Online research in philosophy

It is a common conviction among philosophers who hold that phenomenal properties, qualia, are distinct from any cognitive, intentional, or functional properties, that it is possible to trace the neural correlates of these properties. The main purpose of this paper is to present a challenge to this view, and to show that if “non-cognitive” phenomenal properties exist at all, they lie beyond the reach of neuroscience. In the final section it will be suggested that they also lie beyond the reach of psychology, so that they may be said to lie beyond the reach of science.

Sydney Shoemaker offers an account of color perception that attempts to do justice, within a functionalist framework, to the commonsense view that colors are properties of ordinary objects, to the existence of qualia, and to the possibility of spectrum inversions. Shoemaker posits phenomenal properties as dispositional properties of colored objects that explain how there can be intersubjective variation in the experience of a particular color. I argue that his account does not in fact allow for the description of a spectrum inversion scenario, and that it cannot sustain a functionalist relationship between an object's color and its phenomenal properties. Functionalists must, however, come to terms with Shoemaker's recognition that intersubjective spectrum shifts are possible.

It is widely accepted that conscious experience has a physical basis. That is, the properties of experience (phenomenal properties, or qualia) systematically depend on physical properties according to some lawful relation. There are two key questions about this relation. The first concerns the strength of the laws: are they logically or metaphysically necessary, so that consciousness is nothing "over and above" the underlying physical process, or are they merely contingent laws like the law of gravity? This question about the strength of the psychophysical link is the basis for debates over physicalism and property dualism. The second question concerns the shape of the laws: precisely how do phenomenal properties depend on physical properties? What sort of physical properties enter into the laws' antecedents, for instance; consequently, what sort of physical systems can give rise to conscious experience? It is this second question that I address in this paper.

According to qualia-epiphenomenalism, phenomenal properties are causally inefficacious, they are metaphysically distinct from, and nomologically connected with certain physical properties. The present paper argues that the claim of causal inefficacy undermines any effort to establish the alleged nomological connection. Epiphenomenalists concede that variations of phenomenal properties in the absence of any variation of physical/functional properties are logically possible, however they deny that these variations are nomologically possible. But if such variations have neither causal nor functional consequences, there is no way to detect themanot only in scientific experiments, but also from the first-person perspective. Since neither third- nor first- person evidence can rule out the actual occurrence of such dissociations, the alleged nomological connection between phenomenal and physical properties cannot be established, in principle. As a consequence, the distinction between logical and nomological possibility breaks down and it cannot be ruled out that such dissociations occur in an unlimited number of cases.

The central attempt of this paper is to explain the underlying intuitions of Frank Jackson’s “Knowledge Argument” that the epistemic gap between phenomenal knowledge and physical knowledge points towards a corresponding ontological gap. The first step of my analysis is the claim that qualia are epistemically special because the acquisition of the phenomenal concept of a quale x requires the experience of x. Arguing what is so special about phenomenal concepts and pointing at the inherence-relation with the qualia they pick out, I give compelling reasons for the existence of ontologically distinct entities. Finally I conclude that phenomenal knowledge is caused by phenomenal properties and the instantiation of these properties is a specific phenomenal fact, which can not be mediated by any form of descriptive information. So it will be shown that phenomenal knowledge must count as the possession of very special information necessarily couched in subjective, phenomenal conceptions.

Phenomenal knowledge usually comes from experience. But it need not. For example, one could know what it’s like to see red without seeing red—indeed, without having any color experiences. Daniel Dennett (2007) and Pete Mandik (forthcoming) argue that this and related considerations undermine the knowledge argument against physicalism. If they are right, then this is not only a problem for anti‐physicalists. Their argument threatens to undermine any version of phenomenal realism—the view that there are phenomenal properties, or qualia, that are not conceptually reducible to physical or functional properties. I will argue that this threat is illusory. Explaining why will clarify what is and is not at issue in discussions of the knowledge argument and phenomenal realism. This will strengthen the case for physically and functionally irreducible qualia.

Representational theorists identify experiences’ phenomenal properties with their representational properties. Qualia theorists reject this identity, insisting that experiences’ phenomenal properties can come apart from and completely outrun their representational properties. Qualia theorists account for phenomenal properties in terms of “qualia,” intrinsic mental properties they allege experiences to instantiate. The debate between representational theorists and qualia theorists has focused on whether phenomenal properties really can come apart from and completely outrun representational properties. As a result, qualia theorists have failed (1) to explain how experiences owe their phenomenal properties to their instantiation of qualia and (2) to clarify the nature of subjects’ epistemic access to qualia. I survey qualia theorists’ options for dealing with each issue and find them all wanting.