Online research in philosophy

ne ’ s a r gume nt s i n de a l i ng wi t h e ve n a s hi ghl y i nt r a c t a bl e an issue as the mystery of consciousness. The mind-body problem in a contemporary guise is rooted in two prima facie plausible but incompatible propositions that philosophers have reached: (1) Some form of materialism or physicalism is true. (2) Phenomenal consciousness, raw feel, or qualia cannot be explained physicalistically. The traditional strategy for solving the problem is simply to reject one or the other of these propositions. Thus some philosophers reject (1) and become dualists accordingly, and others reject (2) and become materialists accordingly. Levine, however, ventures to accept both of them at the same time. That is, while he defends materialism he also believes that we can never make a priori derivations from physical facts to phenomenal facts. Chapter 1 of the book is devoted to establishing (1). In order to define his materialism Levine reflects nested dilemmas that materialism in general confronts. The di l e mma s go a s f ol l ows..

The majority of contemporary philosophers of mind are physicalists. The majority of physicalists, however, are non-reductive physicalists. As nonreductive physicalists, these philosophers hold that a system's mental properties are different from a system's physical properties, that is, they hold that the sum total of mental facts about some system is a different set of facts than the sum total of physical facts about the same system. As physicalists, however, these nonreductivists hold that mental facts are nonetheless determined by physical facts, that is, they subscribe to the supervenience thesis, i.e., the thesis that no mental differences can obtain without physical differences obtaining. In this paper I take up the issue of how best to understand the notion of supervenience, especially in the light of recent advances in the neurosciences.

In recent years there has been a resurgence of interest in property dualism—the view that some mental properties are neither identical with, nor strongly supervenient on, physical properties. One of the principal objections to this view is that, according to natural science, the physical world is a causally closed system. So if mental properties are really distinct from physical properties, then it would seem that mental properties never really cause anything that happens in the physical world. Thus, dualism threatens to lead inexorably to epiphenomenalism. In this paper, I will argue that the only way for a property dualist to avoid epiphenomenalism is to deny that the human body is strictly identical with the sum of its microphysical parts. I will go on to argue that the only way to sustain such anti-reductionism about the human body is to embrace some sort of substance-hylomorphism.

I take myself to be a physicalist. I hold that all facts, including such prima facie non-physical facts as mental and biological facts, metaphysically supervene on the physical facts. However, I do not have any views about the relationship between macroscopic and microscopic facts. I am neutral on such questions as whether big things are always made of small things. Recently I have become worried about this combination of views. This is because many other philosophers seem to think of physicalism as some kind of commitment to the primacy of the microscopic. In their view, physicalism doesn’t just say that everything is physical. It also says that everything is microscopically determined. Here are some representative quotations.

The aim of this book is to defend ‘explanatory gap’, Levine’s own influential notion in the philosophical studies of phenomenal consciousness. The entire book proves how clear and systematic are Levine’s arguments in dealing with even as highly intractable an issue as the mystery of consciousness. The mind-body problem in a contemporary guise is rooted in two prima facie plausible but incompatible propositions that philosophers have reached: (1) Some form of materialism or physicalism is true. (2) Phenomenal consciousness, raw feel, or qualia cannot be explained physicalistically. The traditional strategy for solving the problem is simply to reject one or the other of these propositions. Thus some philosophers reject (1) and become dualists accordingly, and others reject (2) and become materialists accordingly. Levine, however, ventures to accept both of them at the same time. That is, while he defends materialism he also believes that we can never make a priori derivations from physical facts to phenomenal facts.

We wish to defend Jonathan Westphal's view that colour is complex against a recent ‘phenomenological’ criticism of Eric Rubenstein. There is often thought to be a conflict between two kinds of determinants of colour, physical and phenomenal. On the one hand there are the complex physical facts about colour, such as the determination of a surface colour by an absorption spectrum. There is also, however, the fact that the apparently simple phenomenological quality of what is seen is a function of the physiological and psychological state of the viewing subject. Should the physical trump the phenomenal, or is it the other way round? Much of the phenomenal variation of colour, however, is explained by physical facts. There is a physics and a psychophysics of colour. Colours appear, to the colour scientists at least, to be in some sense objective, a sense not explained by the view that they are purely phenomenal. Taking physics and psychophysics into account will mean rejecting the claim that the content of what our concepts of colours are concepts of is exhausted by the purely phenomenal, or that we can determine these concepts simply by gazing at a colour. Taking account of physics will lead, as Westphal argued, instead to a view about white and the other colour terms like Putnam's account of gold. Necessary truths about colours cannot be explained without reference to the logic of the compossibility of what is given in reflection and absorption spectra, the analogue of H2O.

We imagine Zombies as beings identical to us with respect to all physical and behavioural facts but different with respect to phenomenal facts. For example, zombies might say, just like us, ‘this grapefruit is really sour’ or ‘my left knee hurts’, but, unlike us, they have no phenomenal experiences corresponding to these utterances or to the relevant physical states. The idea of zombies has been used to construct the following argument against the physicalist approach to consciousness.

In a now famous thought experiment, Frank jackson asked us t0 imagine an omniscient scientist, Mary, who is coniincd in a black-and-white room and then released into the world 0f color (jackson 1982; jackson 1986; cf. Braddon—Mitch<-:11 and Jackson 1996). Assuming that she is omniscicnt in respect of all physical facts—roughiy, all the facts available to physics and all the facts that they in turn Hx or determine-physicalism would suggest that there is no new fact Mary can discover after emancipation; physicalism holds that all facts are physical in the relevant sense (for a fuller statement scc Pettit 1993; jackson 1998). Yet we cannot help but feel that coming out of that room would be an occasion of dramatic enlightenment and, in particular, an occasion for learning facts to do with how red or yellow or blue 100ks or, as it is usually said, with what it is like t0 sec red or yellow or blue. Many in the black-and—whit<—: room knew all the physical facts about the world, where these may be taken to include three sorts of color facts: objcctual facts, as to what surface colors different objects have, assuming as I shall do throughout—that colors are properties of objects; intentional facts, as to which colors different objects 0r apparent objects are represented as having in the subjc-:ct’s experience, rightly or wrongly; and nonintentional facts, about what such color experiences are like in their effects on subiccts—wh<—:ther they are comforting, or arousing, or whatever. But, according to the argument, Mary didn’t know how any color looks or, equivalently, what color experience is like in itself, not just in its effects O1'1 subjects. This particular nonintentional fact about the quality of color c-zxpc-2ri<—:ncc-—this phenomenal fact, as it is often describcd—she did not..

Property dualism is enjoying a slight resurgence in popularity, these days; substance dualism, not so much. But it is not as easy as one might think to be a property dualist and a substance materialist. The reasons for being a property dualist support the idea that some phenomenal properties (or qualia) are as fundamental as the most basic physical properties; but what material objects could be the bearers of the qualia? If even some qualia require an adverbial construal (if they are modifications of the thing that is conscious because of them, not properties of something else to which the subject of consciousness is related), then the property dualist can be driven to speculative forms of materialism none of which, at this point, looks more likely to be true than the more modest versions of emergent dualism defended by contemporary substance dualists.

Case 1: Perhaps the phenomenal facts—facts about what it’s like to see red, or to taste freshly made pesto—do not supervene with metaphysical necessity on the physical facts and physical laws. This might be because the connections between the physical and the phenomenal are entirely unprincipled. Alternatively, it might be because whatever psychophysical laws do govern those connections are contingent. Either way, the claim is that there are metaphysically possible worlds that are just like the actual world in terms of what physical laws hold, and in terms of the distribution of physical properties, but which are phenomenally different from the actual world. In some such worlds, different phenomenal facts obtain. In other such worlds, no phenomenal properties are instantiated at all. Call the latter sort of world a ‘phenomenal zombie world’, or, for short, just a ‘zombie world’.