 In part because it rests upon the idea of middle knowledge, which is itself controversial, Craig’s idea of transworld damnation may be the most controversial idea that any proponent of a free will theodicy of hell has put forward. It also raises the question of why a morally perfect God would create someone (or instantiate the individual essence of someone) whom God already knew in advance would be irredeemable. By way of an answer, Craig insists on the possibility that some persons would submit to God freely only in a world in which others should damn themselves forever; it is even possible, he insists, that God must permit a large number of people to damn themselves in order to fill heaven with a larger number of redeemed. Craig himself has put it this way: