Introduction: Prions?; E.Seguin PART I: KNOWLEDGE The Early History of the Protein-Only Hypothesis. Scientific Change and Multidisciplinary Research; M.J.Poulsen & H.Andersen Styles of Scientific Practice and the Prion Controversy; K.Kim Paradigm Change? Explaining the Nature of the TSE Agent in Germany; K.Dressel PART II: DISCOURSE Visualizing Prions, Graphic Representations and the Biography of Prions; J.Segal & E.Francoeur PART III: POLITICS Prion...