In this paper, I show that Nietzsche is a Kantian, and what being Kantian means. He accepts the idea that our perception is configured by concepts which unify and inform the world around us, and which result from a biological evolution of the human species. His Kantianism is thus biological and mainly influenced by Friedrich Albert Lange’s reading of Kant. But this Nietzschean conceptualism must be inscribed in his thought of the will to power, where the perceptive fixation of the (...) world is the result of a degeneration caused by the biological, psychological and historical recovery of the will to power. Thus, I show that Nietzsche’s Kantianism is as biological as it is axiological. (shrink)