Hilberg came to be considered as the foremost representative of what a later generation has called the functionalist school of Holocaust historiography, of which Christopher Browning, whose own life was changed by reading Hilberg's book, is a prominent member. The debate is that Intentionalists see "the Holocaust as Hitler's determined and premeditated plan, which he implemented as the opportunity arose", while functionalists see "the Final Solution as an evolution that occurred when other plans proved untenable". Intentionalists argue that the initiative for the Holocaust came from above, while functionalists contend it came from lower ranks within the bureaucracy.