The Spread Mind: Why Consciousness and the World Are One
by Riccardo Manzotti
(O/R Books, £17)

EVEN readers familiar with key concepts in neuroscience and cognitive psychology are likely to find The Spread Mind a tricky read.

Not because Riccardo Manzotti is a poor communicator of complex material or that he lacks commitment to widening access to the science of consciousness but because the idea at the heart of his latest book is so profoundly subversive of scientific orthodoxy it demands careful reconsideration of experimental evidence and personal experience.

Experience is key to Manzotti’s theory of consciousness. Conscious experience is an aspect of nature, he suggests, and has no special status as a simulation or reconstruction of reality.

This means it is not merely a special property emerging from neural activity but is as much a part of the physical world as the objects with which our bodies interact.

So, he says, work in neuroscience and cognition should focus on the physical foundations of human experience rather than searching for “mysterious mental properties.” Manzotti proposes a wholesale rejection of the philosophy of Rene Descartes, in which the universe consists of both physical matter and non-physical stuff, such as the mind or soul.

He asserts that the Cartesian view arose from a specific interpretation of the empirical data available in the 17th century and that a reassessment of Descartes’s data — and evidence gathered in the last 400 years — is long overdue and his model of conscious experience should be tested against evidence from standard perception, perceptual illusions, dreams, hallucinations and clinical cases.

Dreams and hallucinations are often cited as evidence for cognitive processes divorced from the material world, but Manzotti asserts brain activity is totally based in the world of physical objects. He sees objects as relative, temporal and “spread” — our interaction with them happens across time and space.

So, the “non-standard” versions of objects in our dreams and hallucinations are based on real-word encounters with them at some time and at some location. Thus, Manzotti’s model draws on Einstein’s notion of relativity rather than Cartesian dualism.

At times, the book becomes an intellectual white-knuckle ride for the informed general reader, not least when the author explains a series of well-known visual illusions in terms of the difference between absolute and “proxy” dimensions.

But The Spread Mind introduces innovative tools for thinking about thinking. It’s a demanding book but one which has the potential to enrich our understanding of the way we interact with the world and come to understand it.