More than 50 years ago, philosopher Hannah Arendt reported for the New Yorker magazine on the trial of Adolph Eichmann, overseer of deportations to the extermination camps of the Holocaust. Her five-part essay eventually became the book Eichmann in Jerusalem, which should be annual re-reading, alongside George Orwell's Politics and the English Language, for all who would safeguard the moral coherence of the societies in which we live.

Most people know Eichmann in Jerusalem as the work for which Arendt coined the phrase "the banality of evil" in the book's subtitle and final words. The phrase is generally taken to refer to the total absence of correspondence between the monstrosity of Eichmann's crimes and his comportment, throughout his 1962 trial and indeed throughout his life, as the epitome of bureaucratic blandness.

It's true that Arendt dismisses him as a "clown" for his incapacity to speak or think beyond the stock phrases that reduced the worst mass murder in human history to problems of logistics, planning and accounting. But his evil, in her eyes, went far deeper than amoral sang-froid at the spilling of millions of gallons of human blood.

Eichmann's evil comprised his horrific specific acts, of course, but its fullness was found for Arendt in the complete absence of any ability to even think outside, much less against, what the zeitgeist—the spirit of the age—deemed permissible and made possible. The result led him to moral terrain much blacker than merely following orders. It led him to believe he could, like Pontius Pilate, wash his hands and absolve himself of the need to even contemplate whether right and wrong existed in a given situation.

Eichmann did not make the trains run on time for Hitler's Final Solution as a man obliged to meet the approval of those above him. He did it as a man who vested his very conscience in what others around him approved by virtue of it being something they could approve. He did not follow, or even abdicate. He was a willing—even gleeful—evacuee from his own moral faculty.

In postscripts published after other aspects of Eichmann in Jerusalem caused a firestorm of criticism for Arendt, she insisted she was not writing theoretically about something world historical but strictly factual about Eichmann as an individual in a Jerusalem courtroom facing condemnation and death. Thankfully, for the book's continued relevance and so for us, her protest is one the text itself shows as protesting too much.

"It is in the very nature of things human that every act that has once made its appearance and has been recorded in the history of mankind stays with mankind as a potentiality long after its actuality has become a thing of the past," she writes at one point.

The immediate horror she refers to was obviously the attempted immolation of the Jews but, by extension, it was also the antecedent spread of the pre-war German euthanasia program through which "mercy" was extended to the mentally disabled and, ultimately, all "useless mouths" whose proprietors could be extinguished medically. While Arendt's first focus is necessarily Eichmann, she meticulously explores how the the euthanasia program was ground zero of the ideological epidemiology of the extermination of the Jews and the annihilation of individual conscience.

For, despite her strategic protest, Arendt was not merely excavating the evil embedded in Adolph Eichmann's banality. She was writing, from the recent past for the then-present aiming toward the future we are now living, how the corruption of conscience becomes the putrefaction of moral capacity. It is a process that we who are living Arendt's future urgently need to re-examine.

For as Professor Douglas Farrow writes in this issue of Convivium: "One can no longer appeal to the fundamental demands of morality, for the state does not know what to do with moral questions. It knows only choices, choices that rest on the freedom of indifference. The choice for suicide stands on level ground with the choice against suicide… Such choices are not morally or even logically differentiable. They have no external ground at all. They are just different expressions of one and the same autonomy-and-dignity, or right to self-determination."

Even those who will not yet accept that as the origin of evil cannot escape acknowledging its parallel with a historically verifiable example of the eradication of conscience.

In Eichmann in Jerusalem, Arendt makes clear she is not merely trading in the banality of there being a little bit of the infamous S.S. Lieutenant Colonel in all of us. Reading and re-reading Arendt reminds us the question is not whether we could become Nazis. The reality is that the Nazis, in the very human banality of their evil, could be us.