- last post: 01.01.0001 12:00 AM PDT
It's been controversial. Some think he means the Forerunner, some say he was referring to the Flood.
It would make more sense that he was referring to the Forerunner. As without the Halos, the Flood would spread and bring about ruin and destruction.
He could also be glad that the Flood survived to produce ample specimens under containment for research(research..by whom, is the question-supposedly the Forerunner died off). If he is referring to the Flood, then there's no doubt of another hidden purpose of Halo that the Flood have to be dependent on it to survive. From the Conversations of the Universe, it is implied by Prophet of Supposition whether the Flood had sanctuary on the Halo.