At the beginning of the Second World War, Corneille attended drawing classes at the State Academy of Fine Arts in Amsterdam, where he befriended Karel Appel. In 1947 Corneille left the conservative Dutch climate to stay in Budapest. There he came into contact with the Frenchman Jacques Doucet, who would later join the Cobra group as well. Corneille was very impressed by the freedom and rawness in his work. Famous Swiss artist Paul Klee (1906 –1940) inspired Corneille to look for the origin of creativity in the naive and unformed. This idea would also play an important role within Cobra.