Ian McGilchrist is a psychiatrist who has written a book on the two sides of the brain. He contends that the left brain does narrow thinking, whereas the right brain looks at the big picture. On Radio 4 this morning he pointed out a dual task evolution gives birds: trying on the one hand to eat a piece of food, and on the other hand trying to avoid being eaten. The first task needs a narrow, analytical view to solve a given task; the second task needs broader vision, and an understanding that something might 'come from nowhere'.
Philosopher A C Grayling has suggested that the state of brain science is not sufficient to prove the scientific case about the function of each hemisphere. And McGilchrist himself admints that in fact both sides of the brain are involved in most thought in highly complex ways. However, McGilchrist's point, apart from the science, is that western culture has spent too long on narrow, logical analysis, and too little time on wide, imaginitive thought.
The book is called 'The Master and His Emissary'. The name comes from a story in Nietzche's writings, in which a wise master trusts an emissary to help rule his kingdom. The emissary, however, becomes contemptuous of his master, and takes over, only to create a tyranny which eventually collapses. McGilchrists suggests that the 'wide-thinking' master is the right hemisphere, and its somewhat grandiose 'narrow-thinking' emissary the left hemisphere. McGilchrist suggests that the history of ideas in the western world show a struggle between the two 'thought types', with the left hemisphere in danger of successfully, but disastrously, usurping the right.
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