For most students (and for many established researchers), the highest level at which they have thought about their target phenomenon is the level of the conceptualization or theory. That makes the analysis of theories a good starting point for meta-theoretical reflection. In order to analyze a theory for its underlying assumptions about the nature of people, their contexts, and the meaning of development, however, we have to be clear on how theories fit into the goals of developmental science, and to deeply understand the theories themselves.
Developmental science has three goals: to describe, explain, and optimize human development (Baltes et al., 1977; see Table 2.1). There two target of human development: (1) patterns of normative change and stability and (2) patterns of differential change and stability. Patterns of normative change refer to regular age-graded constellations of intra-individual change, including quantitative changes, often referred to as “trajectories,” and qualitative changes, such as reorganizations or the emergence of new forms. Patterns of normative stability refer to regular age-graded periods of constancy, including quantitative consistency, or flat trajectories, as well as continuity in qualitative organization or functioning. We illustrate what it means to describe, explain, and optimize these kinds of development using examples from the area of children’s motivation for school (Wigfield, Eccles, Schiefele, Roeser, & Davis-Kean, 2006).