  After a brief tenure in Leipzig, Vaihinger moved to Berlin, where he continued his studies with Hermann von Helmholtz and the Neo-Kantian Eduard Zeller. In 1876, Vaihinger published his first work, an exposition and defense of Lange’s brand of Neo-Kantianism, entitled Hartmann, Dühring, and Lange: Towards a History of German Philosophy in the Nineteenth Century. It was here that the views which would form the basis of the PAO first began to take shape. In autumn of the same year, Vaihinger again relocated—this time to the University of Strassburg—and by early 1877 he had habilitated with a work entitled Logical Studies on Fictions. Part I: The Theory of Scientific Fictions. Though the PAO would not be published for more than 30 years, the Logical Studies is already, according to Vaihinger, “exactly the same” as Part I of the former work (PAO xxiii–xxiv).