Alan McKenzie traces the philosophical traditions of the passions and the modifications to those traditions required by empiricism and developments in physiology. Love, joy, desire, hatred, sorrow, fear and the other passions, McKenzie emphasizes, were to early philosophers, theologians, and scientists distinctly different from what they now appear to be. From this historical grounding, McKenzie turns to the major prose writers of the 18th century. In his analyses of Addison and Steele's "Spectator", Johnson's "Rambler", Gibbon's "Decline and Fall of the Roman Empire" and selected works of Hume and Fielding, McKenzie argues that the 18th century in general, and these writers in particular, attached to the passions just enough abstraction, vividness and complexity to allow them to retain their traditional semantic force in an age that sensed that most of its moral and other evaluative expressions were losing authority. To understand that the passions were conceived and regarded with meaning clearer, more elaborate and more systematic than they now retain, he concludes, is crucial to an appreciation of the literature of the age.