Space Journeys in the 17th Century as Thought Experiments?

International audienceThe discoveries realized with Galileo’s telescope made the idea of space journeys a commonplace in both literature and philosophy of the seventeenth century. Do these imaginary voyages provide more than metaphors of scientific knowledge? Can they be seen as a way to explore the consequences of copernican revolution? How could they relate with thought experiments? To answer this last query requires to give a definition and to attribute a function to thought experiment in natural philosophy. It also depends on the status of fiction, especially the dream, in philosophical matter and manner. In my paper I shall scrutinize several uses of space journeys, from Kepler to Fontenelle, and focus on the justifications of such literary devices by their authors