Talcott Parsons (1902-1979) developed a general social theory called Action theory, based on the methodological principle of Voluntarism and the epistemological principle of analytical realism. The theory attempted to establish a balance between the utilitarian-positivist and hermeneutic-idealistic methodological traditions. For Parsons, voluntarism established a third alternative btwn these two (Wikipedia).
Talcott Parsons (December 13, 1902 – May 8, 1979) was an American sociologist who served on the faculty of Harvard University from 1927 to 1973. Parsons developed a general theory for the study of society called action theory, based on the methodological principle of voluntarism and the epistemological principle of analytical realism.
Functionalists look at family as universal for for fulfilling 6 things: economic production, socialization of children, care of sick, recreation, sexual control, and reproduction which are all necessary for society. They also believe incest taboos create clear lines between the relationship of the family members, forcing them to marry outside their family.
"From all this it follows what the general character of the problem of the development of a body of scientific knowledge is, in so far as it depends on elements internal to science itself.", Talcott Parsons