=The Social Sciences.= The American Association of Public Opinion Research (AAOPR) is the professional league of U.S. propagandists and analysts of public opinion; its quarterly, _Public Opinion_, is the key journal in the field. The members of this association are drawn both from the social sciences and from the psychological sciences, ranging from such practical operatives as Dr. George Gallup and Elmo Roper to austere theorists like Professors Nathan Leites and Hadley Cantril. A good argument can be presented to the effect that the skills brought from the social-science into the propaganda field are more valuable once they are employed full time in that field than an attempt to apply political science, or sociology, or economics, each as an individual compartment, to the field of propaganda. There is still no book available with the title _The Politics of Knowledge_,[60] even though the reception, control, prohibition, and dissemination of knowledge is a major factor in all modern governmental processes both in and out of the propaganda field. =Psychology and Related Sciences.= There has been an immense amount of work done by psychologists, much of it classified, on the field of propaganda. Some of this work is refreshing in the extreme and should provide nasty surprises for the Communists in a major war. Other parts are restatements which if translated into operations might or might not prove feasible with the kind of army we Americans have or are likely to have. One of the most conspicuous developments since World War II has been the application by psychologists, sociologists, and persons in related field of _quantifying techniques_. The introduction of rigorous scientific requirements of _number_ into the attempted reportage of propaganda behavior or propaganda results is having a significant effect. Quantification may not obtain everything which its devotees claim for it. There is a wide area of human behavior which is significant to the ordinary person, or even to the expert in descriptive terms, and which loses much of its significance if the descriptive and allusive terms are replaced by measurements, tables, and graphs. There is, however, no danger that quantification will replace description as the sole tool of research in the propaganda field.