“The soul is only the thinking part of the body, and with the body it passes away. When death comes, the farce is over, therefore let us take our pleasure while we can.”- Julien Offray De La Mettrie, 1709-1751; French physician and philosopher.
The third traditional feature of a soul is consciousness, perhaps the greatest mystery of human existence. In his course on consciousness1, Daniel Robinson emphasizes consciousness as sui generis or unlike anything else and requiring science not yet available. It involves a difference between mere registering of an event as a machine can do and knowledge of it. It is a raw awareness and ability to experience, and in its most advanced form, reflexiveness or knowledge of the self. These unique characteristics within otherwise unconscious nature inherently lead us to consideration of a ‘soul.’ Mind adds to simple consciousness further features such as feelings, thoughts, memories, intentions, and so forth.
Robinson notes that typical philosophy of mind favors foundational explanations for the gap between the dynamics of the nervous system and the nature of consciousness – typically some form of causal law. In pure materialism, references to experienced phenomena or qualia (e.g. the color “red”) are just states of the brain. There are problems with this thesis, for example causation usually involves antecedent-consequent events to be of a similar type (e.g. billiard balls striking each other) which does not apply here. It is philosophically and scientifically difficult to see how mental activities lead to physical actions that realize mental purposes, and if mind states are just ‘states of the brain,’ mental acts do not seem to be physicalistically intelligible. People act for reasons not due to causes.
Alternatively if mental activities are ontologically identical to brain states, then relevant features should be interchangeable in linguistic use (Liebniz’s criterion). However as an example all of us know the mental state of ‘pain’, but most of us know very little of the physical basis for it, and regardless of the brain state the neuroscientist pinpoints as ‘pain,’ we would still not deny the authoritative claim of a person to be experiencing pain in the absence of the correlating brain state.
Physicalists revert to modifications: (1) anomalous monism – how mental events and processes induce physical events precludes reduction to scientific terms, (2) supervenience theory – mental states arise from and depend on physical states just as a wood table supervenes on molecules and atoms (e.g. Donald Davidson), (3) proclamations that current physics and understanding of matter is too limited to explain consciousness (e.g. Roger Penrose), (4) default to quantum physics- the brain at the quantum level is an informational system where the mental and material merge (e.g. David Bohm). However Robinson seems to believe that all variations of monism are inadequate, and intuitively we all know mental life and consciousness are fundamentally different from physical states of the brain.
Each of us must reflect deeply on this difficult area of philosophy, but it seems to me the universal history of the bodily death of others as the end of demonstrable mental activity, the consistency of neuroscientific explanation of mind states, and my direct experience of the dependence of my mental life on my physical being (brain) invariably directs me to the monist school. Nonetheless, Robinson’s intuition of the lingering gap suggests an emergent quality of the brain as consciousness which we should incorporate into our revision of the soul.
1Daniel N. Robinson, Consciousness and Its Implications, Lectures 7-8. The Teaching Company, 2007