ABSTRACT
In the course of the seventeenth century the printed word became an increasingly important tool for natural philosophers. They discussed it self-consciously, used it voraciously, and clamoured to include the latest technological improvement in their books. Writing in 1600, the German astronomer Johannes Kepler (15711630) linked publication to the growing publicity of knowledge. In his history of astronomy he presented ancient astronomy as a largely private enterprise charac terized by poor communication among its participants, who often had little knowledge of each other’s activities. Nor, Kepler remarked, did that knowledge survive much beyond their lifetime since books did not yet have a central role in the transmission of ideas, ‘owing to the lack of printing, I imagine’.1 Printing, in short, was not simply a technology in the eyes of this early modern natural philosopher. It was a medium that transformed the very definition and content of knowledge itself, giving books a status in the learned world that they could not have enjoyed in a society that valued the oral transmission of ideas.
