If this theory is right, certain kinds of connection between mind and brain are inescapable. Corresponding to memory, for example, there must be some physical modifying of the brain, and mental life must be connected with physical properties of the brain tissue. In fact, if we had more knowledge, the physical and psychological statements would be seen to be merely different ways of saying the same thing. The ancient question of the dependence of mind on brain, or brain on mind, is thus reduced to linguistic convenience.
Source: Bertrand Russell : Mind and Matter (1950?)
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