Tom Polger

Reasoning about consciousness concerns theoretical connections between the etiology of consciousness and philosophical theories of its nature. Discussions concerning the origins of consciousness are different from those about the origins of hearts, lungs, and stomachs. And it is these lines of reasoning that concern this chapter. Before examining some arguments concerning the evolution of consciousness, we need to understand what a good explanation of the adaptation of consciousness would look like. The chapter outlines a few explanations of the etiology of consciousness that attempt to go beyond just‐so stories. It uses the terminology of evolutionary theory, the theory of the origins and natural histories of organisms and their traits. The chapter then evaluates the role that evolutionary explanations are claimed to play in broader theorizing about consciousness. It also considers some of the most prominent questions that arise in evolutionary reasoning about consciousness.

G. E. Moore argues that goodness is an intrinsic non-natural property that supervenes irreducibly on the intrinsic natural properties of its bearers. Accordingly, it is often supposed that “Moorean” supervenience is incompatible with physicalism, a naturalistic thesis. In this paper I argue that Moorean supervenience is not in itself incompatible with physicalism, Moore’s ethical non-naturalism notwithstanding. Understanding why will help us to better appreciate the full range of resources available to physicalists.

Mental and physical causes do not competedthe presence of one does not exclude the efficacy of the other. This point is obvious from the perspective of an interventionist theory of causation, but only when this theory gets its proper due. Doubts about the interventionist justification for concluding that there is both physical and mental causation, we have argued, rest on misunderstandings of interventionism. When looking to interventions to reveal causal structures, care must be taken to consider the right variable sets. Jaegwon Kim’s diagram is the wrong starting point for interventionist causal reasoning because it includes variables that are related by non-causal relations in addition to causal relations. When it comes to understanding exclusion, less is more.

According to the multiple realization argument, mental states or processes can be realized in diverse and heterogeneous physical systems; and that fact implies that mental state or process kinds cannot be identified with particular kinds of physical states or processes. More specifically, mental processes cannot be identified with brain processes. Moreover, the argument provides a general model for the autonomy of the special sciences. The multiple realization argument is widely influential, but over the last thirty years it has also faced serious objections. Despite those objections, most philosophers regard the fact of multiple realization and the cogency of the multiple realization argument as plainly correct. Why is that? What is it about the multiple realization argument that makes it so resilient? One reason is that the multiple realization argument is deeply intertwined with a view that minds are, in some sense, computational. But we argue that the sense in which minds are computational does not support the conclusion that they are ipso facto multiply realized. We argue that the sense in which brains compute does not imply that brains implement multiply realizable computational processes, and it does not provide a general model for the autonomy of the special sciences.

This collection offers cutting-edge chapters on themes related to the philosophical work of Owen Flanagan. Flanagan is an influential philosopher in the late 20th and early 21st Century, whose wide-ranging work spans philosophy of mind (especially consciousness, identity, and the self), ethics and moral psychology, comparative philosophy, and philosophical study of psychopathology (especially disorders of self, dreams, and addiction). Flanagan is the author of numerous scholarly and popular articles, and of 10 books. The chapters present proposals for productive interdisciplinary research exploring the mind, ethics, personhood, consciousness, religious cognition, mental disorders, addiction, the narrative self, virtue, the social sciences, forgiveness, or comparative philosophy.

Godfrey-Smith begins with the particular, with the peculiarities of some creatures in a small corner of the animal kingdom, and builds up his reasoning and evidence through a series of detailed comparisons with other creatures. He often finds that similar effects have different causes, and appears to rely on the inverse of the Newtonian principle, namely, that similar causes will have similar effects. But the similarities and differences that occupy Godfrey-Smith are not only or mainly by comparison with humans or mammals. His story is as much about how octopuses and cuttlefish differ from other mollusks and from their common ancestors as about how they behave in ways commonly associated with vertebrates.

Most practitioners of the metaphysics of science agree that it should be a naturalized metaphysics. But, just as in other areas of philosophy, there is no consensus on what constitutes naturalism. Here I will focus on just one aspect, viz., the idea that the metaphysics of science should be epistemically naturalized. In the first section I will characterize the kind of epistemic naturalism relevant to the metaphysics of science. The main idea, drawing on the work of Penelope Maddy, is that metaphysical inquiry is to be conducted and metaphysical claims justified in the very same way that scientific inquiry is conducted and scientific claims are justified. I then examine two prominent examples of metaphysicians of science proposing to “naturalize” the metaphysics of science, and argue that they fail to be epistemically natural. These are approaches due to James Ladyman and Don Ross, and to Anjan Chakravartty. Considering their failures shows us a way forward for naturalized metaphysics of science that is both more metaphysical and more scientific.

Since Hilary Putnam offered multiple realization as an empirical hypothesis in the 1960s, philosophical consensus has turned against the idea that mental processes are identifiable with brain processes, and multiple realization has become the keystone of the 'antireductive consensus' across philosophy of science. Thomas W. Polger and Lawrence A. Shapiro offer the first book-length investigation of multiple realization, which serves as a starting point to a series of philosophically sophisticated and empirically informed arguments that cast doubt on the generality of multiple realization in the cognitive sciences. They argue that mind-brain identities have played an important role in the growth and achievements of the cognitive sciences, and suggest that there is little prospect for multiple realization in an empirically-based theory of mind. This leads Polger and Shapiro to offer an alternative framework for understanding explanations in the cognitive sciences, as well as in chemistry, biology, and other non-basic sciences.

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 . 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

According to the received view in philosophy of mind, mental states or properties are _realized_ by brain states or properties but are not identical to them. This view is often called _realization_ _physicalism_. Carl Gillett has recently defended a detailed formulation of the realization relation. However, Gillett’s formulation cannot be the relation that realization physicalists have in mind. I argue that Gillett’s “dimensioned” view of realization fails to apply to a textbook case of realization. I also argue Gillett counts as realization some cases that should not count if realization physicalism is to be distinguished from its competitors in the usual ways. I conclude that the relation described by Gillett cannot be realization

My topic is the confluence of two recently active philosophical research programs. One research program concerns the metaphysics of realization. The other research program concerns scientific explanation in terms of mechanisms. In this paper I introduce a distinction between descriptive and explanatory approaches to realization. I then use this distinction to argue that a well-known account of realization, due to Carl Gillett, is incompatible with a well-known account of mechanistic explanation, due to Peter Machamer, Lindley Darden, and Carl Craver (MDC, Philos Sci 57: 1-25, 2000). This is surprising, not least of which because Gillett has cited MDC's work as evidence that his account of realization is the right way to think about realization in the sciences

In the early years of the 1990s, a number of philosophers and cognitive scientists became enthused about the idea that mental states are spatially and temporally distributed in the brain, and that this has significant consequences for philosophy of mind. Daniel Dennett (1991), for example, appealed to the spatial and temporal distribution of cognitive processes in the brain in order to argue that there is no unified place where or time when consciousness occurs in the brain. Dennett used this interim conclusion as a premise in a series of arguments designed to undermine what he calls the “Cartesian Theater” view of consciousness, according to which there is an independent and fact of the matter about when and where conscious mental states occur. Most famously, Dennett argues that anyone who believes there are such facts of the matter must choose between “Orwellian” and “Stalinesque” theories of the timing of consciousness, in order to accommodate certain data about the spatial distribution of the timing of consciousness-related brain events. But, he claims, that distinction is a distinction without a difference: The choice between “Orwellian” and “Stalinesque” views is either nonsense, or at the very least one that we could never be justified in making. And this, Dennett takes it, is a reductio ad absurdum of any theory of consciousness that says there is a fact of the matter about when and where is occurs

It is commonly held that there are two obstacles to precisely formulating the doctrine of physicalism: Hempel’s Problem, and Hume’s Problem.² Hempel’s Problem is that if physicalism is to be formulated in terms of physics—or in terms of any science, for the problem is fully general if it is a problem at all—whether to use the current or future science. If physicalism is formulated in terms of current physics, then it is most likely false because current physics is at least very likely to be false and is perhaps known to be incomplete or inconsistent. If physicalism is formulated in terms of future physics, then (the worry goes) physicalism will prove to be trivial, vacuous, or simply of indeterminate content. Horgan offers no direct guidance on Hempel’s Problem, though he seems to adopt a future-physics view.³

A widely accepted theory holds that emotional experiences occur mainly in a part of the human brain called the amygdala. A different theory asserts that color sensation is located in a small subpart of the visual cortex called V4. If these theories are correct, or even approximately correct, then they are remarkable advances toward a scientific explanation of human conscious experience. Yet even understanding the claims of such theories—much less evaluating them—raises some puzzles. Conscious experience does not present itself as a brain process. Indeed experience seems entirely unlike neural activity. For example, to some people it seems that an exact physical duplicate of you could have different sensations than you do, or could have no sensations at all. If so, then how is it even possible that sensations could turn out to be brain processes?

On the one hand, it is obvious that a person’s conscious experiences are unified with one another in a way that they are not unified with anyone else’s experiences. My experiences are mine, and yours are not. On the other hand, it is equally plain that a person’s experiences are not monolithic. Generally, I can distinguish various aspects of my experiences, and I can attend to some rather than others. Conscious experience is unified, and it is not. Is there a unification thesis that is substantial, interesting and plausible? Tim Bayne sets out to defend an affirmative answer in his The Unity of Consciousness.

Karen Bennett has recently articulated and defended a “compatibilist” solution to the causal exclusion problem. Bennett’s solution works by rejecting the exclusion principle on the grounds that even though physical realizers are distinct from the mental states or properties that they realize, they necessarily co-occur such that they fail to satisfy standard accounts of causal over-determination. This is the case, Bennett argues, because the causal background conditions for core realizers being sufficient causes of their effects are identical to the “surround” conditions with which the core realizers are metaphysically sufficient the states or properties that they realize. Here we demonstrate that the background conditions for the causal sufficiency of core realizers for their effects are not identical to the core realizer’s surrounds, nor do backgrounds necessitate such surround conditions. If compatibilist solutions to exclusion can be defended, a different argument will be needed

Drew Khlentozos’ Naturalistic Realism and the Antirealist Challenge is a meticulous introduction and roadmap to the core arguments of the contemporary realism/antirealism debate. It has several features that I especially admire. The book is carefully argued and for the most part clearly written. Rare among recent writers in Anglo-American philosophy, Khlentzos is a charitable reader of his opponents and earnestly endeavors to present their views as clearly and generously as possible. This generosity and thoroughness are also the book’s main fault, as it is long (weighing in 408 pages) and sometimes plodding. In a few cases Khlentzos’ charity is overly generous. This seems to me to be the case, for example, with some of his contortions on behalf of Dummett, not least of which being a lengthy chapter on how intuitionism drives Dummett’s antirealism that probably should have been an appendix. But these are drawbacks that we can all live with—especially for the purpose of graduate teaching, for which this monograph is well suited. Naturalistic Realism and the Antirealist Challenge begins (Section I) by setting out the realist/anti-realist debate. Khlentzos argues that the kinds of metaphysical realists who have been quickest to shrug off semantic arguments against realism are particularly susceptible to those arguments. Specifically, naturalistic realists—among whom Khlentzos counts himself—cannot dismiss critiques like those from Dummett and Putnam merely by observing that realism is a metaphysical rather than semantic or epistemic doctrine. The trouble is, “If the world is as resolutely mind-independent as the realist makes out, then there is a problem about how we get to know about it in the first place” (4). Khlentzos calls this the representation problem, saying.

The enduring metaphysical question about minds and mental phenomena concerns their nature. At least since Descartes this question—the mind-body problem—has been understood in terms of the viability or necessity of mind-body dualism, the thesis that minds and bodies are essentially distinct kinds of substance. Assuming that the nonmental (‘body’) portions of the world are constituted of physical stuff, the remaining question is: Are minds or mental phenomena essentially distinct non-physical substances, or phenomena that essentially involve such distinct kinds of substances? By the middle of the Twentieth Century there was broad philosophical and scientific consensus that the answer to this classical question about minds is negative: Minds and mental phenomena are not essentially distinct substances, nor are they phenomena that essentially involve distinct kinds of substances. There are at least two broad trends and one specific argument that lead to this conclusion. One trend is the decreasing influence of specifically theological arguments and commitments in philosophical argumentation, so that religious belief in immortal souls was no longer given much weight in the ontology of mind. The second trend, perhaps related to the first, is the increased demand that metaphysical theories bear explanatory fruits, so that the postulation of an immaterial and essentially mental substance appears to be a abdication from explanatory duties rather than a useful proposal. The argument, known to Descartes from the very beginning, is that there has never been an adequate account of 1 how two essentially distinct and incompatible substances could causally interact.1 Descartes’ solution was inadequate and brute, and his followers struggled with the problem—leading to Leibniz’s parallelism and Malebranche’s occasionalism, among other views. The problem of mental causation, then, is the central difficulty that underines substance dualism.2 The negative answer on the question of substance dualism, however, only increases the pressure for some monistic account of the nature of minds..

Consider what the brain-state theorist has to do to make good his claims. He has to specify a physical–chemical state such that any organism (not just a mammal) is in pain if and only if (a) it possesses a brain of suitable physical–chemical structure; and (b) its brain is in that physical–chemical state. This means that the physical–chemical state in question must be a possible state of a mammalian brain, a reptilian brain, a mollusc’s brain (octopuses are mollusca, and certainly feel pain), etc. At the same time, it must not be a possible (physically possible) state of the brain of any physically possible creature that cannot feel pain. Even if such a state can be found, it must be nomologically certain that it will also be a state of the brain of any extraterrestrial life that may be found that will be capable of feeling pain before we can even entertain the supposition that it may be pain. It is not altogether impossible that such a state will be found... . But this is certainly an ambitious hypothesis. (Putnam 1967/1975, p. 436) The belief that mental states are multiply realized is now nearly universal among philosophers, as is the belief that this fact decisively refutes the identity theory. I argue that the empirical support for multiple realization does not justify the confidence that has been placed in it. In order for multiple realization of mental states to be an objection to the identity theory, the neurological differences among pains, for example, must be such as to guarantee that they are of distinct neurological kinds. But the phenomena traditionally cited do not provide evidence of that sort of variation. In particular, examples of neural plasticity do not provide such evidence.

Fifty years ago J. J. C. Smart published his pioneering paper, “Sensations and Brain Processes.” It is appropriate to mark the golden anniversary of Smart’s publication by considering how well his article has stood up, and how well the identity theory itself has fared. In this paper I first revisit Smart’s text, reflecting on how it has weathered the years. Then I consider the status of the identity theory in current philosophical thinking, taking into account the objections and replies that Smart discussed as well as some that he did not anticipate. Finally, I offer a brief manifesto for the identity theory, providing a small list of the claims that I believe contemporary identity theorist should accept. As it turns out, these are more or less the ones that Smart defended fifty years ago.

Michael Tye has recently been a vocal defender of color realism or, as I shall call it, color objectivism. Objectivism about color is the view that color properties are identical to intrinsic physical properties of the surfaces of objects. Subjectivism about color is the denial of color objectivism. Objectivists argue that color claims must be taken at face value. In this paper I forego the usual bickering about whether there are surface reflectance properties that can be identified with colors as the objectivist theory requires. Supposing that some such properties could be found, I argue that if objectivism about color were correct it would have the unsavory consequence that we are rarely if ever right—perhaps never right—about the particular colors of particular things. So objectivism does not bear out common attribution of colors to the surfaces of things, after all.

Multiple realizability has recently attractedrenewed attention, for example Bickle, 1998;Bechtel and Mundale, 1999; Bechtel and McCauley,1999; Heil, 1999; and Sober, 1999. Many of thesewriters revisit the topic of multiplerealizability in order to show that someversion of a mind-brain identity theory isviable. Although there is much of value inthese recent explorations, they do not addressthe underlying intuitions that have vexedphilosophers of mind since Hilary Putnamintroduced the concern (1967). I argue that thestandard way of construing multiplerealizability is a much stronger claim thanthat of Putnam's intuition alone. I distinguishfour interpretations of the multiplerealizability intuition. Some commonformulations of multiple realizability arealmost certainly true, while others are not atall plausible. I argue that the plausible formsof multiple realizability do not impugn theprospects for a mind-brain Identity Theory.

To what degree must the brains and bodies of creatures with minds have to be similar to the brains and bodies of human beings? Since the late 1960’s, most philosophers and cognitive scientists have supposed that there a relatively few constraints on what sorts of brains and bodies can realize minds. It is widely believed that minds are multiply realizable. Of course there were always dissenters, and in recent years their grumbling has grown harder to dismiss. In The Mind Incarnate , Lawrence Shapiro provides the first book-length study of the multiple realizability thesis. Such an examination is long overdue, and Shapiro’s treatment is sure to set the standard for the budding debate

David Chalmers burst onto the philosophical scene in the mid-1990s with his work on consciousness, which awakened slumbering zombie arguments against physicalism and transformed the explanatory gap into the hard problem of consciousness. The distinction between hard and easy problems of consciousness became a central dogma of the movement. Chalmers’ influence in philosophy and consciousness studies is unquestionable. But enthusiasts of Chalmers’ work on consciousness may be excused for not fully appreciating his own justification for drawing the hard/easy distinction, or even exactly which distinction he is drawing. Consequently, it is not clear that the ‘Chalmers’ hard problem’ that has been widely influential is Chalmers’ ‘hard problem’ of consciousness. Chalmers’ ‘hard problem’ rests on, among other things: a methodological view about how philosophy—metaphysics, especially—ought to be conducted; a view about the requirements for explanation and reduction in philosophy and in the sciences; and a theory of the semantics of concepts.1 Although Chalmers writes that the present book is not intended as a foundation for his