David Rosenthal

Dualism is the view that mental phenomena are, in some respect, nonphysical. The best-known version is due to Descartes, and holds that the mind is a nonphysical substance. Descartes argued that, because minds have no spatial properties and physical reality is essentially extended in space, minds are wholly nonphysical. Every human being is accordingly a composite of two objects: a physical body, and a nonphysical object that is that human being's mind. On a weaker version of dualism, which contemporary thinkers find more acceptable, human beings are physical substances but have mental properties, and those properties aren't physical. This view is known as property dualism, or the dual-aspect theory

Theories of what it is for a mental state to be conscious must answer two questions. We must say how we're conscious of our conscious mental states. And we must explain why we seem to be conscious of them in a way that's immediate. Thomas Natsoulas distinguishes three strategies for explaining what it is for mental states to be conscious. I show that the differences among those strategies are due to the divergent answers they give to the foregoing questions. Natsoulas finds most promising the strategy that amounts to the higher-order-thought hypothesis that I've defended elsewhere. But he raises a difficulty for it, which he thinks probably can be met only by modifying that strategy. I argue that this is unnecessary. The difficulty is a special case of a general question, the answer to which is independent of any issues about consciousness. So it's no part of a theory of consciousness to address the problem, much less solve it. Moreover, the difficulty seems to have intuitive force only given the picture that underlies the other two explanatory strategies, which both Natsoulas and I reject

Striking experimental results by Benjamin Libet and colleagues have had an impor- tant impact on much recent discussion of consciousness. Some investigators have sought to replicate or extend Libet’s results (Haggard, 1999; Haggard & Eimer, 1999; Haggard, Newman, & Magno, 1999; Trevena & Miller, 2002), while others have focused on how to interpret those findings (e.g., Gomes, 1998, 1999, 2002; Pockett, 2002), which many have seen as conflicting with our commonsense picture of mental functioning

Moore’s paradox occurs with sentences, such as (1) It’s raining and I don’t think it’s raining. which are self-defeating in a way that prevents one from making an asser- tion with them.1 But Mark Crimmins has given us a case of a sentence that is syntactically just like (1) but is nonetheless assertible. Suppose I know somebody, and know or have excellent reason to believe that I know that very person under some other guise. I do not know what that other guise is, though I do know that I believe that the person I know under that other guise is an idiot.

I begin by considering Ned Block's widely accepted distinction between phenomenal and access consciousness. I argue that on Block's official characterization a mental state's being access conscious is not a way the state's being conscious in any intuitive sense; that if phenomenal consciousness itself corresponds to an intuitive way of a state's being conscious, it literally implies access consciousness; and that Block misconstrues the theoretical significance of the commonsense distinction. These considerations point to the view that mental states' being conscious consists in their being accompanied by occurrent, assertoric thoughts to the effect that one is in the state in question: what I have elsewhere called higher- order thoughts (HOTs). After outlining the model, I sketch theoretical advantages having to do with introspective consciousness, the relationship between consciousness and speech, and the metacognitive phenomenon known as feeling-of-knowing judgments. I conclude by showing that the HOT model does justice to phenomenal consciousness: Sensory states are not all conscious, and HOTS explain why there is something it is like to be in those which are.

Consciousness and Mind presents David Rosenthal's influential work on the nature of consciousness. Central to that work is Rosenthal's higher-order-thought theory of consciousness, according to which a sensation, thought, or other mental state is conscious if one has a higher-order thought that one is in that state. The first four essays develop various aspects of that theory. The next three essays present Rosenthal's homomorphism theory of mental qualities and qualitative consciousness, and show how that theory fits with and helps sustain the HOT theory. A crucial feature of homomorphism theory is that it individuates and taxonomizes mental qualities independently of the way we're conscious of them, and indeed independently of our being conscious of them at all. So the theory accommodates the qualitative character not only of conscious sensations and perceptions, but also of those which fall outside our stream of consciousness. Rosenthal argues that, because this account of mental qualities makes no appeal to consciousness, it enables us to dispel such traditional quandaries as the alleged conceivability of undetectable quality inversion, and to disarm various apparent obstacles to explaining qualitative consciousness and understanding its nature. Six further essays build on the HOT theory to explain various important features of consciousness, among them the complex connections that hold in humans between consciousness and speech, the self-interpretative aspect of consciousness, and the compelling sense we have that consciousness is unified. Two of the essays, one an extended treatment of homomorphism theory, appear here for the first time. There is also a substantive introduction, which draws out the connections between the essays and highlights their implications.

Edited in hypertext by Andrew Chrucky. Reprinted with the permission of Professor David Rosenthal. Editor's Note: Due to the limitation of current hypertext, the following conventions have been used. In general, if an expression has some mark over it, that mark is placed as a prefix to the expression. All Greek characters are rendered by their names. Subscripts are placed in parentheses as concatenated suffixes: thus, e.g., HO is the chemical formula for water. Sellars' dot quotes are expressed by bold periods

At the level of our platitudinous background knowledge about things, speech is the expression of thought. And understanding what such expressing involves is central to understanding the relation between thinking and speaking. Part of what it is for a speech act to express a mental state is that the speech act accurately captures the mental state and can convey to others what mental state it is. And for this to occur, the speech act at least must have propositional content that somehow reflects that of the mental state, and perhaps must have other such properties as well