The publication is devoted to the reconstruction of the relations that established between the philosopher, sociologist, anarchist A.A. Borovoi and the young philosopher I.A. Il’in. The ideological and political position held by A.A. Borovoi as a Private Associate Professor of the Faculty of Law of the Moscow Imperial University is reconstructed, as well as his attitude to other colleagues, in particular to P.I. Novgorodtsev, B.A. Kistyakovsky. The evolution of the views of the young Ilyin, who initially sympathized with radical political trends and the anarchist movement, and then switched to the positions of liberal conservatism, is demonstrated. Based on memoirs, letters stored in the archives of A.A. Borovoi in RSALA (Russian State Archive of Literature and Art), memoirs and letters of I.A. Il’in, as well as studies dedicated to Borovoi and Ilyin, the period of meetings of thinkers in Paris in 1911–1912 is reproduced in more detail. The details of the changes that occurred at the Faculty of Law of the Moscow Imperial University in connection with the “Casso Case”, which had a different impact on the fate of thinkers, are revealed. The relationship between Borovoi and Il’in with B.A. Kistyakovsky, who was also in Europe in 1911, is mentioned. An assumption is made about the reasons for the cessation of communication between I.A. Il’in and A.A. Borovoi during the World War I, which could be associated both with the ideological differences between the philosophers and the activities to which each of them devoted himself during these years. The meeting between Borovoi and Il’yin after the February revolution could have given rise to a resumption of communication, but the difference in assessment of the October revolution (imaginary or real) became a stumbling block. Based on the fragment mentioned by Borovoi from the book by G.I. Kish “Hitler and others” and the archive of I.A. Il’in there is reproduced an episode of the thinker’s speech at a meeting of the “Men’s Club” in March 1930. The article recreates the history of relations between I.A. Il’in and representatives of the conservative wing of German entrepreneurs and the failed cooperation with the centrist party represented by German Catholics.