Today’s issue of Science has a letter from neuroscientist Martha Farah and theologian Nancey Murphy warning against ‘non-materialist neuroscience’ becoming the new front-line in the religion wars.
Most religions endorse the idea of a soul (or spirit) that is distinct from the physical body. Yet as neuroscience advances, it increasingly seems that all aspects of a person can be explained by the functioning of a material system. This first became clear in the realms of motor control and perception. Yet, models of perceptual and motor capacities such as color vision and gait do not directly threaten the idea of the soul. You can still believe in what Gilbert Ryle called “the ghost in the machine” and simply conclude that color vision and gait are features of the machine rather than the ghost.
However, as neuroscience begins to reveal the mechanisms underlying personality, love, morality, and spirituality, the idea of a ghost in the machine becomes strained. Brain imaging indicates that all of these traits have physical correlates in brain function. Furthermore, pharmacologic influences on these traits, as well as the effects of localized stimulation or damage, demonstrate that the brain processes in question are not mere correlates but are the physical bases of these central aspects of our personhood. If these aspects of the person are all features of the machine, why have a ghost at all?
By raising questions like this, it seems likely that neuroscience will pose a far more fundamental challenge than evolutionary biology to many religions. Predictably, then, some theologians and even neuroscientists are resisting the implications of modern cognitive and affective neuroscience. “Nonmaterialist neuroscience” has joined “intelligent design” as an alternative interpretation of scientific data. This work is counterproductive, however, in that it ignores what most scholars of the Hebrew and Christian scriptures now understand about biblical views of human nature. These views were physicalist, and body-soul dualism entered Christian thought around a century after Jesus’ day.
As I’ve noted before, I remain sceptical that this will pose much of a threat, largely due to the fact that non-materialist neuroscience is not particularly new – many famous neuroscientists (including the Nobel prize-winning John Eccles) have been explicitly non-materialist with few contemporary ripples.
Unlike evolution, which bluntly contradicts what many religious texts claim, very few holy books describe any concepts of the soul that can be directly contradicted by neuroscience.
However, there is certainly some interest in the neuroscience bashing among Christian fundamentalists, who recently held their first conference on the issue. We shall have to see how successfully they manage to enthuse their flock.