goals of developmental science are to describe, explain and optimise
within-person change and between-person differences in within-person change across
the life span (Baltes, Reese, & Nesselroade, 1977; Lerner, 2012). The third
foci of the field, optimization, the application of developmental science
descriptions and explanations to policies or programmes, has been often been
split off from these first two foci- yet almost four decades ago, Urie
Bronfenbrenner operationalized a theory that integrated all three loci of human
development. Bronfenbrenner (2001) defined his bioecological theory as “an
evolving theoretical system for the scientific study of human development over
time” (p. 6963- 6964). This conceptualisation of human development is a four-
element model, involving the synergistic interconnections among proximal
processes, person characteristics, context and time (PPCT). At its core, it models
an active person enmeshed in an active, dynamic, social- ecological system
emphasising developmental change and the individual context.

A Contextualist Framework

tiers of the PPCT model is nested upon one of the three main worldviews,
contextualism as stated by Pepper (1942). As Pepper (1942) discussed, within
psychology, these paradigms are mechanism, organicism, and contextualism. Mechanists
believe that in order to comprehend something it must be broken down into its
simplest form. In addition that accept the idea of environmental, genetic,
biological and physiological causes, whereas organicists and contextualists
postulate that causes are formal, which emanate from interrelations between
multiple variables. There is, however, also a distinction between organicists
and contextualists that should not be blurred. The former, but not the latter,
hold that there are “final” causes—that is, that there is directionality to
development and that individuals typically go through stages in a given order
(Goldhaber, 2000; Pepper, 1942). Contextualist theories, such as those of
Vygotsky and Bronfenbrenner, have no such universal end point of development in
view; rather, what counts as competent development will vary in part according to
situation-or culture-specific pressures.

person process, context and time model is rooted in the contextualist metaphor
of cognitive change as a concrete historical process (Pepper, 1942). That being
said, dialectical considerations play an important role, in Bronfenbrenner’s
conception of the complex and changing reciprocity in the relations between the
developing individual and the simultaneously changing world. Within this
dialectial or contextualist theory, it is assumed that the source of all
knowledge lies in the continuing interactions between individual and
environment, neither of which can simply impose itself on the other. In keeping
with their contextualist root metaphor, view the resulting knowledge not as an
equilibrated, abstract, content-free structure but as a concrete item in a
population of interrelated concepts, always context-laden and highly subject to
further idiosyncratic contradictions. For the most part, then, development does
not follow a universal, predictable sequence but rather is a partially
unpredictable outcome of interacting changes at several levels – biological,
psychological, sociological, and physical (e.g., Lerner, Skinner, & Sorel1,
1980; Riegel, 1979).



A Pioneer for Naturalistic

of developmental psychology, as it now exists, is the science of the strange
behaviour of children in strange situations with strange adults for the
briefest possible periods of time” (1979, p. 19). This famous quote aptly
captures Bronfenbrenner’s assertion that, empirically, assessments of development
must be conducted with the recognition that contexts are complex, denoted by Bronfenbrenner’s
(2005) notions of the micro-, meso-, exo- and macro-systems). With that said,
the PPCT model has made some of its greatest contributions to human development
research by acting as the impetus behind the reorientation of developmental research
towards context into the family, peer group, school neighbourhood and wider
community and society. Importantly, the PPCT model was not a causal model, and
was not predictive. Rather, Bronfenbrenner advocated empirical testing in
particular instances to see cause in context. He believed that there was
potential relevance of all the factors in his model to be discovered at each
level of social context and encouraged researchers to extricate within an
across the various levels of his framework. Concluding that development is not
as predictable and universal as once thought, he surmised that individuals
cannot necessarily act in ways that benefit all levels and all components of
the context at all times and places (Elder et al., 2015). Thus, one may need to
treat adaption not as a multivariate concept that is determined by the
interaction of multiple factors over time. composed of ordinal or interval
dimensions. He also emphasised acknowledgement of the impact of culture human
development. Understanding and promoting these culturally sensitive adaptive
developmental regulations can provide, as Bronfenbrenner (2005) argued, the knowledge
base for making human beings human.