Poncelet was taught most influentially by Monge and Carnot, and also by Ampère and Hachette. Morin, a friend, was also a collaborator. Gergonne published several of Poncelet’s papers in his journal, though the two, having arrived independently at some of the same important findings in projective geometry, engaged in a two-year dispute over priority. Arago finally persuaded him to take up a Paris professorship. Cauchy, deeply conservative, did his best to attack Poncelet’s work, effectively forcing him to publish significant work in Germany, in the journal published by Crelle, whom Poncelet greatly admired.