Over several decades, appraisal theory has emerged as a prominent theoretical framework explaining the elicitation and differentiation of emotions, and has stimulated a great deal of theorising and empirical research. Despite the large amount of research in this area, there are many aspects of appraisal theory and research that remain unclear or problematic. In this review, we identify a common assumption of many appraisal theories-the fixed appraisal set-and argue that this assumption, combined with a lack of explicit theorising about the predicted relationship between appraisals and emotions, leads to a lack of clarity in both appraisal models and the empirical testing of those models. We recommend that appraisal theorists move in a direction already taken by a small number of theorists, and adopt the starting assumption of a variable appraisal set. We further suggest that theories of concepts and categorisation may inform theorising about appraisal-emotion relationships.
Keywords: Cognitive appraisal; appraisal theory; categorisation; emotional responses; emotions.