Concluding Unscientific Postscript to the Philosophical Fragments is a major work by Søren Kierkegaard. The work is an attack against Hegelianism, the philosophy of Hegel, and particularly Hegel's Science of Logic. The work is also famous for its dictum, "subjectivity is truth". It was an attack on what Kierkegaard saw as Hegel's deterministic philosophy. Against Hegel's system, Kierkegaard is often interpreted as taking the side of metaphysical libertarianism or free will, though it has been argued that an incompatibilist conception of free will is not essential to Kierkegaard's formulation of existentialism.
Concluding Unscientific Postscript to the Philosophical Fragments is a sequel to the earlier Philosophical Fragments. Despite the title of the work, Postscript is almost five times larger than the original work. The pseudonym "Johannes Climacus" is credited as the author and Kierkegaard as an editor. Like his other pseudonymous works, Postscript is not a reflection of Kierkegaard's own beliefs. However, unlike his other pseudonymous works, Kierkegaard attaches his name to this work by crediting himself as an editor.