A few months ago, the cognitive archaeologist David Lewis-Williams published Conceiving God: The Cognitive Origin and Evolution of Religion. When I saw the title, I worried that perhaps I had been scooped. Now that I have nearly finished the book, my worry has passed. Lewis-Williams’ title is a bit deceiving, given that the book combines an evolutionary-cognitive explanation for religion with a polemic against religion in the tradition of Richard Dawkins and Sam Harris. Lewis-Williams takes particular aim at Christianity. The book does not, therefore, limit itself to origins and explanations as the title suggests.
When Lewis-Williams confines himself to explaining the origins of supernatural thinking, his primary contention is that such thinking arises from the fluctuations of consciousness. It is a human universal linked to neurological states. Because consciousness is central to his argument, I thought it would be helpful to preface my review (which will appear over the next few days), with a short discussion of consciousness.
There are those who argue, with some force, that we really do not know much about consciousness and cannot say much about it. In his famous essay “What Is It Like To Be a Bat?” (1974), the philosopher Thomas Nagel makes just such a case. There are those (including myself), however, who think that Nagel is a bit too pessimistic and contend we can say something substantive about consciousness. For those who prefer a book length treatment, I recommend Merlin Donald’s A Mind So Rare: The Evolution of Human Consciousness. Donald makes a persuasive case for understanding consciousness and treating it seriously (unlike evolutionary psychologists who relegate consciousness to mere background).
The Conscious Brain
In many respects, the human brain is most remarkable for its conscious properties. Precisely what consciousness is defies easy description or explanation. For humans, it is often associated with attention, focus, and awareness. Francis Crick likens consciousness to a searchlight that deals with current tasks and conditions. Purposive intentionality, goal states, future planning, and voluntary decision-making are all aspects of consciousness. Given our Homo-centric view of the world, many assume that consciousness is a uniquely human attribute. This view is mistaken. While humans possess a type of consciousness that is different, there is no reason to think that other animals are not conscious. Consciousness, in other words, exists along a phylogenetic continuum.
Whether consciousness itself is a direct product of selection or is an emergent feature of neural evolution remains a mystery. We know, however, that mobile organisms face special challenges as they operate in multi-dimensional environments. Sensory inputs must be coordinated with motor outputs in a stable arena of action. For smaller, slower, and less complex organisms, this coordination does not even require a brain, let alone something akin to consciousness. For these organisms, widely distributed basal ganglia are sufficient. For larger, faster, and more complex organisms, a brain – and some form of consciousness – appears to be necessary. If this is the case, it is not unreasonable to suggest that reptiles are minimally conscious and that mammals are moderately conscious. Conscious organisms are aware of the immediate environment, and depending on sensory feedback, are able to adjust behaviors. In this sense, consciousness is a form of error correction and action modulation, and its adaptive utility is obvious. The ability to react rapidly to constantly and rapidly changing environments is critical to survival.
Many researchers refer to “primary consciousness,” which is most often noted in mammals and birds, and “higher order consciousness,” which is typically associated with humans (and may be minimally present in some apes, elephants, and cetaceans). Primary consciousness revolves around a remembered present and involves episodic memory. Its activation requires an external or environmental stimulus. Higher order consciousness entails introspection and involves both short and long term memory. It is self-cueing and does not require external or environmental activation, though this often occurs. Higher order consciousness also entails causation and subjectivity, which is an awareness of self associated with agency. For most humans, this aspect of consciousness is self-evident and usually manifests as a stable identity. For other species, its presence may be indicated by self-recognition in mirror tests. Chimpanzees, elephants, and dolphins all appear to recognize themselves when presented with mirrors.
Given the central role that consciousness plays in our waking lives, it is not surprising that many researchers locate it in a central part of the brain: the thalamocortical system. The thalamus is medially situated to integrate sensory inputs and motor outputs. It appears to be a kind of switching center, with massive numbers of reciprocal relay cells engaged in recursive and parallel signaling. Gerald Edelman calls these relay signals “re-entrant interactions” that take place in the thalamocortical “dynamic core.” Significantly, brain wave activity in this core fluctuates in accordance with attention. Because the thalamus is centrally situated, it mediates between subcortical and neocortical processes. Its location, therefore, probably serves as an integrating area for the normally stable platform we call “consciousness.”
When we sleep, we are not conscious. This does not mean, however, that being awake ensures “full” consciousness. While awake, we can experience major fluctuations in consciousness, ranging from reverie (day-dreaming) to delusion. The latter can be caused by pyschotropic drugs or pathology (e.g., schizophrenia). Meditation can result in altered states of consciousness, as can fasting, other forms of deprivation, and physical activities or exertions. There are many ways to induce such fluctuations.
Lewis-Williams argues that these fluctuations (“altered states of consciousness”) give rise to the supernatural thinking on which all religions are built. I will be evaluating his claim — and others in his book — in the next few posts.