Mind and world
Henri Bergson criticises “realist” positions in the philosophy of perception, but “realism” denominates what contemporary philosophy terms, more specifically, indirect realism. He presents the operation of the body in perception as, in principle, wholly independent of memory, mind and any spiritual principle. The body has afferent, “centripetal” nerves, and these seem to transmit movement from the external world into the brain, but it also has efferent, “centrifugal” nerves that transmit movement from the brain to the extremities of the body. Conscious life and conscious perception arrive with the increasing complication of motor mechanisms established in the body, which allow for a wider variety of responses to situations, for more physiological indetermination, and for memory and thus mind to intervene. Thus understood, Bergson urges us to recognise that the “book of nature”, to use the age-old metaphor, is not at bottom a picture-book, and that it cannot be grasped adequately by the faculty of the mind that is the imagination.