Contents: Introduction: 'We will not anticipate the past, our retrospection will now be all to the future'; Part 1 Natural Philosophy/Science Identity Issues: Getting the game right: some plain words on the identity and invention of science; How the Principia got its name; Decentering the 'big picture': The Origins of Modern Science and the modern origins of science (with Perry Williams). Part 2 The Identity of 'Medieval Science': Science and religion in the 13th century revisited: the making of St Francis the proto-ecologist, part 1: creature not nature; Science and religion in the 13th century revisited: the making of St Francis the proto-ecologist, part 2: nature not creature. Part 3 The Identity of Particular Investigative Projects: Aristotle's animal books: ethology, biology, anatomy, or philosophy?; Paracelsus fat and thin: thoughts on reputations and realities; Thomas Sydenham: epidemics, experiment and the 'good old cause'. Part 4 Disease Identity: Transforming plague: the laboratory and the identity of infectious disease; Identifying disease in the past: cutting the Gordian Knot; Index.