Since human beings started to reflect on the nature of their own development and psychological functioning, they have conceived the relationship between the individual organism and his or her environment in diverse and multiple ways. From psychology's first systematic efforts to organize itself into a scientific domain, its focus of investigation has fluctuated from the organism to the environment and vice versa, with different emphases on the role played by specific aspects of either the individual or the environment in the configuration of the phenomena. As Jonathan Tudge, Jacquelyn Gray, and Diane Hogan point out in their inclusive historical account of ecological thought in Chapter 3, very early theoretical psychologists realized that a more adequate way to approach the complexities of psychological events would require the assumption of interdependent relationships linking the individual and the environment. Though from different theoretical perspectives, that is what can be found, for example, in Dewey (1896), Baldwin (1895, 1906), Mead (1912, 1913, 1934), Vygotsky (1929,1978), and Lewin (1933,1939). The point I propose to discuss here is that the sharing of some basic assumptions (or even concepts), as we can find in these authors, does not necessarily imply further theoretical similarities or complementarity, as Tudge et al. suggest when analyzing Gibson's and Bronfenbrenner's contributions to psychology.

The utilization of the same “umbrella” terminology (Valsiner, 1994a) and the fact that Gibson concentrates his analysis on the physical world, while Bronfenbrenner emphasizes the social dimensions of the environment, may constitute an appealing suggestion to complementarity.