Concepts in social theory

In my judgment the appropriate line of probing is with regard to the concept. Theory is of value in empirical science only to the extent to which it connects fruitfully with the empirical world. Concepts are the means, and the only means of establishing such connection, for it is the concept that points to the empirical instances about which a theoretical proposal is made. (p. 4)

The clarification of concepts does not come from piling up mountains of research findings. As just one illustration I would point to the hundreds of studies of attitudes and the thousands of items they have yielded; these thousands of items of finding have not contributed one iota of clarification to the concept of attitudes. (p. 5-6)

Herbert Blumer. „What is Wrong with Social Theory.“ American Sociological Review18 (1954): 3-10

Theoretical concepts and conceptions

Thus it seems natural to think of the concept of justice as distinct from the various conceptions of justice and as being specified by the role which these different sets of principles, these different conceptions, have in common. Those who hold different conceptions of justice can, then, still agree that institutions are just when no arbitrary distinctions are made between persons in the assigning of basic rights and duties and when the rules determine a proper balance between competing claims to the advantages of social life.

Rawls, J. (1999). A theory of justice (Revised ed.). Cambridge, MA: Harvard University Press, as quoted in: Jensen, K. B. (2013). Definitive and Sensitizing Conceptualizations of Mediatization. Communication Theory, 23, 203–222