In 1901
Peter Berngardovich Struve invited Frank to contribute to his collection,
The Problem of Idealism (published in 1902), which criticised materialism and positivism. He spent the next five years between Moscow and Germany, writing and translating philosophical works and assisting Struve. Between 1902 and 1905, he contributed to Struve's periodical,
Osvobozhdenie ('Liberation'), published in Stuttgart (1902–1904) and Paris (1904–1905). In 1906 he moved to St Petersburg and contributed philosophical essays to Struve's periodical,
Russkaya Mysl. In 1908, he contributed to the influential symposium,
Vekhi ('signposts'). In 1908, he married Tatyana Sergeevna Bartseva (1886–1984) with whom he would have four children: Alexei (1910–1969), Natalia (1912–1999), Vasiliy (1920–1996) and Victor. In 1912, he converted to
Orthodox Christianity, and began lecturing on philosophy at St Petersburg University. Later, he wrote, "I consider my Christianity as the completion of my Old Testament upbringing, as an organic evolution based on the religious foundations which I accepted in my childhood". Frank spent 1913–1914 in Germany, where he wrote
Der Gegenstand des Wissens ('The Object of Knowledge') for which he received his master's degree (1916). It was followed by his
Dusha Cheloveka ('Man's Soul') (1917). In summer 1917, Frank was appointed dean of the arts faculty of the new University of Saratov. In 1921, he was appointed to the chair of philosophy in Moscow University. There he joined the philosopher
Nikolai Berdyaev, who was directing the Free Academy of Spiritual Culture. On 29 September 1922 some 160 prominent intellectuals and their families were expelled (at their own expense and not return without the permission of the Soviet authorities) on a so-called "
philosophers' ship" from
Petrograd to
Stettin, where they arrived on 2 October. Frank spent the rest of life supported by the
World Council of Churches and his friend
Ludwig Binswanger who was one of the most famous psychiatrists in the world. Since the 1930s, cooperation with ecumenical journals and organizations became increasingly important for Frank. In December 1931 he was elected as head of the Russian Scientific Institute (RSI) in Berlin. On 7 April 1933, the
Law for the Restoration of the Professional Civil Service required an
Aryan certificate from all employees and officials in the public sector, including education. His Jewish ancestry rendered him unemployable in Germany. For a couple of months he was succeeded by
Ivan Ilyin and then by Adolf Ehrt. In January 1936 Frank stopped collaborating with the Kantian Society. Fleeing the Nazi persecution, he moved to Paris in 1937. During his exile, he published several books and articles in Russian and articles in German, French and one in Dutch "De Russische Wereldbeschouwing" (1932). According to
Willem Adolph Visser 't Hooft he was a great authority on religion and metaphysics. He and his wife survived
World War II by hiding near
Grenoble; thanks to the intercession of
J.R.R. Tolkien, the Russian philosopher received a scholarship from the World Council of Churches. Their four children escaped to Britain. In the early years of the war he wrote 'God With Us', the first of his works to be translated into English (published in 1946). In 1945, he and his wife moved to Britain. Frank died of
lung cancer (?) in London. He and his wife are buried in
Hendon Cemetery in London. ==Metaphysical libertarianism==