more directly and perspicuously handled in terms of differences in richness of content and degree of influence. Block's critiques, based on his misbegotten distinction, evaporate on closer inspection.

Dissociation thought experiments like Zombie and Inverted Spectrum cases play an essential role in the qualia debate. Critics have long since argued that these cases raise serious epistemic issues, undermining first person access to phenomenal states also in normal subjects. Proponents have denied this because, due to their phenomenal experience, normal subjects have epistemic abilities that Zombies don’t have. Here I will present a modified version of these thought experiments: Part-time Zombies and Part-time Inverts switch between normal and abnormal states (...) every now and then. Thus they provide insight into their epistemic situation showing that the mere possibility of Zombies and Inverts has consequences which undermine essential epistemic features of phenomenal properties even in normals. This line of reasoning will be corroborated by theoretical considerations on the epistemic requirements of phenomenal states. All this provides support for the “functional mapping hypothesis.” According to this hypothesis, any significant phenomenal difference can be mapped to a specific functional difference which is accessible from the third person perspective as well. (shrink)

Block's P-/A-consciousness distinction rules out P's involving a specific kind of cognitive access and commits him to a “strong” Pconsciousness. This not only confounds plausible research in the area but betrays an anosognosia about Wittgenstein's diagnosis about our philosophical “introspection” of mysterious inner processes.

I criticize Block's examples of P-consciousness and A-consciousness for being flawed and the notion of A-consciousness for not being a notion of consciousness at all. I argue that an empirically important distinction can be made between behavior that is supported by an underlying conscious experience and behavior that is brought about by nonconscious action-control mechanisms. This distinction is different from that made by Block.

Block seems to propose untested answers to empirical questions. Whether consciousness is a “mongrel problem,” rather than a single core fact with many facets, is an empirical issue. Likewise, the intimate relationship between personal consciousness and global access functions cannot be decided pretheoretically. This point is demonstrated by the reader's private experience of foveal versus parafoveal vision, and for conscious versus unconscious representation of the many meanings of common words.

The information processing that constitutes accessconsciousness is not sufficient to make a representational state conscious in any sense. Standard examples of computation without consciousness undermine A-consciousness, and Block's cases seem to derive their plausibility from a lurking phenomenal awareness. That is, people and other minded systems seem to have access-consciousness only insofar as the state accessed is a phenomenal one, or the state resulting from access is phenomenal, or both.

The aim of this paper is to determine the plausibility of Robert Kirk’s strict implication thesis as an explication of physicalism and its relation to Jackson and Chalmer’s notion of application conditionals, to the notion of global supervenience and to a posteriori identities. It is argued that the strict implication thesis is subject to the same objection that affects the notion of global supervenience. Furthermore, reference to an idealised physics in the formulation of strict implication threatens to make the thesis (...) vacuous. Third, Kirk’s claim that the strict implication thesis does not entail reduction of the mental to the physical (excluding phenomenal properties) is untenable if a functional model of reduction is preferred over Nagel’s classical model. Finally, Kirk’s claim that the physical facts entail in an a priori way the fact that certain brain states feel somehow seems to be unfounded. (shrink)

Two arguments are famously held to support the conclusion that consciousness cannot be explained in purely physical or functional terms – hence, that physicalism is false: the modal argument and the knowledge argument. While anti‐physicalists appeal to both arguments, this paper argues there is a methodological incoherence in jointly maintaining them: the modal argument supports the possibility of zombies; but the possibility of zombies undercuts the knowledge argument. At best, this leaves anti‐physicalists in a considerably weakened rhetorical position. At worst, (...) it shows that commonsense intuitions on which anti‐physicalists rely mislead us about the true nature of conscious experience. (shrink)

Richard Koch1 became known in the 1920s with works on basic medical theory. Among these publications, the character of medical action and its status within the theory of science was presented as the most important theme. While science is inherently driven by the pursuit of knowledge for its own sake, medicine pursues the practical purpose of helping the sick. Therefore, medicine must be seen as an active relationship between a helping and a suffering person. While elucidating this relationship, Koch discusses (...) the fundamental elements of medicine found in natural philosophy and the relationship of medicine to its own history. One of his aims is to unite natural history and the history of ideas without reducing intellectual processes to biological ones. Koch considers free will as something intuitively certain. It must serve as an axiom which will capture human as well as non-human reality. Based on the fact that human free will, considered a psychic quality, evolved out of inanimate matter, Koch grants matter (proto-) psychic qualities. They are evoked through specific constellations of matter. – With regard to history, Koch rejects the notion of constant progress. The history of medicine has provided insights that cannot be surpassed but can be obscured. Historical self-contemplation serves as a means for avoiding any deviations which may prevent medicine from fulfiling its ultimate purpose. Koch connects nature and history through the concept of a unity between natural history and the historical development of medicine. Medicine is considered an especially complex development of a purposive reaction to harmful stimuli, a reaction which can already be encountered in unicellular organisms. Without intending to reduce historical and mental processes to biological ones, Koch sets for himself the aim of gathering different phenomena and presenting them in one encapsulating unity. (shrink)

In response to the objection that his “access-consciousness” is not really consciousness but a matter of the availability of certain information for certain kinds of processing, Block will probably have to argue that consciousness in a more basic, familiar, traditional sense is an essential component of any instance of access-consciousness and thus justifies the name.

This commentary offers two criticisms of Block's account of phenomenal consciousness and a brief sketch of a rival account. The negative points are that monitoring consciousness also involves the possession of certain states and that phenomenal consciousness inevitably involves some sort of monitoring. My positive suggestion is that “phenomenal consciousness” may refer to our ability to monitor the rich but preconceptual states that retain perceptual information for complex processing.

A-consciousness may be regarded as the visibility of information that is the output of a process within a community of other processes. The most prominent function of “public” dissemination of information is giving access to it to processes whose relevance is not clear at the moment of dissemination. The function of P-consciousness may be outside the realm of cognition.

Should we distinguish between access and phenomenal consciousness? Block says yes and that various pathologies of consciousness support and clarify the distinction. The commentary charge that the distinction is neither supported nor clarified by the clinical data. It recommends an alternative reading of the data and urges Block to clarify the distinction.

Although information-processing theories cannot provide a full explanatory account of P-consciousness, there is less conflation and confusion in cognitive psychology than Block suspects. Some of the reasoning that Block criticises can be interpreted plausibly in the light of a folk psychological view of the relation between P-consciousness and A-consciousness.

Some cases of prosopagnosia involve a highly circumscribed loss of A-consciousness. When seen in this way they offer further support for the arguments made in Block's target article.

Block contends that the concept of consciousness is a mongrel concept and that researchers go astray by conflating different notions of “consciousness.” This is certainly true. In fact, it is truer than Block acknowledges, because his own notion of P-consciousness runs together two, or arguably three, quite different and separable features of a sensory state.

Basically agreeing with Block regarding the need for a distinction between P- and A-consciousness, I characterize the problem somewhat diflerently, relating it more directly to the explanatory gap. I also speculate on the relation between the two forms of consciousness, arguing that some notion of access is essentially involved in phenomenal experience.

Block's notion of P-consciousness catches too much in its net. He would do better to exclude all states that do not have a sensory component. I question what he says about my work with the “blind” monkey, Helen.

One can share Block's aim of distinguishing “phenomenal” experience from cognitive function and agree with much in his views, yet hold that the inclusion of representational content within phenomenal content, if only in certain spatial cases, obscures this distinction. It may also exclude some modular theories, although it is interestingly suggestive of what may be the limits of the phenomenal penetration of the representational mind.

Propositions as to the nature of consciousness, based on disorders of perception that result from brain damage, and taking insufficient account of the numerous ways in which normal subjects may deviate from that “usual” sequence of events (input → subjective awareness → output) risk increasing rather than diminishing any existing confusion about the function of consciousness.

Block's distinction between phenomenal and access consciousness is accepted, and it is agreed that one may be found without the other, but his account of the distinction is challenged. Phenomenal consciousness is perceptual consciousness, and it is a matter of gaining information of a detailed, nonverbal sort about the subject's body and environment. Access consciousness is good, old-fashioned introspection.