This chapter explores the early forms of intellectual exchange among 17th-century mathematicians, focusing on Marin Mersenne's extensive correspondence network and his role in disseminating mathematical puzzles and challenges across Europe. Mersenne's letters formed a virtual academy, connecting scholars and circulating ideas.
How scholars around Europe created an international network of intellectual exchange. As examples we consider the activities of Mersenne, Peiresc, Leibniz, Calvet, and Hartlib.