"Mm." Letwin taps the table a couple times in thought. "'What are the Great Powers' is a slippery question, because while in our language we have a word for them, we've yet to find something in another language that means exactly the same thing. We often call them gods and angels when we're talking to foreigners, but that's not entirely correct. They're more like extremely powerful spirits; I've heard of God and his angels from our Sanquis Catholic immigrants, and our 'gods' are not that." He puts air quotes around 'gods.' "They and their adversaries are originally from a realm 'above' our own, called the Aether, and they came here long ago to help us and prey on us respectively." He quickly stands up, spins around and takes a small replica of the mural down off the meeting room wall. He lays it on the table and points at Zerachiel. "This is the one you mean?"