 This was not something that von Neumann had much knowledge of, so it was arranged for him to take a two-year, non-degree course in chemistry at the University of Berlin, after which he sat for the entrance exam to the prestigious ETH Zurich, which he passed in September 1923.At the same time, von Neumann also entered Pázmány Péter University in Budapest, as a Ph.D. candidate in mathematics.For his thesis, he chose to produce an axiomatization of Cantor's set theory.