Chapter 5: Characterizing Persons: Core Conceptual Issues

Since the early 20th century, the traditional empirical research agenda has aimed to identify basic trait dimensions, investigate the influence of nature and nurture on those differences, and determine their manifestations across various behaviors. This mainstream view, historically supported by thinkers such as Epstein and Cloninger, operates on the conviction that scientific understanding relies entirely on normative measurement, meaning that any statement about an individual's personality is meaningless unless it is based on statistically-guided comparisons with other people. In this model, a raw assessment (Apd) from an instrument like the NEO Personality Inventory is transformed into an interpretable measure, such as a Z-score or T-score, by using population norms—the mean (M.d) and standard deviation (sd.d) of the aggregate group. However, the chapter promotes the concept of interactive measurement as a viable alternative and a potential basis for a necessary paradigm shift. Interactive measurement, echoing the earlier perspectives of Allport and later refined by Cattell and Stern, suggests that a person’s trait standing can be meaningfully characterized based solely on considerations internal to that individual's possible range of scores. In this framework, the individual’s raw assessment is contextualized by comparing it to the absolute minimum and maximum possible scores (A’min and A’max) they could attain under the constraints of the assessment instrument. Empirical investigations strongly favor the interactive model, showing that profiles derived from this method better match the subjective characterizations and direct ratings that lay persons make of themselves, their peers, and their spouses, compared to profiles derived using traditional normative scoring. Conceptually, the chapter argues that interactive considerations are an essential epistemic precondition for normative characterization, asserting that an individual must already have a definable standing along a dimension before any comparison to others can take place. Therefore, the meaning of a characterization is ultimately dependent on the alternative possibilities inherent in the assessment, not solely on population statistics, supporting William Stern’s original call for a focus on knowledge of persons over knowledge of person variables.