Virulent debates about the nature of consciousness have been going on for centuries; and in general three possible answers have been given; the first is that consciousness is a property of brains, perhaps secreted as the liver secretes bile, often called central state materialism; the second is that consciousness is either itself some spooky extra thing on top of the quotidian things of the world, or is a property of such a spooky extra, substance or Cartesian dualism; the third is that consciousness, or potential for consciousness is a an intrinsic property of everything, or at all information processing systems, panpsychism or property dualism.
Koch, who is a professor of both biology and engineering at the California Institute of Technology recounts his own life journey in the neuroscience of consciousness, including the loss of his childhood Roman Catholic faith, his long time collaboration with Francis Crick the co-discover of DNA in the development of a science of consciousness, through to his own existential (spiritual?) crisis on the death of his own father and his mentor Crick.
Koch takes us through the search for the origins of consciousness in the brain, noting that portions such as the cerebellum, at the back of the brain, can suffer quite extensive damage with severe physical effects without any dimming of consciousness, while even slight damage to tiny areas elsewhere can have profound effects on the phenomenology and nature of consciousness.
Koch‘s view on consciousness is based on the theory of ‘integrated information’ developed by Giulio Tononi, now of the University of Wisconsin:
Koch is now engaged on a project the ultimate aim of which is to find an object measure of the degree of consciousness in a range of organisms, and in human patients with persistent vegetative state, locked-in syndrome, coma etc. It might also give the insights which would us to build a fully conscious computer.
Koch sees a way of envisioning consciousness as a metaphorical crystal in a trillion dimensions. This may be the 21st century version of the soul, but when the underlying physical system disintegrates, the crystal is extinguished. Without some carrier or some mechanism, integrated information can’t exist.
Those who propose some kind of life after death then, would have to propose some kind of mechanism that would allow continued information processing (and presumably acquisition and storage). This ‘psychon’ would then have to be at least as complex as the human brain, a rather large ask. – Peter Rogerson.