In the Groundwork of the Metaphysics of Morals, the author analytically explicates the following from the common, confused concepts of morality: that it is absolutely necessary to arrive at one ultimate practical principle that can be known a priori, and thus make reason alone the source of the human being’s moral capacity if such a being does not want to entirely renounce all morality and surrender itself to only those sensations that are part of its animal nature; that this practical law of reason concerning human moral conduct, when conceived purely, leads to the idea of metaphysical freedom, and thus discloses the human being to itself in a higher form entirely independent of the sensible world and its laws, as well as in a very particular dignity, as the member of a distinct, intelligible world.