One of the more interesting contemporary philosophical debates is that between those who believe that everything can be explained in terms of matter and physics, called materialists, and those who believe that there's more to reality than just atoms and energy. The latter philosophers hold to one kind of dualism or another, and argue that mind (or soul, or spirit) is an irreducible constituent of the cosmos.
Most Christians are dualists. They believe that there's more to an exhaustive explanation of human beings than just a physical description of our chemistry. They hold to the view that the phenomena of our mental experience point to the existence of something both immaterial and critical to a full understanding of living human organisms. The phenomena of consciousness, they argue, simply cannot be explained within the constraints of a materialist worldview.
A recent column by Ray Tallis at New Scientist takes this view and argues that materialist views of consciousness simply fail to account for what we know about our inner experience. He acknowledges that most people who think and write about these matters are materialists, but he thinks they're simply mistaken:
Most neuroscientists, philosophers of the mind and science journalists feel the time is near when we will be able to explain the mystery of human consciousness in terms of the activity of the brain. There is, however, a vocal minority of neurosceptics who contest this orthodoxy. Among them are those who focus on claims neuroscience makes about the preciseness of correlations between indirectly observed neural activity and different mental functions, states or experiences.
Tallis claims that there's a "deep philosophical confusion embedded in the assumption that if you can correlate neural activity with consciousness, then you have demonstrated they are one and the same thing, and that a physical science such as neurophysiology is able to show what consciousness truly is."
Demonstrating a correlation between chemical reactions in the brain and particular states of consciousness, no more demonstrates that consciousness just is a bunch of chemical reactions than demonstrating a correlation between the state of a television set and the image on the screen demonstrates that all that's involved in producing the image is the television set.
Tallis goes on to note that:
... there is an insuperable problem with a sense of past and future. Take memory. It is typically seen as being "stored" as the effects of experience which leave enduring changes in, for example, the properties of synapses and consequently in circuitry in the nervous system. But when I "remember", I explicitly reach out of the present to something that is explicitly past. A synapse, being a physical structure, does not have anything other than its present state. It does not, as you and I do, reach temporally upstream from the effects of experience to the experience that brought about the effects. In other words, the sense of the past cannot exist in a physical system.
Our failure to explain consciousness in terms of neural activity inside the brain inside the skull is not due to technical limitations which can be overcome. It is due to the self-contradictory nature of the task, of which the failure to explain "aboutness", the unity and multiplicity of our awareness, the explicit presence of the past, the initiation of actions, the construction of self are just symptoms.
It's a little technical but the article is nonetheless a good read if you wish to understand why dualists consider the materialist view highly implausible.
RLC