‘Despair, or folly?’ said Gandalf. ‘It is not despair, for despair is only for those who see the end beyond all doubt. We do not. It is wisdom to recognize necessity, when all other courses have been weighed, though as folly it may appear to those who cling to false hope. Well, let folly be our cloak, a veil before the eyes of the Enemy! For he is very wise, and weighs all things to a nicety in the scales of his malice. But the only measure he knows is desire, desire for power; and so he judges all hearts.’
There were rockets like a flight of scintillating birds singing with sweet voices. There were green trees with trunks of dark smoke: there leaves opened like a whole spring unfolding in a moment, and their shining branches dropped glowing flowers down upon the astonished hobbits, disappearing with a sweet scent just before they touched their upturned faces. There were fountains of butterflies that flew glittering into the trees; there were pillars of coloured fires that rose and turned into eagles, or sailing ships, or a phalanx of flying swans; there was a red thunderstorm and a shower of yellow rain; there was a forest of silver spears that sprang suddenly into the air with a yell like an embattled army, and came down again into the Water with a hiss like a hundred hot snakes.
-Tolkien, The Fellowship of the Ring