This book provides a contextual study of the development of Alfred Marshall’s thinking during the early years of his apprenticeship in the Cambridge moral sciences. Marshall’s thought is situated in a crisis of academic liberal thinking that occurred in the late 1860s. His crisis of faith is shown to have formed part of his wider philosophical development, which saw him supplementing Anglican thought and mechanistic psychology with Hegel’s Philosophy of History. This philosophical background informed Marshall’s early reformulation of value theory and his subsequent wide-ranging reinterpretation of political economy as a whole. The book concludes with the suggestion that Marshall’s mature economic science was conceived by him as but one part of a wider, neo-Hegelian, social philosophy.