The article discusses the aesthetic concepts of Konstantin Leontiev (1831-1891), I. Kant and F. Nietzsche. The author explores the interrelation and differences of the ideas of Kant, Nietzsche and Leontiev on aesthetics, and also substantiates the similarity of the aesthetic concepts of Leontiev and Nietzsche, which allowed the Russian thinker to be considered a harbinger of Nietzscheanism. It is revealed in the article that aesthetics is the main criterion for Konstantin Leontiev on the basis of which the thinker appraises all phenomena occurring in life and nature (the so-called "aesthetics of life"), and also explores the essence of the world and the laws of its development. The author substantiates that aestheticism had a significant impact on the formation of Leontiev's socio-political views. Despite the fact that Leontiev went from a period of short-term fascination with liberal ideas to the stage of radical conservatism, aestheticism has always remained the unchanging foundation on which the thinker created his socio-political concepts. At the same time, Leontiev's aestheticism was not an ideology, but an integral worldview of the thinker, which conditioned his acceptance of conservative views. The research analyzes the works of Konstantin Leontiev, I. Kant and F.Nietzsche, as well as the works of Russian scientists devoted to the socio-political views of Leontiev.
