“The reality is that the Nazis are men like us; the nightmare is that they have shown, they have demonstrated beyond any doubt, what man is capable of” (Arendt 1945 quote from Kohn 1994). The purpose of this essay is to address the theory of “radical evil” and to establish how it originated and was incorporated into Hannah Arendt's thesis on the “Banality of Evil”. This will be done by first addressing the main concept of evil defined as “radical” by Immanuel Kant and concluding what he meant by this. Hannah Arendt's Eichmann in Jerusalem: A Report on the Banality of Evil (1963) will then be analyzed to explore how Kant's main propositions influenced and to some extent were transformed by Arendt to explain the horrors of the Holocaust. We conclude by examining how to address the nature of evil after the Holocaust. Immanuel Kant was a German philosopher active in the late 17th century and was considered “The greatest member of the idealist school of German philosophy” (Aquila 1989). . Kant's work regarding evil, particularly that covered in his work Religion, has received more attention since the beginning of the twenty-first century than in his own time (Hanson 2012). This increase in attention could be explained by a broader search for answers regarding “evil”. Previously unimaginable events that have occurred in modern times, from the Holocaust to the atrocities of 9/11, make us question morality and ourselves as a human race, leading us to questions such as “are the people responsible for these crimes normal?” “Are these people born evil?” To answer this last question from Kant's point of view, yes, these people are born evil, or at least they are born with an intrinsic capacity to become “evil”. To answer the first question, yes...... half of the paper......964) “Everything you need to know about Adolph Eichmann” FLOWERS FOR HITLER. London: Jonathan Cape Ltd Coeckelbergh, M (2003) “Can we choose evil? A discussion on the problem of radical evil as a modern and ancient problem of freedom” The metaphysics of autonomy: the reconciliation between ancient and modern. [Date accessed 12/11/13] http://doc.utwente.nl/76157/1/Can_We_Choose_Evil_in_Keen_and_Keen.pdfFormosa, P (2007) Kant on the radical evil of human nature. The Philosophical Forum, Inc [Date accessed 1/11/13] http://www.academia.edu/175810/Kant_on_the_Radical_Evil_of_Human_NatureGiddens, A (1990) The consequence of modernity. Cambridge: Polity PressHanson, E. M (2012) “Immanuel Kant: Radical Evil” Internet Encyclopedia of Philosophy. [Date accessed 9/11/13] http://www.iep.utm.edu/rad-evil/Rees, L (2006) The Nazis: A Warning From History. London: BBC Books