THE BEHAVIOR SEGMENT.

Although every factor in an event is equally important it may still be said that a psychological event or psychological interbehavior centers about the mutual interaction of stimulus and response functions, represented by the double headed arrow. These functions localized in the responses of organisms and stimulations of things (stimulus objects) become factors in psychological events when organisms and objects become interrelated in a behavioral field. This coming into contact of the object and organism marks the beginning of the interbehavioral history of the two. This contact under specific setting and mediating (M) circumstances eventuates in the building up of response functions by the organism and stimulus functions by the object. This reaction revolution called reactional biography (RB) and stimulus function evolution (SE) may result in the unchanged successive reoccurrence of events or fields in time, or disappear through various interbehavioral conditions. In many instances it is proper to say that the original functions give place to other response and stimulus functions. While in the diagram both the interbehavioral history and the RB and SE lines continue through succeeding psychological events or behavior segments, at least the RB and SE lines should be broken off past the current behavior segment or interbehavioral field or event when particular response and stimulus functions disappear.

For a comprehensive treatment of the behavior segment in particular and interbehavioral psychology in general consult Kantor, Principles of Psychology, N.Y., Knopf, 1924-26; A Survey of the Science of Psychology, Bloomington, Principia Press, 1933; and Preface to Interbehavioral Psychology, Psychol. Record, 1942, 5, 173-193.