Book excerpt: Celebrated connoisseur, drawings collector, print dealer, book publisher and authority on the art of antiquity, Pierre-Jean Mariette (1694-1774) was a pivotal figure in the eighteenth-century European art world. Focusing on the trajectory of Mariette?s career, this book examines the material practices and social networks through which connoisseurs forged the idea of art as an object of empirical and historical analysis. Drawing on significant unpublished archival material as well as on histories of science, publishing, collecting and display, this book shows how Mariette and his colleagues? practices of classification and interpretation of the graphic arts gave rise to new conceptions of artistic authorship and to a history of art that transcended the biographies of individual artists. To follow Mariette?s career through the eighteenth century is to see that art was consolidated as a specialized category of intellectual inquiry-and that style emerged as its structuring analytic device-in the overlapping spaces of the collector?s cabinet, the connoisseur?s portfolio and the dealer?s shop.