In 1986 his book ("The Drowned and the Saved"), was published. In it he tried to analyse why people behaved the way they did at Auschwitz, and why some survived whilst others perished. In his typical style, he makes no judgments but presents the evidence and asks the questions. For example, one essay examines what he calls "The grey zone", those Jews who did the Germans' dirty work for them and kept the rest of the prisoners in line. He questioned, what made a concert violinist behave as a callous taskmaster?