How did Schopenhauer deal with the concept of a priori knowledge in his Fourfold Root of Reason?
Schopenhauer takes as his centre-piece Immanuel Kant’s concept of a priori knowledge, that is, knowledge that is innate to the mind, thereby being independent of experience. He tries to produce an explanation of the objective world, bringing in the concepts of free will and causality. Hence he is more of an objective Idealist. Schopenhauer formulated his views in his book The World as Will and Representation.
