Like Koffka, Kurt Lewin studied with Stumpf. Although part of the general Gestalt movement, Lewin is best known for his field theory. Using geometry’s terms and Gestalt ideas, he held that people live in a psychological life space.
At the center of this field in the individual, who is surrounded by concentric circles of influence. The inner field is inner-personal, and the outer part is perceptual-motor. Behavior is a function of one’s life space (how you perceive the world).
According to Lewin, life space can be subdivided into regions. The boundaries between these regions can vary in firmness-weakness and nearness-remoteness. The topology of the fields is different for each individual but vectors of psychic force can describe an individual’s wants and fears.
For Lewin, there are levels of reality. Each person seeks to resolve the disequilibrium (tension) between their inner self and the outside environment. It is possible to move from region to region (locomotion) along pathways in those regions (hodos). But when a goal is obstructed (a barrier), positive valences grow stronger (we want what we can’t have).
Needs give rise to tension which are a particular valence (positive or negative attraction). When two positive valences are present, the person experiences an approach-approach conflict (i.e., must choose between two equally attractive alternatives). When the valences are negative, the result is an avoidance-avoidance conflict (i.e., two equally unattractive alternatives. Naturally, the most difficult conflict is when we want and don’t the same thing (an approach-avoidance conflict).