society. In Znaniecki's culturalist perspective, sociology is a study of culture (though it is not the study of culture, as Znaniecki recognized that other social sciences also study culture). His definition of sociology has been described as that of "a cultural science whose function is to study systems of social interaction based upon patterns of values and norms of behaviour, through the use of the humanistic coefficient", or more simply, "the investigation of organized, interdependent interaction among human beings." The part of the culture that sociology focused on was that of social relation or interaction. Znaniecki saw culture as a field separate from nature, but also from individuals' perceptions. The essence of culture is socially constructed objects. He was one of the first sociologists to begin analyzing personal documents such as letters, autobiographies, diaries, and the like. He considered the analysis of such documents an important part of the humanistic-coefficient method. Znaniecki saw sociology as an objective, inductive and generalizing science. According to Szacki, Znaniecki viewed sociology as a nomothetic science that should be able to use a methodology similar to that of the natural sciences (however, Znaniecki's daughter Helena Znaniecki Lopata, in her introduction to Social Relations and Social Roles, contradicts Szacki, writing that, for Znaniecki, sociology was a science "whose subject matter calls for a method different from that of the natural sciences."). In 1934 he formulated the principle of analytic induction, designed to identify universal propositions and causal laws. He contrasted it with enumerative research, which provided mere correlations and could not account for exceptions in statistical relationships. He was also critical of the statistical method, which he did not see as very useful. In addition to the science of sociology, Znaniecki was also deeply interested in the larger field of the sociology of science. He analyzed the social roles of scientists, and the concept of a school of thought. Four social systems According to Znaniecki, sociology can be divided into the study of four dynamic social systems: social action theory, social relation theory, social actors theory, and social groups theory. Znaniecki saw social actions as the foundation of a society, as they give rise to more complex social relations, and he saw this theory as the foundation of all the others. Unlike Max Weber, he did not believe that everything can be reduced to social actions; he was also quite skeptical of any insights coming from