Powers Unknown

The deal with the blog is that a single word or phrase in a work by Poul Anderson can generate either a reflection or a comparison with a similar word or phrase in a work by another author. We can move in any direction although we always return to our source. And here is one mysterious phrase:

"The Taverners are as merciful as their charter, or whatever it is that was once granted them by some power unknown, allows them to be."
-Poul Anderson, "Losers' Night" IN Anderson, All One Universe (New York, 1997), pp. 105-123 AT p. 108.

There could be a story about an inn-keeping couple at some place and time, the punchline being that, right at the end of the story, they are appointed as keepers of the Old Phoenix - but that alone would not be enough to tell us who the power unknown is. Once appointed, do the Taverners remain in the Old Phoenix or do they, like their guests, continue to lead lives in one of the universes? The inn is outside all particular cosmic times so they could always return to it at the moment they had left.

"...there are some powers that no one, not even the Endless, seeks to inquire into too deeply."
-Neil Gaiman, The Sandman: The Wake (New York, 1997), p. 17, panel 4.

Why not? The Endless are anthropomorphic personifications of aspects of consciousness and include Destiny, who knows all that was, is and will be, although Delirium that was Delight claims:

"...I know lots of things about us. Things not even he knows."
-Neil Gaiman, The Sandman: Season Of Mists (New York, 1992), p. 29, panel 6.

- pointing at Destiny.

That might be a koan: What does Delirium know that Destiny does not?

And does she know the powers unknown?