Kurt Lewin’s Field Theory: a review and Re-evaluation

Defining field theory

The rationale for field theory is Lewin’s belief that all behaviour arises from the psychological forces in a person’s life space and that behavioural change arises from changes to these forces (Cartwright 1952b). Therefore, in order to understand, predict and begin to change a person’s behaviour, it is necessary to take into account everything about the person and his/her perceptual or psychological environment in order to construct the person’s life space (Lewin 1943a). The life space includes only those aspects of the envir- onment that are perceived at some level, either con- sciously or unconsciously, by the individual (M. Lewin 1998). Wheeler (2008, p. 1640) observed that: ‘[the] Life space is the total psychological envir- onment that the person experiences subjectively, although not necessarily consciously’.

Rummel takes a similar view of field theory:

First, it is an emphasis on a person’s subjective perspective. Second, it incorporates the whole that

is subjectively relevant to a person and to organize behavior, goals, needs, desires, intentions, tensions, forces, and cognitive processes into one system. Third, the elements composing this whole are interdependent and stand in dynamic mutual rela- tionship. Fourth, the key to the dynamic nature of this subjective whole is the idea of tension (energy) systems created by needs and discharged by achieving associated goals. Fifth, the dynamic psy- chological construct is that of inner-personal forces, which result from the intensity of personal needs and the valence of associated goals. Sixth, blocked goals can lead to increase in tension and a variety of behavioral and psychological conse- quences. And finally, inner-personal conflict is the result of opposing psychological forces. (Rummel 1975, pp. 43–44)

Therefore, for Lewin (1947b), the field in which a person’s behaviour takes place is an intricate set of symbolic interactions and forces that, depending on their valence (strength), can either reinforce or change their behaviour.

Lewin expressed his theory in the formula:
B  f ( p, e)
That is to say, behaviour B is a function of the inter- action between the person p (or group) and their environment e. (p,e) is also how Lewin defined the individual or group’s life space (Marrow 1969). He recognized that individuals and groups do not inhabit just one life space, but have separate life spaces for work, home and other activities. He maintained that, if one could identify, plot and establish the potency of the forces in a person’s life space, it would be possible not only to understand why individuals, groups and even entire organizations act as they do, but also what forces would need to be diminished or strengthened in order to bring about behavioural change.
Lewin saw field theory as a way of combining scientific rigour and practical relevance by offering a rigorous, theory-based method for analysing behav- iour, and a practical approach to changing behaviour by allowing individuals to understand their actions better. Lewin saw behaviour as the product of the environment and the way in which individuals inter- pret external stimuli. Field theory allows an indi- vidual or group to map out, and thus learn to understand, the totality and complexity of the life space in which their behaviour takes place, and appreciate how the forces that comprise their life space can be changed or reinterpreted in order to

Figure 1. A Lewinian life space

modify their own behaviour. Consequently, for Lewin, change was a learning process; he believed that successful behavioural change could only be achieved if individuals and groups could be helped to understand and reflect on the forces that impinge on their lives (Lewin 1942).

Given what was involved in this learning process, Lewin saw behavioural change as being a slow endeavour. However, he did recognize that, under certain circumstances, such as a personal, organiza- tional or societal crisis, the various forces in the life space can shift quickly and radically. In such cases, established routines and behaviours break down, and the status quo is no longer viable. New patterns of activity can rapidly emerge, and a new behavioural equilibrium or ‘quasi-stationary equilibrium’ is formed (Lewin 1947a).
Figure 1 shows a simplified example of a Lewin- ian life space. Each of the segments within the life space represents a different psychological force. Lewin argued that it is not sufficient to identify one or two of the forces that impinge on the individual or group, but that all the forces, and how they relate to and interact with each other, have to be taken into account (Cartwright 1952a; Lewin 1939a, 1944). Therefore, the life space presents a holistic view of the individual and their situation. As all parts of the life space are interdependent, changes to one part of the field are likely to lead to changes in the whole field. This is not just because of the interdependent nature of the psychological forces, but also because the life space as a whole is different from the sum of the individual forces that impinge on a person. As Lewin (1939a, p. 8) put it: any dynamical whole has properties of its own. The whole might be symmet- ric in spite of its parts being asymmetric, a whole might be unstable in spite of its parts being stable in themselves.’
The individual forces in the field are themselves subject to change and, as they are constantly interact- ing with each other, they create a field that is in a continuous state of dynamic equilibrium (Deutsch 1968). As Lewin (1947a, p. 199) put it: ‘Change and constancy are relative concepts; [individual and] group life is never without change, merely differences in the amount and type of change exist.’ This is why Lewin used the term ‘quasi-stationary equilibrium’ to indicate that, while there might be a consistent rhythm and pattern to the behaviour and processes of an individual or group, these tended to fluctuate con- stantly owing to changes in the forces or circum- stances that impinge on the individual or group.