Among distinguished sociologists, Talcott Parsons had a powerful influence on sociology after the Second World War, particularly in America, although, being a theorist, he was not in the dominant tradition of US empirical research. As often criticized as supported Parsons' work was at the centre of debate in sociological theories until the mid-1970s. He wrote a great deal, his principal publications being: The Stucture of Social Action (1937); Toward a General Theory of Action (1951) with E. Shils; The Social System (1951); Working Papers in the Theory of Action(1953) with R. F. Bales and E. A. Shils; Economy and Society (1956) with N. Smelser; Social Structure and Personality (1964); Societies; Evolutionary and comparative perspectives (1966) and The System of Modern Societies (1971).
Parsons' aim was nothing less than to provide a conceptual structure for the whole of sociology. His starting point is the theory of social action, the essential feature of which is the relationship between actors and features of their environment, social and natural, to which they give meaning. The most important features of the environment are other people, which suggests further that social interaction, in which actors have to take notice of the actions, wishes and aims of others, should be the focus of inquiry.
In these interactions, norms and values are critical as they regulate and make predictable the behavior of others. Socialization ensures that individuals internalize norms and values as they grow up. Parsons treats personality and social systems as complementary, though in his analysis the latter ultimately determine the former. Talcott Parsons notes that social interaction has a systemic character, hence his use of the term social system. The concept that bridges social action and social system is that of pattern variables.
Talcott Parsons holds that systems of social action tend to equilibrium even if they never actually reach it, and that social change is movement from one state of equilibrium to another. Change in the system is achieved by differentiation and in his later work Parsons used evolutionary theory to describe the progressive changes in society that result from this. A number of criticisms have been levelled at Talcott Parsons: that Parsons gives too much importance to values and norms; that Parsons does not pay enough attention to social conflict; that Parsons is unable to reconcile action theory and system theory, and in effect Parsons sees individual action as structurally determined; that Parsons's functionalism involves teleology.