The Paradox of Imperfect Duty in Kant's Moral Philosophy. A Problem in 'Applying' Ethics'

The Applied Ethics debate has not yet sufficiently clarified what application of ethics exactly is. The issue of application is considered to be especially problematic in Kantian ethics or in discourse ethics. This article describes the concept of applying ethics in Kant. In discussing the duty of helping others and the theory of its application in Metaphysics of Morals it is shown that a strict separation of justification and application in ethical theory results in the paradox of imperfect duty. The paradox says that the duty to help others would be fulfilled without ever being fulfilled in action. To overcome the paradox it is necessary to form submaximes of helping, which are not arbitrarily but instructed by a theory of casuistry. This casuistry, if it is considered as a doctrine of application in Kantian ethics, can overcome the paradox of imperfect duty. However, the casuistry can overcome this paradox only if it is understood as a philosophy of prudence, which can be found in Aristotle or Descartes.