A document discovered in the Roman archives of the Jesuits sheds new light on the involvement of the Jesuit mathematician Christoph Scheiner in the trial of Galileo. The document suggests that Scheiner did not initiate the 1632–33 proceedings against Galileo, despite a long suspicion of his role in the events leading to Galileo’s condemnation, abjuration, and house arrest. An exploration of the contrasting conceptions of the scientific enterprise competing for hegemony within the Society of Jesus at the time of the (...) trial leads to the development of a model of scientific exchange based on money rather than gift giving. (shrink)