Perception is the apprehension of the relatedness of things with reference to a particular space and time framework. The relatedness of things is revealed through action. As a result of the effectiveness of actions the individual builds a pattern of unconscious assumptions. This assumptive world at any particular time determines the individual's perceptions. Constancy behavior is defined as the attempt to maintain a world which deviates as little as possible from the world one has experienced in the past, which is (...) the only world one knows, and which offers one the best chance of acting effectively. (shrink)