The scientific habilitation of the anonymous, intimate life-history document as a source for the study of culture was especially the work of William I. Thomas. He and Florian Znaniecki undertook and completed their remarkable study of _The Polish Peasant in Europe and America_. One volume was devoted to a long autobiography which included the most intimate facts in the life of a Polish immigrant to the United States. The work of Thomas left an abiding stamp on American sociology through the department at the University of Chicago. Franz Boas, dean of American ethnologists, has been keenly interested in the primitive’s story of himself, and has collected and urged the collection of many such documents. Paul Radin published the life-story of a Winnebago chief in 1916. The importance of “the boy’s own story” was early recognized by William Healy in his study of delinquents, and has been extended in every direction. So, in stressing the value of the study of the concrete sequence of individual experience for political science, we are expressing a trend of interest which is already well founded in social science. Our quest for full and intimate histories has led to the exploitation of a relatively new source of material, the case-history records of hospitals. It has led to the application of psychopathological methods to the study of normal volunteers as a control on the inferences drawn from the institutional cases. It has led to a detailed study of the prolonged interview technique as a method of personality study (especially psychoanalysis), and to the formulation of improved methods of investigation. It has led to the statement of a functional theory of the state, a theory which springs directly from the intensive scrutiny of actual life-histories, and the realization of what political forms can mean when seen against the rich background of personal experience.