The title of Hannah Arendt's book, Eichmann in Jerusalem: A Report on the Banality of Evil, published in 1963, provides the reader with a bit of a tip as to what she learned at the trial of Alfred Eichmann, a high-ranking Nazi and one of the organizers of the Holocaust, in Jerusalem in 1961. She found Eichmann to be neither sinister nor impressive. He was ordinary, and she drew corresponding conclusions about the nature of evil. Far from being the mastermind behind the genocide, he was just an obedient, unthinking, and dutiful bureaucrat. What made him evil was, in fact, his thoughtlessness. Abandoning his thinking made him dutiful in carrying out unquestioningly the orders of his superiors. Had he been a thinking person, a critical thinker, he would not have accepted the evil. Evil, for Arendt, came to be thought of as a passive enterprise and, therefore, the struggle with evil, for Arendt, requires individual vigilance, energy, and effort. This basic idea can be elaborated and supported with specific evidence either from her original reports on the trial, published in The New Yorker, or from the above-mentioned book from 1963. Arendt's conclusions were immediately critiqued and disputed by many of her contemporaries. For that reason, it may make sense to make reference to what she believed she learned from the trial.