Casanova met Mozart in Prague, attending the première of his opera Don Giovanni (there’s a story that he amended da Ponte’s libretto so as to reflect his own experiences). He claimed to have sat next to Franklin and listened to him discussing aeronautical balloons. He described Haller, whom he stayed with, as a physical as well as mental colossus. He visited Rousseau on the pretext of asking him to copy out some music, and amused himself on the way back by describing his eccentric habits. He told Voltaire that he thought him “the greatest genius our continent has produced.”