"There remains a most important point in which the Kantian system is often misunderstood. It reveals itself plainly in every case of wrong-doing. Duty is only towards oneself; Kant must have realised this in his earlier days when first he felt an impulse to lie. Except for a few indications in Nietzsche, and in Stirner, and a few others, Ibsen alone seems to have grasped the principle of the Kantian ethics (notably in "Brand" and "Peer Gynt")."

Otto Weiniger, on Ibsen