In Chapter 2, Michael Shanahan, Jaan Valsiner, and Gilbert Gottlieb address the usefulness of common concepts for describing human development and discuss their transposition across psychobiology, psychology, and sociology. The concepts are identified as theoretical principles of human development that arise out of “an epigenetic characterization of development as an emergent coactional hierarchical system” (Gottleib 1991a, p. 7). We interpret their statements as proposing that development should be viewed in terms of a systemic structure with bidirectional relationships between vertical and horizontal levels, occurring in social and personal time, and changing probabilistically, where changes are manifested in coactional coordinated patterns across levels of human functioning. Further, we see their final principle as a different kind of statement, not defining development as such, but rather identifying developmentalists' studies of change as activities located within a disciplinary domain and influenced by intellectual and social criteria.

Shanahan et al. are interested in establishing a foundation for interdisciplinary communication and multidisciplinary research in developmental science. Their analysis of the across–discipline parallelism and transposability of developmentally significant concepts is a timely piece of metatheoretical research. Wielding the analytic tool of examining the underlying structure of theories, the authors demonstrate that the developmental principles can be employed as heuristic definitions to identify commonalities of use in the three disciplines.