Tom Polger

The 1990’s, we’ve been told, were the decade of the brain. But without anyone announcing or declaring, much less deciding that it should be so, the 90’s were also a breakthrough decade for the study of consciousness. (Of course we think the two are related, but that is another matter altogether.) William G. Lycan leads the charge with his 1987 book Consciousness (MIT Press), and he has weighed-in again with Consciousness and Experience (1996, MIT Press). Together these two books put forth Lycan’s formidable view of consciousness, extending the theory of mind that he calls ‘homuncular functionalism.’ Roughly, Lycan’s view is that conscious beings are hierarchically composed intentional systems, whose representational powers are to be understood in terms of their biological function. In this review we will call the view ‘teleological functionalism’ or ‘teleofunctionalism’ – the homuncular part, for which Lycan and Daniel Dennett argued convincingly, is now so widely accepted that it fails to distinguish Lycan’s view from other versions of functionalism. This, by itself, is a testament to the importance of Lycan’s work.

Suppose that consciousness is a natural feature of biological organisms, and that it is a capacity or property or process that resides in a single organ. In that case there is a straightforward question about the consciousness organ, namely: How did the consciousness organ come to be formed and why is its presence maintained in those organisms that have it? Of course answering this question might be rather difficult, particularly if the consciousness organ is made of soft tissue that leaves at best indirect fossil records, or if it has been fixed in the populations for such a long time that there are few available examples of organisms that lack the consciousness organ on which to conduct comparative experiments. No doubt there are other confounding practical obstacles as well. But these are just the complications that face biologists and natural historians on a regular basis, and they do not reflect any special problems about the study of consciousness. This is just to say that if consciousness is a natural feature of biological organisms then its origins and history can be studied in the same manner as other features of the biological world. It’s a hard business, but biologists are pretty good at it

In Natural Minds Thomas Polger advocates, and defends, the philosophical theory that mind equals brain -- that sensations are brain processes -- and in doing so brings the mind-brain identity theory back into the philosophical debate about consciousness. The version of identity theory that Polger advocates holds that conscious processes, events, states, or properties are type- identical to biological processes, events, states, or properties -- a "tough-minded" account that maintains that minds are necessarily indentical to brains, a position held by few current identity theorists. Polger's approach to what William James called the "great blooming buzzing confusion" of consciousness begins with the idea that we need to know more about brains in order to understand consciousness fully, but recognizes that biology alone cannot provide the entire explanation. Natural Minds takes on issues from philosophy of mind, philosophy of science, and metaphysics, moving freely among them in its discussion.Polger begins by answering two major objections to identity theory -- Hilary Putnam's argument from multiple realizability and Saul Kripke's modal argument against mind-brain identity. He then offers a detailed account of functionalism and functional realization, which offer the most serious obstacle to consideration of identity theory. Polger argues that identity theory can itself satisfy the kind of explanatory demands that are often believed to favor functionalism.

Saying that psychological states are functional states, the functionalist claims more than that psychological states have functions. Rather, functionalism is the theory that psychological states are defined and constituted by their functions. On this view, what it is to be a psychological state of a certain sort just is and consists entirely of having a certain function. Anything that has that function in a suitable system would therefore be that psychological state. If storing information for later use is the essential function of memory, then anything that has that function counts as a memory. Similarly, one might say that anything that traps or kills mice counts as a mouse trap

There is an argument for functionalism—and _ipso facto_ against identity theory—that can be sketched as follows: We are, or want to be, or should be dedicated to functional explanations in the sciences, or at least the special sciences. Therefore—according to the principle that what exists is what our ideal theories say exists—we are, or want to be, or should be committed to metaphysical functionalism. Let us call this the _argument from functional_ _explanation_. I will try to reveal the motivation for making such an argument, and sketch the kind of response that should be made by critics of functionalism.

Consciousness and evolution are complex phenomena. It is sometimes thought that if adaptation explanations for some varieties of consciousness, say, conscious visual perception, can be had, then we may be reassured that at least those kinds of consciousness are not epiphenomena. But what if other varieties of consciousness, for example, dreams, are not adaptations? We sort out the connections among evolution, adaptation, and epiphenomenalism in order to show that the consequences for the nature and causal efficacy of consciousness are not as dire as has sometimes been supposed.

Forthcoming in Philosophy of Science. Despite some recent advances, multiple realization remains a largely misunderstood thesis. Consider the dispute between Lawrence Shapiro and Carl Gillett over the application of Shapiro’s recipe for deciding when we have genuine cases of multiple realization. I argue that Gillett follows many philosophers in mistakenly supposing that multiple realization is absolute and transitive. Both of these are problematic. They are tempting only when we extract the question of multiple realization from the explanatory context in which it is invoked. Anchoring multiple realizability in its theoretical context provides grounds for arbitrating disagreements. Doing so, I argue, favors the view advanced by Shapiro.

A common view is that the truth of multiple realization—e.g., about psychological states—entails the truth of functionalism. This is supposed to follow because what is multiply realized is eo ipso realized. I argue that view is mistaken by demonstrating how it misrepresents arguments from multiple realization. In particular, it undermines the empirical component of the arguments, and renders the multiplicity of the realization irrelevant. I suggest an alternative reading of multiple realizability arguments, particularly in philosophy of psychology. And I explain the proper way to understand the relation between realization and multiple realization

Saul Kripke’s modal essentialist argument against materialism remains an obstacle to any prospective Identity Theorist. This paper is an attempt to make room for an Identity Theory without dismissing Kripke’s analytic tools or essentialist intuitions. I propose an explanatory model that can make room for the Identity Theory within the constraints of Kripke’s view; the model is based on ideas from Alan Sidelle’s, “Identity and Identity-like” . My model explains the apparent contingency of some scientific identities by appealing to our epistemic access to the conditions of identity for sensations and brain processes. Pace Kripke, the Identity Theorist can thus explain away the apparent contingency of mind-brain identity claims

Recently some philosophers interested in consciousness have begun to turn their attention to the question of what evolutionary advantages, if any, being conscious might confer on an organism. The issue has been pressed in recent dicussions involving David Chalmers, Todd Moody, Owen Flanagan and Thomas Polger, Daniel Dennett, and others. The purpose of this essay is to consider some of the problems that face anyone who wants to give an evolutionary explanation of consciousness. We begin by framing the problem in the context of some current debates. Then we.

In this article I reply to the challenge set forth by Dennett in his critique of Flanagan and Polger (1995). Through careful textual analysis, I show that Dennett is presenting us with a dilemma and that this dilemma is the keystone of Dennett’s argument in his Consciousness Explained. I argue that one horn of the dilemma does not have the consequence that Dennett claims; Specifically, I argue that theories that allow for the possibility of non-conscious functional duplicates of conscious beings (so called zombies) do not thereby entail epiphenomenalism about consciousness. I demonstrate how Dennett’s argument falls prey to a common mistake in reasoning about the functions of things, and recommend a correction.

By now it is cliché to observe that so-called reductionism is not one mammoth doctrine. There are, as it were, many reductionisms. Needless to say, there are at least as many antireductionisms. Despite the fact that neither reductionisms nor their counterparts are single and unified doctrines there do seem to be some family resemblances. One, it seems to me, is that both reductionisms and antireductionisms are acute responses to certain metaphysical worries. Some of these worries are metaphysical in nature, and others are worries about the nature of metaphysics. My contention is that these worries are by and large misguided, and thus that the anxious reactions of both reductionists and antireductionists are unwarranted. For the present purposes I will distinguish between reductionist and antireductionist theses, on the one hand, and reductionist and antireductionist approaches, on the other. This is a perhaps clumsy distinction, and I don’t know that it carves reductionism at its joints. But I think it can be made to do some work. By theses I have in mind particular views about the nature of reduction and reductive relations, which can be worked out in various ways some of which will be discussed below. By approaches I have in mind the motivations and background assumptions that go into formulating or adopting particular theses. Individual reductionists and antireductionists usually hold what we might then call a theory, a combination of an approach and a thesis. A great deal has been written about the merits of or truth of any number of 1 reductionist or antireductionist theses. Presumably there are some assumptions about approaches and motivations lurking in the background. But very little has been said about the merits of the various approaches themselves. Put another way: There is a lively debate over whether particular reductionist theses can solve certain problems or avoid certain objections. But not enough attention has been given to whether these are problems worth solving or objections worth overcoming.