Definition excerpted with permission from Ginger, Serge International Glossary of Gestalt Psychotherapy (Seven languages including English. Order from FORGE at 183 rue Lecourbe; 75015 Paris, France) Paperback 1995.
-(from the Latin ad-gredere, to go towards the other; opposite re-gredere, to draw back, to go backwards; similar to pro-gredere, to progress, to go forward). For Perls, as for contemporary ethologists, aggression is a life instinct and not a 'death instinct', as it was for Freud; necessary for the active assimilation of the external world in order to avoid introjections: first you have to bite the apple and chew it (destroy it) before you can digest it.
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