Situational strength

Situational strength is defined as cues provided by environmental forces regarding the desirability of potential behaviors. Situational strength is said to result in psychological pressure on the individual to engage in and/or refrain from particular behaviors. A consequence of this psychological pressure to act in a certain way is the likelihood that despite an individual's personality, they will act in a certain manner. As such, when strong situations (situations where situational strength is high) exist, the relationship between personality variables (for example, extraversion, risk-taking behaviors, etc...) and behaviors is reduced, because no matter what the personality of the individual is, they will act in a way dictated by the situation. When weak situations exist, there is less structure and more ambiguity with respect to what behaviors to perform. In sum, situations have the ability to restrict the expression of individual differences in terms of actual behaviors.

An example of a strong situation is a red traffic light. Traffic rules dictate how people are supposed to act when they see a red light, and this influence often prevents people from engaging in behaviors that are consistent with their personality. For example, most people, no matter whether they are daring or cautious, will stop in front of a red traffic light. Therefore, one could not reasonably predict how a person would behave with personality in this situation.

In contrast, an example of a weak situation is a yellow traffic light because the most appropriate course of action is not especially well defined and norms are inconsistent. Thus, individuals who are more daring are likely to speed through the intersection on a yellow light, whereas cautious individuals are likely to stop.

Although it is difficult to formally express when situations restricting individual differences in personality began in psychology, work conducted by Carl Rogers suggested that certain individual differences are mostly likely to manifest themselves in situations where there is psychological freedom and safety, compared to situations where psychological freedom and safety do not exist. Additionally, Stanley Milgram argued that psychological forces of conflict may not be brought into play under diluted conditions. However, recent conceptualization and study of situational strength can be traced back to the work of Walter Mischel. In 1968, Mischel published his classic book, Personality and Assessment, where he argued that personality cannot be studied in a vacuum; instead, the complexity of human behavior and its determinants must be studied from a perspective that accounts for the simultaneous and interactive impact of individual differences and situational characteristics. It is important to note that Mischel did not imply that people show no consistencies in behavior, or that individual differences are unimportant. The major theme was rather that the trait approach to personality was not as sensitive to the influence of situations as it should have been.

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