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This book attempts to take a firm grip on a corner of the slippery issue of consciousness. It is directly related to Roger Penrose's earlier, hugely successful work, The Emperor's New Mind. Although much space is devoted to painstaking replies to the criticisms made of the earlier book, this is not simply a sequel. It contains a number of new ideas, some of which are still being actively debated seven years after the book was first published.

The famous mathematician Euclid is credited with being the first person to axiomatise the geometry of the world we live in  that is, to describe the geometric rules which govern it. Based on these axioms, he proved theorems  some of the earliest uses of proof in the history of mathematics. 