The claim made in this new book is that Eichmann was far more intelligent than he let on, and that he essentially fooled everyone by telling them what they wanted to hear. Evidence is provided in the form of his writings about the moral philosophy of Kant, and previously-mislabeled transcripts from postwar interviews conducted in Argentina by a fellow member of a sort of Nazi book club they were running. Basically all this evidence was out there, it was just misclassified or mislabeled and so no one had connected the dots.