Richard Brown

At this point in time the two-dimensional (2D) argument against physicalism is well known (Chalmers 2009; 2010), as are the many responses to it. However there has been a recent development that has yet to be widely discussed. Some philosophers have argued that we have equally compelling reasons to think that dualism is false based on the conceivability of mere physical duplicates which enjoy conscious experience in just the way we do (Martin 1998; Sturgeon 2000; Piccinini 2006; Frankish 2007; Brown 2010; Balog MS). This argument has not yet been properly understood and in this paper I aim to correct the most common misunderstandings.

Theories of consciousness can be separated into those that see it as cognitive in nature, or as an aspect of cognitive functioning, and those that see consciousness as importantly distinct from any kind of cognitive functioning. One version of the former kind of theory is the higher-order-thought theory of consciousness. This family of theories posits a fundamental role for cognitive states, higher-order thought-like intentional states, in the explanation of conscious experience. These states are higher-order in that they represent the subject herself as being in various world-directed first-order states and thus constitute a kind of cognitive access to one's own mental life. This distinctive cognitive access is postulated to account for what it is like for one to have a conscious experience. One important challenge to this approach is Block's case for phenomenological overflow (Block, 2007, 2011, 2012). The basic argument is that, overall, the balance of evidence favors the identification of phenomenal consciousness with first-order non-cognitive states rather than our cognitive access to those states. Emerging clearly from the ensuing debate is that Block's argument is meant to establish that phenomenology overflows working memory. This is important because, unlike other theories, the higher-order thought theory can allow that our conscious experience overflows working memory. In addition, it can account for the subjective impression that there is overflow even if there isn't.

Philosophers have been talking about brain states for almost 50 years and as of yet no one has articulated a theoretical account of what one is. In fact this issue has received almost no attention and cognitive scientists still use meaningless phrases like 'C-fiber firing' and 'neuronal activity' when theorizing about the relation of the mind to the brain. To date when theorists do discuss brain states they usually do so in the context of making some other argument with the result being that any discussion of what brain states are has a distinct en passant flavor. In light of this it is a goal of mine to make brain states the center of attention by providing some general discussion of them. I briefly look at the argument of Bechtel and Mundale, as I think that they expose a common misconception philosophers had about brain states early on. I then turn to briefly examining Polger's argument, as I think he offers an intuitive account of what we expect brain states to be as well as a convincing argument against a common candidate for knowledge about brain states that is currently "on the scene." I then introduce a distinction between brain states and states of the brain: Particular brain states occur against background states of the brain. I argue that brain states are patterns of synchronous neural firing, which reflects the electrical face of the brain; states of the brain are the gating and modulating of neural activity and reflect the chemical face of the brain

This highly technical book is densely packed with arguments and is an important addition to the literature. Even if one ultimately disagrees with Chalmers there is much to be gained in his exhaustive study, and he goes out of his way to show how one can accept limited or modified versions of scrutability. It is impossible for me to do justice to his argumentative rigor and comprehensive coverage of possible views in the space I have here. In the end I find much of what Chalmers says convincing but something of a Pyrrhic victory.

Among our conscious states are conscious thoughts. The question at the center of the recent growing literature on cognitive phenomenology is this: In consciously thinking P, is there thereby any phenomenology—is there something it’s like? One way of clarifying the question is to say that it concerns whether there is any proprietary phenomenology associated with conscious thought. Is there any phenomenology due to thinking, as opposed to phenomenology that is due to some co-occurring sensation or mental image? In this paper we will present two arguments that a “yes” answer to this question of cognitive phenomenology can be obtained via appeal to the HOT theory of consciousness, especially the version articulated and defended by David Rosenthal.

In recent times we have seen an explosion in the amount of attention paid to the conscious brain from scientists and philosophers alike. One message that has emerged loud and clear from scientific work is that the brain is a dynamical system whose operations unfold in time. Any theory of consciousness that is going to be physically realistic must take account of the intrinsic nature of neurons and brain activity. At the same time a long discussion on consciousness among philosophers has resulted in our distinguishing several kinds of consciousness. So when we ask where the place of consciousness is in nature we may mean several different things. In this chapter I will argue that it is plausible that all of the kinds of consciousness turn out to be nothing but patterns of synchronized neural activity in various frequencies against a dynamically changing chemical background.