In Chapter 31 of Watership Down, El-ahrairah tries to bring the "white blindness" to King Darzin, only to be told by the Black Rabbit it wouldn't work. El-ahrairah gives up, but then receives a boon:
Then at last El-ahrairah felt that his strength and courage were gone. He fell to the round. He tried to move, but his back legs dragged along the rock and he could not get up. He scuffled and then lay still in the silence.
"El-ahrairah," said the Black Rabbit at last, "this is a cold warren: a bad place for the living and no place at all for warm hearts and brave spirits. You are a nuisance to me. Go home. I myself will save your people. Do not have the impertinence to ask me when. There is no time. They are already saved."
Why does the Black Rabbit do this?
The standard explanation given on TVTropes is that El-ahrairah essentially browbeat the Black Rabbit into it by refusing to leave, but if that were the case, couldn't the Black Rabbit have just never told El-ahrairah that his last trick wouldn't work?
And if the Black Rabbit going to save him all along, why put him through the trial? Is the implication that Frith just set the whole thing up to teach that "Wisdom is found on the desolate hillside, El-ahrairah, where none comes to feed, and the stony bank where the rabbit scratches a hole in vain"?
