The nineteenth century in France is a nightmare for literary historians. Their thirst for categorization is more easily quenched by prior centuries, to which, because they seem unified by cohesive preoccupations and common goals, such appellations as the Renaissance, the Classical Age or "le grand siecle, " and the Enlightenment or Age of Ideas are appropriately applied. For the protean nineteenth century, for which no such handy tag has been or can be devised, is beyond all else distinguished by extreme heterogeneity and eclecticism. A period of chaotic social and political instability, of...