"On Sociology"--extensively revised, updated, and enlarged for this second edition--addresses the current state of the discipline. Looking to unify increasingly disparate areas of theory and research, John Goldthorpe presents a new mainstream for sociology, combining the demonstrated strengths of large-scale quantitative research and the explanatory power of social action theory. The author's wide-ranging mastery, extending over comparative macro-sociology, applications of rational action theory, and philosophical and theoretical debates on causality, to key questions in educational attainment and class analysis and to the history of statistics in the social sciences, make this an essential book for any sociologist. The collection of closely interlinked essays is presented in two volumes. Volume One begins with a series of critical essays that focus on methodological problems in certain styles of sociological work. The underlying theme is the need for recognition of a common "logic of inference" that must underpin qualitative and quantitative work alike. Volume Two illustrates and applies a new mainstream program, addressing various topics in social stratification to highlight different aspects of the integration of research and theory. Volume Two ends with two retrospective essays that place the concerns of "On Sociology" in the context of the history of the discipline in both the United States and Europe.