Kant; Practical reason; Moral law; Evil; Diabolical will.

The discussion of evil in Kantian philosophy can be seen in relation to human actions, in how good and evil are placed as schemes derived from the moral law, that is, when actions are established as good or bad; and concerning the individual who acts, that is, in the analysis of the nature of the individual, in his character. Kant's main works that discuss the topic in the first way are Groundwork of the Metaphysics of Morals and Critique of Practical Reason. And the work that discusses the theme in the second form is Religion within the boundaries of mere reason. As for evil from the individual, or what would be evil in the individual's nature, when faced with the moral law in its pure reason, the human being has a disposition towards good and a propensity towards evil. Kant maintains that this propensity is distinguished by fragility, impurity and malignancy, but not by a diabolical will that sets reason free from the command of the moral law. The present work seeks to verify whether there would be a case in which such a diabolical will could be established, despite the philosopher's dismissal of such a condition in human beings. Based on Kant's works on moral philosophy, as well as his Anthropology from a Pragmatic Point of View and his pre-critical writing Essay on Diseases of the Head, as well as Kantian commentators in the same field, we seek to go beyond the proposition Kantian approach to evil, and support the thesis that a case for diabolical will can be configured in the pathological (sick) affectation of the psyche accommodated in the condition of psychopathy. Namely: even though we possess practical reason that has good and evil as its object, the unhealthy affectation of the mind excludes pure practical reason that places the moral law as an incentive. This configuration would result in the condition of a diabolical being.