Arendt's book introduced the expression and concept of the banality of evil.[15] Her thesis is that Eichmann was actually not a fanatic or a sociopath, but instead an average and mundane person who relied on clichéd defenses rather than thinking for himself,[16] was motivated by professional promotion rather than ideology, and believed in success which he considered the chief standard of "good society".[17] Banality, in this sense, does not mean that Eichmann's actions were in any way ordinary, but that his actions were motivated by a sort of complacency which was wholly unexceptional.[18]
Many mid-20th century pundits were favorable to the concept,[19][20] which has been called "one of the most memorable phrases of 20th-century intellectual life,"[21] and it features in many contemporary debates about morality and justice,[16][22] as well as in the workings of truth and reconciliation commissions.[23] Others see the popularization of the concept as a valuable warrant against walking negligently into horror, as the evil of banality, in which failure to interrogate received wisdom results in individual and systemic weakness and decline.[24]