The sociology of scientific knowledge (SSK) is the study of science as a social activity, especially dealing with "the social conditions and effects of science, and with the social structures and processes of scientific activity." The sociology of scientific ignorance (SSI) is complementary to the sociology of scientific knowledge.For comparison, the sociology of knowledge studies the impact of human knowledge and the prevailing ideas on societies and relations between knowledge and the social context within which it arises. Sociologists of scientific knowledge study the development of a scientific field and attempt to identify points of contingency or interpretative flexibility where ambiguities are present. Such variations may be linked to a variety of political, historical, cultural or economic factors