From "Eichmann, the Banality of Evil, and Thinking in Arendt's Thought" by Bethnia Assy
Eichmann in Jerusalem (2) was originated when Hannah Arendt went to Jerusalem in order to report, for The New Yorker, on the trial of Otto Adolf Eichmann, (3) who was acused of crimes against the Jewish people, crimes against humanity, and war crimes. The trial began in April 15, 1961. The New York Times had announced Eichmann's capture by Israeli agents in Argentina, in May 24, 1960. Israel and Argentina had discussed Eichmann's extradition to Israel, and the United Nations finally decided the legality of Jerusalem Trial. After the confirmation that Eichamnn was to be judged in Israel, Arendt asked The New Yorker's director, William Shamn, to do a complete report of the Eichmann case in Israel.
Arendt's first reaction to Eichmann, "the man in the glass booth," was — nicht einmal unheimlich — not even sinister." (4) She argues that "The deeds were monstrous, but the doer … was quite ordinary, commonplace, and neither demonic nor monstrous." (5) Arendt's perception that Eichmann seemed to be a common man, evidenced in his transparent superficiality and mediocrity left her astonished in measuring the unaccounted evil committed by him, that is, organizing the deportation of millions of Jews to the concentration camps. Actually, what Arendt had detected in Eichmann was not even stupidity, in her words, he portrayed something entirely negative, it was thoughtlessness. Eichmann's ordinariness implied in an incapacity for independent critical thought: "… the only specific characteristic one could detect in his past as well as in his behavior during the trial and the preceding police examination was something entirely negative: it was not stupidity but a curious, quite authentic inability to think." (6) (emphasis added) Eichmann became the protagonist of a kind of experience apparently so quotidian, the absence of the critical thought. Arendt says: "When confronted with situations for which such routine procedures did not exist, he [Eichmann] was helpless, and his cliché-ridden language produced on the stand, as it had evidently done in his official life, a kind of macabre comedy. Clichés, stock phrases, adherence to conventional, standardized codes of expression and conduct have the socially recognized function of protecting us against reality, that is, against the claim on our thinking attention that all events and facts make by virtue of their existence." (7)
The full article, if you are interested, is here .