In 1879 G. H. Lewes described the state of current British mental science. There were, he maintained, three main ‘schools’ of psychology. The first of these Lewes called the ‘ontological’ school; its members traced their lineage to Thomas Reid and to the common sense philosophers of the early nineteenth century, especially Dugald Stewart and William Hamilton. The second school was the ‘empirical’, which stood in the tradition of Locke, Berkeley, Hume, Condillac, Hartley, and James Mill. The ontologists and the empiricists (...) differed in their theories of knowledge: the former held that certain beliefs were native to the mind; the latter that all ideas originated, mediately or immediately, from experience. However, both schools agreed on the object of psychological enquiry. They ‘quietly ignore the complex conditions of the living organism, and treat mental facts simply as the manifestations of a Psychical Principle’. Further, the ontological and empiricist schools concurred on the means by which this principle should be studied; both made introspection the ‘exclusive method of research’. (shrink)