the rise both in killing and in working was consistent; the rules were simply clearer than before. As long as prisoners were fit for work they were to be kept alive. As soon as they were useless they must die, so as not to waste resources on feeding and housing them. The principle did not apply to the death camps – Sobibor, Treblinka, Belzec – whose sole purpose was the killing of Jews. Yet such was the need for slave labour by 1943 that more and more of the Jews sent to Auschwitz were also being diverted from the gas chambers and put to work if deemed useful enough.
