Scientific foundations of psychology between person-centered and average-centered methodological approaches

If the state of a science is always seen as a crisis, then its quality can only be inferior because its claims cannot be trusted. Psychology has been in a state of crisis since its modern inception because there has always been a tension between a person-centered approach and an average-centered approach. Each perspective distrusted the findings of the other and considered their results inadmissible. This article therefore attempts to combine these two perspectives in order to pursue the goal of any science, namely, to increase its systematicity through a process of abduction (Hoyningen-Huene, 2013; Witte, 2023). This happens in three areas: the definition of the subject matter of psychology, the measurability of psychological constructs, and the formation of theories. Each of these starting points is chosen to be one of few assumptions, and these two approaches (person-centered and average-centered) are combined with the overarching goal of increasing systematicity. This has substantial methodological consequences, since the path always leads via a process of abduction, and the usual path is almost exclusively controlled by induction. Methodological implementations are proposed, and concrete methods are discussed.