Korsgaard, C.,Creating The Kingdom of Ends, Cambridge: Cambridge University Press, 1996.

Excerpt:

“For Immanuel Kant  the  death of  speculative metaphysics and the birth of the rights of man were not independent events. Together they constitute the resolution of the Enlightenment debates about the scope and power of reason. In the Critique of Pure Reason Kant shows that theoretical reason is unable to answer the questions of speculative metaphysics: whether God exists, the soul is immortal, and the will is free. But this conclusion that prepares the way for an extension in the power of practical reason. Practical reason that directs that every human being as a free and autonomous being must be regarded as unconditionally valuable. In his ethical writings hot shows how this directive provides a rational foundation for morality, politics, and a religion of moral faith. Bringing the reason to the world becomes the enterprise of morality rather than metaphysics, and the work as well as the hope of humanity.”

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