If observed facts of undoubted accuracy will not fit any of the alternatives it leaves open, the system itself is in need of reconstruction.

Sociology should... be thought of as a science of action-of the ultimate common value element in its relations to the other elements of action.

A scientifically unimportant discovery is one which, however true and however interesting for other reasons, has no consequences for a system of theory with which scientists in that field are concerned.

The implications of these considerations justify the statement that all empirically verifiable knowledge even the commonsense knowledge of everyday life - involves implicitly, if not explicitly, systematic theory in this sense.

The functions of the family in a highly differentiated society are not to be interpreted as functions directly on behalf of the society, but on behalf of personality.

If observed facts of undoubted accuracy will not fit any of the alternatives it leaves open, the system itself is in need of reconstruction.

Theory not only formulates what we know but also tells us what we want to know, that is, the questions to which an answer is needed.