It was perhaps only the youthful optimism of a new science that allowed Kurt Lewin and his colleagues to believe that they had within their grasp the key elements of a "field theory of the social sciences." Social psychology made great strides in 1930s and 1940s. Lewin and Lippitt (1938) seemed to have demonstrated in the laboratory the inherent superiority of democracy over autocracy. Lewin (1948) provided a theoretical framework for resolving social conflicts, and after his death his colleagues quickly shaped his legacy into a social scientific theory (Lewin, 1951). How could they resist? The physicists had just announced developments that shook the foundations of Newtonian physics. It was expected that Einstein, safely ensconced in the Institute for Advanced Studies, would any day announce the "unified field theory" that would once again make the physical world an orderly place. Could they ask less of the social sciences?

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