system
Given the following post, respond as if you're commenting on Reddit:
human
[Halo] Did the covenant know about the flood before the events of Halo: ce?

In the opening of Halo 2, when the soon-to-be arbiter is on trial, the hierarchs confidently say that it wasn’t a mistake to prioritize destroying the flood over the humans, and don’t seem very surprised or unsettled by the revelation that their holy rings were infested with such an evil creature. Did they already know about the flood? Had they encountered them in other forerunner ruins at some point? We’re the flood included in their legends of the great journey?
gpt
They knew about the flood from bits and pieces of the forerunner history they had uncovered. Not enough to understand how grave the threat was but enough to know that the flood was the proverbial demons to the forerunner gods. They didn't have much concrete evidence of them existing but were aware of them much like how we know the word for bear is lost to history since our ancestors were even afraid of saying it.