Repetition (Kierkegaard book)

Repetition: A Venture in Experimental Psychology (Danish: Gjentagelsen: Et Forsøg i den eksperimenterende Psychologi) is an 1843 book of philosophical fiction by Søren Kierkegaard that is semi-autobiographical. The book was written under the pseudonym Constantin Constantius to reflect its theme of repetition. The book's narrator explores the question of whether true repetition can exist and includes his experiments with this idea and his interactions with an unnamed melancholic character referred to only as the "Young Man".

Kierkegaard published Fear and Trembling, Three Upbuilding Discourses, and Repetition all on the same date, 16 October 1843. While Abraham was the main character in Fear and Trembling, and the Three Upbuilding Discourses were about love, Repetition presents a noticeable contrast between the other two books.