The Polish Peasant is a monumental achievement, the earliestmajor landmark of American sociological research. Being centrallyconcerned with issues of ethnic identity and ethnic subcultures,it should be of special interest at present when these issueshave again assumed a salience they seemed to have lost for a timesince Thomas's and Znaniecki's days.
The raw materials of the book (which are reported in exhaustivedetail) are derived from life-histories of Polish immigrants toChicago. These materials--personal letters, autobiographies, diaries,and other personal documents--are extremely rich in their peculiarspecificity. The purpose here is not to delve into the documentaryevidence at length, worthwhile task though that would he; rather,my aim is to delineate the ways, sometimes successful, sometimesnot, in which the authors captured the peculiarities of theirdetailed accounts within a net of generalizing abstractions.
Thomas and Znaniecki self-consciously rejected the fallacy thatany science ever consists in the accumulation of facts. "Afact by itself," they wrote, "is already an abstraction.. . . The question is only whether we perform this abstractionmethodologically or not, whether we know what and why we acceptand reject, or simply take uncritically the old abstraction of'common sense.'" Methodical abstraction would allow themto do justice to their material and yet transcend it, thus providinga theoretical frame that could be used on other materials thathad no concrete resemblance to the Polish data they report intheir work.
From Coser, 1977:511-512.