Congruity Theory, proposed by Osgood and Tannenbaum (1955), belongs to the broader family of consistency-based theories in social psychology, alongside Heider’s Balance Theory (1946) and Festinger’s Cognitive Dissonance Theory (1957). These approaches are grounded in the assumption that individuals are motivated to maintain coherence among their cognitions, attitudes, and evaluations.

Heider (1946) suggested that individuals seek balanced cognitive relations between themselves, other people, and objects. Festinger (1957) further showed that inconsistencies between cognitions generate psychological discomfort, referred to as cognitive dissonance, which motivates individuals to restore consistency by modifying attitudes, beliefs, or behaviors. As a result, individuals tend to favor relatively stable and internally coherent cognitive structures over time (Festinger, 1957, 1962).

Building on these foundations, Osgood and Tannenbaum (1955) focused specifically on attitude change in persuasive communication. Congruity Theory explains how evaluations of a source and evaluations of an associated object or message are interdependent. When a person holds incongruent attitudes, for example a positive evaluation of a message combined with a negative evaluation of its source, this imbalance produces psychological tension. Attitude change then occurs toward greater congruence, through partial adjustments to both evaluations.

Congruity Theory is closely related to self-consistency perspectives, including Korman’s (1976) application of consistency principles to work behavior. From this perspective, individuals strive to behave in ways that are consistent with their self-concept, reinforcing the central role of congruence in evaluative processes.

In consumer research, these consistency mechanisms have been applied to self-product relationships. Consumers tend to evaluate products and brands more favorably when the perceived image of the product is congruent with their actual or ideal self-concept, a phenomenon commonly referred to as self-congruence (Graeff, 1996; Fennis & Pruyn, 2007).

In social media contexts, consumers actively select the influencers they follow, often because these figures reflect shared values, interests, or aspirational identities (Boerman, 2020). This selection process establishes a positive cognitive relationship between the consumer and the influencer. When an influencer endorses a product that is perceived as consistent with their image, congruence is maintained across the evaluations of the influencer and the product (Casaló et al., 2020). Conversely, perceived incongruence between the influencer and the promoted product may disrupt this cognitive alignment and lead to less favorable evaluations (Breves et al., 2019).

References

Boerman, S. C. (2020). The effects of the standardized Instagram disclosure for micro and meso influencers. Computers in Human Behavior, 103, 199-207.

Breves, P. L., Liebers, N., Abt, M., & Kunze, A. (2019). The perceived fit between instagram influencers and the endorsed brand: How influencer–brand fit affects source credibility and persuasive effectiveness. Journal of Advertising Research, 59(4), 440-454.

Casaló, L. V., Flavián, C., & Ibáñez-Sánchez, S. (2020). Influencers on Instagram: Antecedents and consequences of opinion leadership. Journal of Business Research, 117, 510-519.

Fennis, B. M., & Pruyn, A. T. H. (2007). You are what you wear: Brand personality influences on consumer impression formation. Journal of Business Research, 60(6), 634-639.

Festinger, L. (1957). A theory of cognitive dissonance. Stanford University Press.

Festinger, L. (1962). Cognitive dissonance. Scientific American, 207(4), 93-102.

Graeff, T. R. (1996). Image congruence effects on product evaluations: The role of self‐monitoring and public/private consumption. Psychology & Marketing, 13(5), 481-499.

Heider, F. (1946). Attitudes and cognitive organization. The Journal of Psychology, 21(1), 107-112.

Korman, A. K. (1976). Hypothesis of work behavior revisited and an extension. Academy of Management Review, 1(1), 50-63.