This article investigates the relationship between two influential intellectual schools in late 19th century Britain, namely social evolutionary theories and British Idealism, by focusing on the work of D.G. Ritchie who drew inspiration from both sources. In particular, it argues that Ritchie's work can best be understood as an attempt to overcome certain metaphysical problems in the work of his teacher, T.H. Green, by integrating an Idealist account of social development with a Darwinian one, and analyses the effects this synthesis (...) has for his social and political thought. Ritchie's approach is also set in the context of developments in Victorian evolutionary theory and is contrasted with that of other influential Idealists, notably Bernard Bosanquet. More widely, it is claimed that examining Ritchie's synthesis sheds light on the degree to which the labels “idealist” and “positivist” can be reliably used in the later Victorian period, in the areas of both scientific and social investigation. (shrink)