The paper reviews the philosophy and aesthetics of an outstanding Soviet thinker, the founder of the concept of left Marxist conservatism Mikhail Aleksandrovich Lifshitz (1905–1983). It describes Lifshitz’s life and work, paying attention to his “respectful friendship” with the Orthodox conservative philosopher A. F. Losev, member of the Onomatodoxy (Imiaslavie) movement. Discussions of the 1930s between Lifshitz and his movement (Lukács, Grib, Usievich, Platonov), on the one side, and Marxist “sociologizers” and “vulgar democrats”, on the other side, are described. During these discussions, Lifshitz and his associates criticized the complete reduction of art, philosophy, and morality to economic facts (the notorious Marxist base), defending the autonomy of spiritual and cultural creativity. They criticized “revolutionary, left-wing avant-garde art” and rehabilitated representatives of classical art of the past, “Great conservatives of humanity”, i.e. Plato, Aristophanes, Goethe, Pushkin, Tolstoy, and classical realistic art itself. According to Lifshitz, the latter also included old Russian art, i.e. icons. The paper shows the conservative potential of Lifshitz’s teaching on the dialectic of progress and regress that justifi es the conservative criticism of capitalism by the great realist artists of the past. It also describes Lifshitz’s criticism of the relativistic trend in Marxism and his attempt to reveal and develop the link between Marxism and classical dialectical philosophy from Plato to Hegel. The author shows that, defending the unity of the Truth, Beauty and Goodness, Lifshitz approached some kind of non-religious (possibly crypto-religious) philosophy of all-encompassing unity or unitotality. Finally, the paper off ers a look at Lifshitz’s left conservatism from the standpoint of ordinary (classical) religious conservatism, stating that his understanding of classical epochs lacked the religious component that has always been present in these epochs.