Notes by RBJ on

Shadows of the Mind

by Roger Penrose

First Impressions

The book continues the case against Turing computable AI and for some thesis along the lines that consciousness is to be explained through quantum effects in the brain which was also the topic of his previous book The Emperor's New Mind.

Though on the same basic theme

The book is divided in to two parts. The first part makes the case that consciousness cannot be caused or simulated by Turing Machine computation. The second part seeks scientific explanations of consciousness through quantum mechanics.

Part I - Why We Need New Physics to Understand the Mind

The Non-Computability of Conscious Thought

Consciousness and Computation
Mind and Science
Can Robots Save this Troubled World
The A, B, C, D of computation and conscious thinking.
Four viewpoints are identified as follows:
All thinking is computation; in particular, feelings of conscious awareness are evoked by the carrying out of appropriate computations
Awareness is a feature of the brain's physical action; and whereas any physical action can be simluated computationally, computational simulation cannot by itself evoke awareness.
Appropriate physical action of the brain evokes awareness, but the physical action cannot even be simluated computationally.
Awareness cannot be explained by physical, computational, or any other scientific terms.
The Gödelian case
The case for non-computability in mathematical thought

Part II - What New Physics We Need to Understand the Mind

The Quest for a Non-Computational Physics of Mind

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