Western reflection about human nature and the politics of the human condition began with the sunburst of ancient Greece 2,500 years ago, but lurched into a new phase 70 years ago with the liberation of the Nazi extermination camps. The Holocaust is the dark sun into which humanity should stare, lest troubling lessons be lost through an intellectual shrug about "the unfathomable."

Now comes an English translation of a 2011 German book that refutes a 1963 book and rebukes those who refuse to see the Holocaust as proof of the power of the most dangerous things — ideas that denigrate reason. The German philosopher Bettina Stangneth's "Eichmann Before Jerusalem: The Unexamined Life of a Mass Murderer" responds to Hannah Arendt's extraordinarily and perversely influential "Eichmann in Jerusalem: A Report on the Banality of Evil."

Although, or perhaps because, Arendt was a philosopher, in her report on Israel's trial of Adolf Eichmann, the organizer of industrialized murder, she accepted the facade Eichmann presented to those who could, and in 1962 would, hang him: He was a little "cog" in a bureaucratic machine. He said he merely "passed on" orders and "oversaw" compliance. Arendt agreed.