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But in the case of consciousness the Darwinian explanation does not tell us what we need to know, for the simple reason that it is unclear how matter can be so organized as to create a conscious being. The problem is in the raw materials. It looks as if with consciousness a new kind of reality has been injected into the universe, instead of just a recombination of the old realities. Even if minds showed no hint of design, the same old problem would exist: How can mere matter originate consciousness? How did evolution convert the water of biological tissue into the wine of consciousness? Consciousness seems like a radical novelty in the universe, not prefigured by the after-effects of the Big Bang, so how did it contrive to spring into being from what preceded it.

But who, in that case, can be watching this pixilated show? The answer is straightforward: no one. There is no distinct "self" in there, beyond the brain as a whole. On the other hand, almost every part of the brain is being "watched" by some other part of the brain, often by several other parts at once.

You came to this book assuming that the basic units of human cognition are states such as thoughts, beliefs, perceptions, desires, and preferences. That assumption is natural enough: it is built into the vocabulary of every natural language. And each state is typically identified by way of a specific sentence in one's natural language: one has the belief that P, or the desire that Q, for example, where P and Q are sentences. Human cognition is thus commonsensically portrayed as a dance of sentential or propositional states, with the basic unit of computation being the inference from several such states to some further sentential state. ¶ These assumptions are central elements in our standard conception of human cognitive activity, a conception often called "folk psychology" to acknowledge it as the common property of folks generally. Their universality notwithstanding, these bedrock assumptions are probably mistaken.

The religious hypothesis of mind-body dualism has been in trouble with evolutionary biology, and with several other sciences as well, for more than a century. It didn't need any special input from artificial intelligence or neuroscience to make it scientifically implausible. I bring it up here only because it is a clear example of a popular and important belief currently under siege by modern information. And because its example may be repeated. The fact is, there is a much more intriguing area of current conceptual commitment, one more likely to be affected by emerging cognitive theory in particular. It lies even closer to home and is even more widespread, if that is possible, than mind-body dualism. It is our current self-conception: our shared portrait of ourselves as self-conscious creatures with beliefs, desires, emotions, and the power of reason.

Your brain is far too complex and mercurial for its behavior to be predicted in any but the broadest outlines or for any but the shortest distances in the future. Faced with the extraordinary dynamical features of a functioning brain, no device constructible in this universe could ever predict your behavior, or your thoughts, with anything more than merely statistical success. ¶ So one need not fear being reduced to a clanking robot or an empty machine. Quite to the contrary, we are now in a position to explain how our vivid sensory experience arises in the sensory cortex of our brains: how the smell of baking bread, the sound of an oboe, the taste of a peach, and the color of a sunrise are embodied in a vast chorus of neural activity. We now have the resources to explain how the motor cortex, the cerebellum, and the spinal cord conduct an orchestra of muscles to perform the cheetah's dash, the falcon's strike, or the ballerina's dying swan. ... On this matter of conceptual development there is especial cause for wonder. For the human brain, with a volume of roughly a quart, encompasses a space of conceptual and cognitive possibilities that is larger, by one measure at least, than the entire astronomical universe. It has this striking feature because it exploits the combinatorics of its 100 billion neurons and their 100 trillion synaptic connections with each other.

My guess is that this cosmic authority problem is not a rare condition and that it is responsible for much of the scientism and reductionism of our time. One of the tendencies it supports is the ludicrous overuse of evolutionary biology to explain everything about life, including everything about the human mind. Darwin enable modern secular culture to heave a great collective sigh of relief, by apparently providing a way to eliminate purpose, meaning, and desiring as fundamental features of the world. Instead they become epiphenomena, generated incidentally by a process that can be entirely explained by the operation of the nonteleogical laws of physics on the material of which we and our environments are all composed. There might still be thought to be a religious threat in the existence of the laws of physics themselves, and indeed the existence of anything at all, but it seems to be less alarming to most atheists.

The really hard problem of consciousness is the problem of experience. When we think and perceive, there is a whir of information-processing, but there is also a subjective aspect. As Nagel (1974) has put it, there is something it is like to be a conscious organism. This subjective aspect is experience. When we see, for example, we experience visual sensations: the felt quality of redness, the experience of dark and light, the quality of depth in a visual field. Other experiences go along with perception in different modalities: the sound of a clarinet, the smell of mothballs. Then there are bodily sensations, from pains to orgasms; mental images that are conjured up internally; the felt quality of emotion, and the experience of a stream of conscious thought. What unites all of these states is that there is something it is like to be in them. All of them are states of experience...It is undeniable that some organisms are subjects of experience. But the question of how it is that these systems are subjects of experience is perplexing. Why is it that when our cognitive systems engage in visual and auditory information-processing, we have visual or auditory experience: the quality of deep blue, the sensation of middle C? How can we explain why there is something it is like to entertain a mental image, or to experience an emotion? It is widely agreed that experience arises from a physical basis, but we have no good explanation of why and how it so arises. Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does. If any problem qualifies as the problem of consciousness, it is this one.