"The obvious," she said, turning back to face the writing. Her horn shone again, the better to cast the letters into relief. "That we are being manipulated as pawns in some grand game, and that setting us on this quest serves some greater purpose to whatever power brought us here. That so little is explicitly spelled out that the truth of the matter could be anything, and yet that some truth is likely to be in the words, since it is so deliberately being obscured."

The lesson here was that Celestia put a great deal of thought into things -- since that, after all, was just what she considered obvious.