The view that the rate of upward mobility in American society has declined seems to be widely held among social scientists. W. Lloyd Warner has commented, for example: "There is strong proof now that the American worker, as well as others, can no longer expect to achieve success with anything like the same probability as did his father and grandfather."1 Discussions of the Horatio Alger tradition of "rags to riches" and "strive and succeed" often refer to it as a myth once applicable to American society but now only an ideological prop to things as they are.2 Even introductory textbooks in sociology frequently assert that there has been a definite decline in the rate of upward movement in the social structure.3
The recent appearance of several substantial studies which suggest that the rate of mobility may not have declined4 and the growing awareness among sociologists of the inadequacy of the available data call for an appraisal of our knowledge concerning possible changes in the rate of upward movement in American society. Only by assembling and collating the facts which are available can we test the prevalent assertions about vertical mobility, see the gaps in our knowledge, and define the direction in which research should be channeled.
Students of social mobility have usually focused their attention upon movement in the occupational hierarchy. Despite difficulties inherent in the use of occupational data, no other type of information is as readily available or as amenable to systematic analysis. . . .
The mass of available evidence demonstrates clearly the existence of a high correlation between occupation and the various criteria of class: prestige, income, wealth, style of life, and power.5 Although there is some disagreement on the relative importance of each of these variables within the total system, there seems ample warrant for concluding that in American society, at least, occupation is probably the most significant, that is, it is more likely to influence other variables than to be influenced by them.6
The analysis of occupational mobility has taken two forms, inferential and direct. Inferential analysis focuses attention upon changes in American society which may affect the rate of mobility. Conclusions about trends are inferred from the facts of institutional, structural, and demographic change.
The second form of mobility analysis seeks to compare directly the social origins and career patterns of members of each class at different times in order to establish the frequency or rate of mobility and to