Online research in philosophy

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.

The “explanatory gap” is proposed to be the “hard problem” of consciousness research and has generated a great deal of recent debate. Arguments brought forward to reveal this gap include the conceivability of zombies or the “super-neuroscientist” Mary. These are supposed to show that the facts of consciousness are not a priori entailed by the microphysical facts. Similar arguments were already proposed by emergence theories in the context of the debate between mechanism and vitalism. According to synchronic emergentism, the property of a system is emergent, when it cannot - in principle - be deduced from a complete description of the system’s components. Here, I argue that apart from phenomenal properties there are many other properties that, even though they are clearly physical, are not reductively explainable either. The explanatory gap of consciousness is therefore only a part of a much more general problem.

This paper is an attempt to understand the content of, and motivation for, a popular form of physicalism, which I call ‘non-reductive physicalism’. Non-reductive physicalism claims although the mind is physical (in some sense), mental properties are nonetheless not identical to (or reducible to) physical properties. This suggests that mental properties are, in earlier terminology, ‘emergent properties’ of physical entities. Yet many non-reductive physicalists have denied this. In what follows, I examine their denial, and I argue that on a plausible understanding of what ‘emergent’ means, the denial is indefensible: non-reductive physicalism is committed to mental properties being emergent properties. It follows that the problems for emergentism—especially the problems of mental causation—are also problems for non-reductive physicalism, and they are problems for the same reason.

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 physical/nonphysical 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.

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 physical/nonphysical 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.

According to the self-representational theory of consciousness – self- representationalism for short – a mental state is phenomenally conscious when, and only when, it represents itself in the right way. In this paper, I consider how self- representationalism might address the alleged explanatory gap between phenomenal consciousness and physical properties. I open with a presentation of self- representationalism and the case for it (§1). I then present what I take to be the most promising self-representational approach to the explanatory gap (§2). That approach is threatened, however, by an objection to self-representationalism, due to Levine, which I call the just more representation objection (§3). I close with a discussion of how the self-representationalist might approach the objection (§4).

Some people believe that there is an “explanatory gap” between the facts of physics and certain other facts about the world—for example, facts about consciousness. The gap is presented as a challenge to any thoroughgoing naturalism or physicalism. We believe that advocates of the explanatory gap have some reasonable expectations that cannot be merely dismissed. We also believe that naturalistic thinkers have the resources to close the explanatory gap, but that they have not adequately explained how and why these resources work. In this paper we isolate the legitimate explanatory demands in the gap reasoning, as it is defended by Chalmers and Jackson (2001). We then argue that these demands can be met. Our solution involves a novel proposal for understanding the relationship between theories, explanations, and scientific identities.

Some people believe that there is an “explanatory gap” between the facts of physics and certain other facts about the world—for example, facts about consciousness. The gap is presented as a challenge to any thoroughgoing naturalism or physicalism. We believe that advocates of the explanatory gap have some reasonable expectations that cannot be merely dismissed. We also believe that naturalistic thinkers have the resources to close the explanatory gap, but that they have not adequately explained how and why these resources work. In this paper we isolate the legitimate explanatory demands in the gap reasoning, as it is defended by Chalmers and Jackson (2001). We then argue that these demands can be met. Our solution involves a novel proposal for understanding the relationship between theories, explanations, and scientific identities.

I argue that the explanatory gap is generated by factors consistent with the view that qualia are physical properties. I begin by considering the most plausible current approach to this issue based on recent work by Valerie Hardcastle and Clyde Hardin. Although their account of the source of the explanatory gap and our potential to close it is attractive, I argue that it is too speculative and philosophically problematic. I then argue that the explanatory gap should not concern physicalists because it makes excessive demands on physical theory.

This paper examines a paradigm case of allegedly successful reductive explanation, viz. the explanation of the fact that water boils at 100°C based on facts about H2O. The case figures prominently in Joseph Levine’s explanatory gap argument against physicalism. The paper studies the way the argument evolved in the writings of Levine, focusing especially on the question how the reductive explanation of boiling water figures in the argument. It will turn out that there are two versions of the explanatory gap argument to be found in Levine’s writings. The earlier version relies heavily on conceptual analysis and construes reductive explanation as a process of deduction. The later version makes do without conceptual analysis and understands reductive explanations as based on theoretic reductions that are justified by explanatory power. Along the way will be shown that the bridge principles — which are being neglected in the explanatory gap literature — play a crucial role in the explanatory gap argument.