Online research in philosophy

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.

This article compares the three frameworks for theories of consciousness that are taken most seriously by neuroscientists, the view that consciousness is a biological state of the brain, the global workspace perspective and an account in terms of higher order states. The comparison features the “explanatory gap” (Nagel, 1974; Levine, 1983) the fact that we have no idea why the neural basis of an experience is the neural basis of that experience rather than another experience or no experience at all. It is argued that the biological framework handles the explanatory gap better than the global workspace of higher order views. The article does not discuss quantum theories or “panpsychist” accounts according to which consciousness is a feature of the smallest particles of inorganic matter (Chalmers, 1996; Rosenberg, 2004). Nor does it discuss the “representationist” proposals (Tye, 2000; Byrne, 2001a) that are popular among philosophers but not neuroscientists.

Consciousness often presents itself as a problem for materialists because no matter which physical explanation we consider, there seems to remain something about conscious experience that hasn't been fully explained. This gives rise to an apparent explanatory gap. The explanatory gulf between the physical and the conscious is reflected in the broader population, in which dualistic intuitions abound. Drawing on recent empirical evidence, this essay presents a dual-process cognitive model of consciousness attribution. This dual-process model, we suggest, provides an important part of the explanation for why dualism is so attractive and the explanatory gap so vexing.

Contrary to certain rumours, the mind-body problem is alive and well. So argues Joseph Levine in Purple Haze: The Puzzle of Consciousness . The main argument is simple enough. Considerations of causal efficacy require us to accept that subjective experiential, or 'phenomenal', properties are realized in basic non-mental, probably physical properties. But no amount of knowledge of those physical properties will allow us conclusively to deduce facts about the existence and nature of phenomenal properties. This failure of deducibility constitutes an explanatory problem - an explanatory gap - but does not imply the existence of immaterial mental properties. Levine introduced this notion of the explanatory gap almost two decades ago. Purple Haze allows Levine to situate the explanatory gap in a broader philosophical context. He engages with those who hold that the explanatory gap is best understood as implying anti-materialist metaphysical conclusions. But he also seeks to distance himself from contemporary naturalistic philosophical theorizing about consciousness by arguing that reductive and eliminative theories of consciousness all fail. Levine's work is best seen as an attempt to firmly establish a definite status for the mind-body problem, i.e. that the mind-body problem is a real, substantive epistemological problem but emphatically not a metaphysical one. Because Levine's work is tightly focused upon contemporary Anglophone analytic philosophy of mind, there is little discussion of the broader conceptual background to the mind-body problem. My aim here is to place Levine's work in a broader conceptual context. In particular, I focus on the relationship between consciousness and intentionality in the belief that doing so will allow us better to understand and evaluate Levine's arguments and their place in contemporary theorizing about mentality and consciousness.

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).

Consciousness often presents itself as a problem for materialists because no matter which physical explanation we consider, there seems to remain something about conscious experience that hasn't been fully explained. This gives rise to an apparent explanatory gap. The explanatory gulf between the physical and the conscious is reflected in the broader population, in which dualistic intuitions abound. Drawing on recent empirical evidence, this essay presents a dual-process cognitive model of consciousness attribution. This dual-process model, we suggest, provides an important part of the explanation for why dualism is so attractive and the explanatory gap so vexing.

According to many philosophers, there is an explanatory gap between physical truths and phenomenal truths. Someone could know all the physical truths about the world, and in particular, all the physical information about the brain and the neurophysiology of vision, and still not know what it is like to see red (Jackson 1982, 1986). According to a similar example, someone could know all the physical truths about bats and still not know what it is like to be a bat (Nagel 1974). We can conceive of an individual that is physically identical to me, molecule per molecule, but does not have any phenomenally conscious state whatsoever (Chalmers 1996). Some philosophers have argued that the explanatory gap shows that we cannot explain consciousness in physical terms (Levine 2001), or even that phenomenal consciousness is not physical and therefore physicalism is false (Chalmers 1996, 2002).

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.

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.