Vladimir Nabokov writes in Lectures on Russian Literature:

Steady Pushkin, matter-of-fact Tolstoy, restrained Chekhov have all had their moments of irrational insight which simultaneously blurred the sentence and disclosed the secret meaning worth the sudden focal shift. But with Gogol this shifting is the very basis of his art, so that whenever he tried to write in the round hand of literary tradition and to treat rational ideas in a logical way, he lost all trace of talent. When, as in his immortal The Overcoat, he really let himself go and pottered happily on the brink of his private abyss, he became the greatest artist that Russia has yet produced.