He defined his best-known concept by claiming that nothing can be called good without qualification "except a good will" in his Foundations of the Metaphysics of Morals.  
Vaihinger discussed the relation between Swedenborg and this man's concept of two worlds, in a commentary on this man's Dreams of a Spirit Seer. He proposed the creation of a league to mediate international disputes in his essay "Perpetual Peace," and defined ratiocination as the judgment of a predicate with its subject in "The False Subtlety of the Four Syllogistic Figures." He defined his best-known concept by claiming that nothing can be called good without qualification "except a good will" in his Foundations of the Metaphysics of Morals.  For 10 points, name this author of The Critique of Judgment and Critique of Pure Reason who created the "categorical imperative."
Vaihinger discussed the relation between Swedenborg and this man's concept of two worlds, in a commentary on this man's Dreams of a Spirit Seer.
Immanuel Kant