The authors give the examples of how the involvement of new sources makes it possible to overcome stereotypical ideas about the stages and nature of the study of the history of Russian philosophy: in particular, the idea that in the 1930s – 1950s ancient and medieval Russian philosophy, Russian religious philosophy of the XIX–XX centuries and the philosophy of Russian emigration haven't been studied. The importance of recording and publishing any accidentally preserved sources on this topic is noted. The list of questions for the exam in the history of Russian philosophy, found in the personal archive of Academician Ivan Timofeevich Frolov (1929–1999) (compiled for students by the Department of the History of Russian Philosophy of the Faculty of Philosophy of Moscow State University in 1952), is published. The authors give a general description of this list of questions and their assessment of how it reflects the state of development of the history of Russian philosophy in the first half of the 1950s. Moreover, the article describes the main events of the scientific biography of Academician I.T. Frolov, related to the subject of the history of Russian philosophy: from his first scientific paper devoted to the problems of studying the history of Russian philosophy that were topical at that time, to his last interview for “Voprosy filosofii” (Problems of Philosophy), where I.T. Frolov shared his plans for the study of Russian philosophy, history and culture.