In Gestalt psychology and social psychology, field theory is a theory that examines patterns of interaction between the individual and the total field, or environment. The concept first made its appearance in psychology with roots in the holistic perspective of Gestalt theories. It was developed by Kurt Lewin, a Gestalt psychologist, in the 1940s.

This field theory can be expressed by a Lewin's equation: , meaning that behavior B is a function of the person p and their cultural environment e.

History Early philosophers believed the body to have a rational, inner nature that helped guide our thoughts and bodies. This intuitive force, our soul, was viewed as having supreme control over our entire being. However, this view changed during the intellectual revolution of the 17th century. The mind versus the body was a forever evolving concept that received great attention from the likes of Descartes, Locke and Kant. From once believing that the mind and body interact, to thinking the mind is completely separate from the body, rationalist and empirical views were deeply rooted in the understanding of this phenomenon. Field Theory emerged when Lewin considered a person's behavior to consist of many different interactions. He believed people to have dynamic thoughts, forces, and emotions that shifted their behavior to reflect their present state.

Overview of Kurt Lewin's influences Kurt Lewin was born in Germany in 1890. He originally wanted to pursue behaviorism, but later found an interest in Gestalt psychology while volunteering in the German army in 1914. He went on to work at the Psychological Institute in the University of Berlin after World War 1. There he worked with two of the founders of gestalt psychology, Max Wertheimer and Wolfgang Köhler. When Lewin moved to the US, he had become more involved with real world issues and the need to understand and change human behavior. His desire and personal involvement with gestalt psychology led to the development of his field theory. Lewin's field theory emphasized interpersonal conflict, individual personalities, and situational variables. He proposed that behavior is the result of the individual and their environment. In viewing a person's social environment and its effect on their dynamic field, Lewin also found that a person's psychological state influences their social field.

Drawing from both mathematics and physics, Lewin took the concept of the field, the focus of one's experiences, personal needs, and topography to map spatial relationships. Lewin created a field theory rule that says analysis can only start with the situation represented as a whole, so in order for change to take place, the entire situation must be considered. There seems to be a repetition of people having the same unsuccessful attempts to grow and develop themselves and field theory draws the conclusion that this repetition comes from forces within our fields. To display this psychological field, Lewin constructed "topological maps" that showed inter-related areas and indicated the directions of people's goals.

Influence of Gestalt psychology on field theory From the beginning Gestalt theory was psychologist Carl Stumpf's emphasis that a study in behavior should focus on the immediate experience of the agent. Stumpf along with his students, notably Wertheimer and Köhler, went on to develop the school of thought known as Gestalt psychology at the Berlin School of Psychology.

Many of the principles of Gestalt psychology emerged to challenge the dominant behaviorist view of the time. What underlie behaviorism was what Wertheimer called the “mosaic thesis” of perception and experience where the relation between elements are seen as “associations” without real consideration of the content of the elements. Under this view learned behavior is initially acquired by chance. Yet even when, through chance, an animal acts in a way that leads them closer to their goal, they do not realize that they are now closer to their objective. In other words, the animal does not act based on understanding of the situation— the sequence of action is strung together by accident and therefore meaningless. Therefore, behaviorism predicts a “continuous transition between random and useful behavior”. Interestingly, rat mazes used in behaviorist experiments were designed such it was impossible to obtain a survey of the entire layout, a situation rarely found in nature.

In contrast with this view of behavior as random associations was Köhler's argument of the central role that comprehension has in shaping behavior. Köhler argues that a subject (animal or person) goes through a distinct shift in the direction of their behavior when they suddenly gain insight in the form of perceiving the entire picture of a situation.

Furthermore, fields are not just ways of succinctly describing complex data and making prediction from the observer's perspective but is also something that is felt by the actors. We feel physically drawn towards or away from the object that anchors a field of force. Köhler gives the example of when an animal moves closer to a desired object, they may be drawn to the object in a way that prevents them from moving further away from the object to circumvent an intervening obstacle. Another example that he gives is when a nice boss avoids eye contact when delivering criticism to an employee.

Influence of physics on field theory

The principles of Lewin's field theory is connected with his call for psychology to shift from an Aristotelian view of science to a Galilean one. While both views have historically informed physics, the first view is associated with Medieval physics while the latter view has played an influential role in shaping modern physics. Aristotelian physics understands objects through classification— it argues that the category of an object captures its essence and determines its behavior. The construction of these categories are shaped by normative ethics, with categories carrying dichotomous connotations of good and bad. Lewin argues that the influence of this mode of thinking on psychology can be seen where behaviors can be classified as either normal or pathological, and feelings are classified as pleasant or unpleasant. Associated with classification is the practice of studying discrete substances rather than relational dynamics. In psychology, this is reflected in the practice of studying different aspects of psychology such as “memory, intelligence and impulse” separate from one another.

On the other hand, in contrast with categorical thinking, Galilean physics emphasizes structural and relational thinking and understanding elements based on the functional role they play. Understanding reality through its dynamic and continuous processes replace absolute and rigid categories. Galilean physics also posits the existence of universal laws that govern the physical world.

This underlies what Lewin calls the “conditional-genetic” approach of explaining causation, which is central to his field theory. In contrast with the Aristotelian descriptive approach which would attribute different causations to planets orbiting, objects falling and pendulum oscillating given their different surface-level appearance (what Lewin describes as their “phenotypic” presentation), a conditional-genetic approach would recognize these phenomena as “various expressions of the same law”.

Lewin points out that the use of mathematical quantification is not a fundamental difference between the Aristotelian and Galilean view since Aristotelian physics can also be represented mathematically. The impulse to quantify in modern physics can be better attributed to the desire to understand “concrete particular cases” in a world governed by universal laws. Overall, Lewin calls for psychology to follow the direction of modern physics towards “a transition from an abstract classificatory procedure to an essentially concrete constructive model”.

Main principles

The life space The main idea is that an individual's behavior at a given moment is manifested through the interconnected factors that make up the current "life space" or "psychological field." So a person's life space is the combination of all the factors that influence the person's behavior at any time. Behavior can be expressed as a function of the life space B=ƒ(LS). Furthermore, the interaction between the person (P) and the environment (E) constitute life space. Therefore, in symbolic expression, B=ƒ(LS)=F(P,E).

The environment (E) in a person's life space has its basis in the objective physical world that the actor is situated in. However the actual representation and organization of the physical world in their life space is mediated by the subjective experience of the person (P). At the same time, the environment also shapes the person. Field theory holds that behavior (B) must be derived from a totality interconnected factors. Furthermore, behavior depends on the present field rather than on the past or the future.

The relation between person and environment represents the situation at a given moment. Therefore, behavior can also be understood as a function of the entire situation that a person is in. To understand behavior therefore involves capturing all aspects of the situation, which includes the physical, social and psychological situation.

Physical situation The physical situation includes the person's immediate physical environment as well as the larger geographical environment that they are situated in. Factors in their immediate environment can include objects in the environment that a person consciously perceives, but can also include familiar objects that are outside of one's immediate field of vision, for example a calendar that is hung on the wall behind the person or a building outside their window. The larger environment can encompass the location of the house, city or country that the person is in. The physical environment can impose physical barriers that constraints a person's movement, as in the case of Jewish ghettos that many European Jews were confined to during and prior to WWII.

Social situation

The social situation may include the person's social relations or social position in society, including their occupation. It can also include social factors at the present moment, including ones that are not at the forefront of the actor's awareness at the moment. For example, a child playing in the backyard behaves differently depending on whether the mother is at home, even if they are not constantly conscious of this. Another example would be the general social atmosphere (e.g. friendliness or tension) which one may not consciously perceive at the moment and only become aware of when it changes. Lewin's research has identified leadership style as an influential factor shaping the atmosphere of a group. Experimental psychology studies have shown the formation of aspiration, the driving factor of actions and expressions (behavior), is directly influenced by the presence or absence of certain individuals within one's life space.

Social interaction can be represented as the conjoining of multiple individuals’ life spaces. An example of this is when two people's experience of a situation can become one when they converse together. This does not happen if the two people do not interact with each other, such as being in the same room but not talking to each other. This combined space can be "built" up as the two people share more ideas and create a more complex life-space together.Parlet, Malcolm (1991). "Reflections on Field Theory". The British Gestalt Journal 1: 68–91. Retrieved 31 October 2014

Psychological situation

Lastly, the psychological situation may encompass the actor's personality, “fears, thoughts, ideals and daydreams”, and the content and degree of their aspirations.