It is impossible to achieve greatness in one's own time. Greatness makes itself known only to descendents, for whom such a quality is always located in the past (it turns into a distanced image); it has become an object of memory and not a living object that one can see and touch. In the genre of "memorial," the poet constructs his image in the future and distant plane of his descendents (cf. the inscriptions of oriental despots and of Augustus). In the world of memory, a phenomenon exists in its own peculiar context, with its own special rules, subject to conditions quite different from those we meet in the world we see with our own eyes, the world of practice and familiar contact.
M. M. Bakhtin, The Dialogic Imagination: Four Essays, Caryl Emerson & Michael Holquist (trads.), University of Texas Press, 1987.