The Mysterious Flame

One of the most ancient of human experiences is the perception of a distinction between the world and the mind that perceives the world. The question of how the ideas, images, and feelings that occur in the mind are related to the physical world inspired the work of Plato, giving rise to the Western philosophical tradition. With the rise of the mechanistic, scientific worldview in early modern Europe, the question took on a new form and a new urgency. If the universe consists of a series of causes and effects among objects, how is it possible for human beings to be subjects who are aware of the objects and act on them? Belgian philosopher René Descartes (1596-1650) offered a brilliant solution to this problem by essentially dividing humans into two parts: Humans, Descartes concluded, consist of a material body that participates fully in the causal relationships of other objects and an immaterial soul or mind that perceives and acts upon the body and the physical world.

The dualism of Descartes continues to be one theoretical approach to the nature of consciousness. However, two new areas of development in science have made this kind of mind-body separation increasingly difficult to support. First, advances in neuroscience indicate that events in the mind are directly dependent upon the brain, a physical object. Second, the development of computers that seem to be able to do some of the work of human minds suggests that it may be possible to conceive of physical objects as producing mental processes. Nevertheless, humans still do not understand just how the masses of neuronal connections that make up their brains could give rise to experiences of the world.

The problem of consciousness, with its relevance to both neuroscience and artificial intelligence, has become one of the hottest issues in contemporary philosophy. Colin McGinn, a British philosopher teaching at Rutgers University in New Jersey in the late 1990’s, offers a readable introduction to this philosophical problem in The Mysterious Flame. McGinn proudly proclaims himself a “mysterian,” a label other philosophers have taken from the 1960’s pop group Question Mark and the Mysterians and applied to those who claim that consciousness is simply a mystery that cannot be explained.

McGinn’s mysterian position is not a form of mysticism. He does not claim that consciousness is a phenomenon that exists outside reason and beyond physical science. Instead, he essentially argues that human consciousness has not evolved in order to explain itself and is therefore incapable of doing so.

McGinn describes and criticizes the two main positions on consciousness: materialism and dualism. The materialist position holds that consciousness can be reduced to material events in the brain, to electrochemical connections among neurons. There is a big gap, McGinn argues, between neuronal processes and experiences. The perception of the color red and the feeling of pain are different from the movement of neurotransmitters across synapses. One could open up a brain and observe the patterns of discharges of someone seeing red, but nowhere would one see the actual experience of someone seeing red.

The classical dualist position is also indefensible. Dualism is haunted by problems McGinn describes as the “zombie problem” and the “ghost problem.” If mind and brain are completely separate, then one could, in theory, simply remove consciousness, and the individual without consciousness would go about all the tasks of life as a zombie without any awareness or inner experience. In this case, however, the mind would simply be irrelevant, an observer with no power to bring about action. The “ghost problem” presents an even more serious difficulty with dualism. If the mind exists in the brain only as an immaterial presence without substance, then how can the mind cause the unquestionably physical body to do things? Why, moreover, do parts of consciousness, such as memories or emotions, change in response to brain damage? Alzheimer’s disease seems like a convincing demonstration of the dependence of consciousness on the physical state of the brain.

All the explanations one can produce to explain consciousness fail, McGinn argues, because human scientific intelligence is limited. Science and philosophy are results of applying mental faculties developed through evolution to new kinds of problems. Evolution cannot have resulted in infinitely powerful mental faculties, though, so there must be some kinds of problems that humans are unable to solve. When one reaches these kinds of problems, McGinn argues, one has reached a...

(The entire section is 1896 words.)