Human development, or more accurately child development, was often studied in the first several decades of this century within university institutes – for example, at Iowa, Minnesota, and Berkeley. Although these centers originally took a multidisciplinary approach, the pluralistic perspective began to erode by the 1950s and was eventually replaced by a single view of development, the psychological (L. P. Lipsitt, pers. comm., December 1979; D. S. Palermo, pers. comm., August 1980; see also Hartup, 1978). The 1970s were marked by calls for a return to interdisciplinary integration (e.g., Brim & Kagan, 1980; Bronfenbrenner, 1977; Burgess & Huston, 1979; Hill & Mattessich, 1979; Lerner & Spanier, 1978; Petrinovich, 1979; Riley, 1979; Sarbin, 1977), calls motivated primarily by instances of failure to confirm some key hypotheses of developmental psychological analysis.

A case in point involves attempts to use a biological model of growth, one based on an idealized maturational (organismic) conception of development, to account for data from the adult and aged years (Baltes, et al., 1980; Baltes & Schaie, 1973). According to this type of organismic conception, the adult and aged years are periods of decline. However, much of the data regarding age changes (e.g., in intellectual performance) during these life periods turned out to be inconsistent with this paradigm. For example, pertinent data sets revealed increasingly greater differences in individual change: As people grow older, the differences between them apparently increase (Baltes, 1979a; Baltes & Schaie, 1974, 1976; Schaie, Labouvie, & Buech, 1973).