The relationship between ideas and social and political changes remains one of the major controversial questions in the social sciences. Certain groups, particularly the Marxists and the behaviorists in both psychology and sociology, relegate ideas to a very subordinate rôle. They claim that for the most part changes in ideas are the result of changes in material conditions or other concrete external factors to which men in society must adjust. At the other extreme are certain philosophers, historians, and philosophically inclined political scientists who assign to ideas an outstanding rôle in the development of economic, political, and social institutions.
The controversy is one that has immediate and practical significance, as well as purely scientific importance. If the United States is to achieve a successful adjustment in a world of rapid economic and political change, the country's leaders will need an accurate understanding of the factors behind these changes, and the probable directions of such change. Such understanding cannot be obtained without knowledge of the major factors involved, such as material conditions and abstract ideas, and the relative importance to be attached to each one. Such knowedge is particularly important in assessing changes in the power relationships among America's potential allies and competitors in the modern world. At the present time, if one may judge from the published diaries of our ambassadors, as well as from what is known of the operations of various intelligence agencies that have received a good deal of publicity since the end of the war, there is no general agreement concerning the procedures to be followed in evaluating symbolic and ideological data, such as statements by important foreign leaders, programs of political parties, and the like, as opposed to more concrete data, such as information on natural resources, economic trends, and similar matters.