Kant gives place to the concept of evil sometimes clearly and sometimes implicitly throughout his philosophical life. It is possible to find this in his articles on Lisbon earthquake implicitly. On the other hand for instance in his article on theodicy he expresses his rejection against traditional understanding of evil before the court of reason. In his after-critique period he mostly focuses on possibility of acting according to ethical principles in interpersonal relations. In this regard he treat the relation between reason and will that is determined by the moral law that constituted by reason itself. At this point evil is identified indirectly as will’s following other incentives rather than moral law. In the advancing years including his theological and anthropological studies, Kant tries to explore the meaning of evil in itself. He grounded his thoughts in thesis of radical evil. It is, superficially, depends on three assumptions. (1) Naturally human being is inclined to evil innately. (2) Inclination to evil is universal. (3) The roots of this evil in human nature cannot be extirpated. The aim of this paper is to investigate Kant’s thesis of radical evil according to these three assumptions. Second aim is to interpret whether this thesis is consistent with his former thoughts. And last aim is to contact the relation between radical evil thesis and Arendt’s thesis of banality of evil.
good, evil, radical evil, will, reason, banality of evil