 His instructors included the historians Vasily Klyuchevsky and Robert Vipper.The young scholar declined to continue his career in the university after the 1910 Kasso affair and moved to Saint Petersburg University, where he taught for the next seven years, during which he was awarded the Master's degree for his dissertation on the effects of Freemasonry on the Russian Enlightenment.Politically close to the kadet party (of which his father was one of the leaders), Vernadsky began his career as a supporter of liberal ideas, authoring the biographies of Nikolai Novikov and Pavel Milyukov.