Michael Silberstein Converging on Emergence Consciousness, Causation and Explanation1 I will argue that emergence is an empirically plausible and unique philosophical/ scientific framework for bridging the ontological gap and the explanatory gap with respect to phenomenal consciousness. On my view the ontological gap is the gap between fundamental ingredients/parts of reality that are not conscious (such as particles and fields) and beings/wholes (such as ourselves) that are conscious. The explanatory gap is the current lack of a philosophical/scientific theory that explains how non-conscious parts can become conscious wholes. Both gaps are of course conceptual as well as empirical in nature. Section I will be devoted to these issues as well as providing other general criteria for an account of con- sciousness. In section II, different types of emergence will be defined in the con- text of a more general taxonomy of reduction and emergence. Emergentism about consciousness becomes much more plausible when we see that the ancient ‘atom- ism’ (i.e., mereological and nomological supervenience) that drives physicalism on one end, and fundamental property dualism on the other, is probably false. Backing up this claim will be the primary burden of section III. In section IV I will conjecture that phenomenal consciousness is mereologically and perhaps nomologically emergent from neurochemical/ quantum processes, just as many other properties are so emergent. In section V I defend my view of emergence against the objections that: (1) it cannot bridge the explanatory/ontological gap between matter and consciousness and (2) it cannot account for the causal effi- cacy of consciousness in itself. Finally, in section VI, there is speculation about where all of this might take us in the future. [1] I would like to thank three anonymous referees at JCS and Anthony Freeman for their helpful comments. I would like to give a special thanks to Robert Bishop and Harald Atmanspacher for their copious and insightful comments and suggestions. Journal of Consciousness Studies, 8, No. 9–10, 2001, pp. 61–98 Copyright (c) Imprint Academic 2011 For personal use only -- not for reproduction 62 M. SILBERSTEIN I: Introduction — Criteria for a Philosophical Account of Phenomenal Consciousness 1. Defining consciousness This section provides a yardstick for evaluating my emergentist account in partic- ular as well as competing accounts in general. I wish to provide a philosophical account of phenomenal consciousness (hereafter ‘consciousness’) that will help lay the foundation for a scientific account of consciousness. Indeed, ideally I think a philosophical account of consciousness should provide a framework for solving the empirical problem of how and why brains are conscious. Specifically, by consciousness I mean: the experience of being a subject (subjectivity) who experiences qualitative states such as seeing red or feeling pain (so-called qualia). Furthermore, it must be explained why/how conscious experience is unified or bound across short temporal spans such that we have simultaneous awareness of diverse features of any conscious state — diverse features that are apparently processed in diverse areas of the brain. I take it as an important open question as to whether or not the notion of qualitative states makes any sense in the absence of a subject. I don’t know if it is possible for an object (such as the brain) to merely instantiate rather than experience qua subject qualitative states, but I am doubtful. At any rate, sensory experience, memory, explicit cognition, dreams, emotions as we know them all count as consciousness by my definition. Though to be sure, conscious states are otherwise heterogeneous in phenomenal kind and in functional/neural realization. 2. What a theory of consciousness should do I want my philosophical account of consciousness to answer the following questions: (1) How is it conceivable/possible that consciousness arises from fundamen- tal elements (such as particles and fields) that are not themselves conscious? Not just physicalism, but any account of consciousness (including panpsychism/ panexperientialism for example) that does not posit fully conscious experiencing subjects as fundamental elements of reality (let us call this view full-blooded idealism) is going to have to face this question. In my view, to focus on the ontological/explanatory gap between ‘matter and mind’ creates more confusion than clarity because of the definitional problems involved with both concepts. For example, if we define matter as being inherently non-conscious and we define mind as being essentially conscious then we quickly find ourselves in an inescap- able morass, where we are forced into accepting extreme positions or crazy consequences. However for those of us who assume that full-blooded idealism is false (if only for the sake of discussion: after all if full-blooded idealism is true then there are no gaps whatsoever), there is an inescapable ontological/explanatory gap between the fundamental elements of reality (whatever they may be) that happen to be non-conscious and fully conscious experiencing subjects such as ourselves. This gap can only be fully bridged by a successful scientific account of how that which is not conscious becomes fully conscious. Copyright (c) Imprint Academic 2011 For personal use only -- not for reproduction CONVERGING ON EMERGENCE 63 The latter ontological/explanatory gap tables the age-old philosophical ques- tion about the ultimate ontic status of the world in general or of consciousness in particular: is the world or consciousness essentially physical, mental, functional or neutral in nature? Though I cannot defend my view fully in this article, I contend that the age-old philosophical question about the ultimate nature of mind, while perhaps meaningful, is irresolvable by either a priori or empirical means. More importantly, trying to answer this age-old philosophical question does nothing to help bridge the ontological/explanatory gap between the fundamental elements of reality that happen to be non-conscious and fully conscious experi- encing subjects such as ourselves. Philosophical accounts of consciousness such as materialism, physicalism, functionalism, panpsychism, etc., might provide answers to the age-old philosophical question about the nature of consciousness, but they do very little to help bridge the explanatory gap in question, or so I will argue as we go along. However there is no question that while bridging the explanatory gap in ques- tion requires a scientific explanation, that scientific project, like all of science, is inextricably bound with philosophy. On my view science is continuous with phi- losophy in a number of ways including the obvious historical/causal dimension. First, the scientific method itself and the very practice of science makes the meta- physical assumption that the world is orderly or lawful so as to be induction friendly. The practice of science also presupposes that its methods and our cogni- tive abilities are up to the task of revealing the deeper truths of the world. Second, any particular scientific theory just is an ontological/epistemological model of the domain it purports to explain. Science just is philosophy of a sort(s). Third, on a more prescriptive note, even philosophy as practised apart from science ought to be informed by our scientific knowledge base at any given time. One philosophical assumption that I think any scientific account of conscious- ness must make (or science in general for that matter) is that of monism. Positing monism is a necessary (though not sufficient) condition for bridging the ontological/ explanatory gap as well as providing a satisfactory account of ‘mental causation’. Though contrary to popular belief I don’t think it matters much from the scientific perspective what kind of monism you adopt. Any kind of monism (physicalism, neutral monism, panexperiential monism, etc.) short of full-blooded idealism will leave scientific questions largely untouched and scientific practice unchanged. As Sklar puts it: Even if we no longer believed in matter, but perhaps, only in ‘ideas in the mind’ or ‘monads’ or ‘well-founded phenomena’, we could and would still hold on to many of the ‘smaller’ theories we had constructed earlier on the basis of the presupposition that matter existed. Whether the earth’s crust is a portion of a really existing material world or, instead, nothing but a systematically correlated collection of ideas in minds, the issue of whether or not plate tectonics gives a correct account of the dynamical changes in the earth’s crustal features remains unaffected (1999, p. 97). Another well known example of Sklar’s point is the fact that Berkeley himself was an atomist. Assuming the falsity of full-blooded idealism, Sklar’s point applies equally to the questions of consciousness. Copyright (c) Imprint Academic 2011 For personal use only -- not for reproduction 64 M. SILBERSTEIN (2) How is it conceivable/possible that conscious states qua consciousness can causally interact with neurochemical states qua neurochemical? Or if you prefer, how is mental causation possible? You might ask, ‘Why do you assume that consciousness is causally efficacious?’ After all, epiphenomenalism itself (non-interactive dualism), and those views such as nonreductive physicalism that imply ‘epiphenomenalism’, deny the causal efficacy of consciousness. As Flanagan notes ‘the epiphenomenalist suspicion is extraordinarily hard to dispel’ (1992, p. 133). Many people have argued either that whatever causal role con- sciousness is alleged to play could be accounted for by some purely functional or neural mechanism (Block, 1995) or, that our best physical/scientific accounts of the world actually preclude the efficacy of consciousness (Kim, 1993; Levine, 2001). On the other hand, ‘It seems overwhelmingly obvious that mental phe- nomena are both causes and effects of non-mental, physical phenomena’ (Levine, 2001, p. 5). Physical phenomena such as light waves cause me to have conscious experiences such as colour experiences, strong emotions cause me to engage in various behaviours, e.g., bodily movements.