The Once and Future King Book 1, Chapter 18
Arthur waits in his bed for Archimedes to come get him and turn him into a bird. He thinks about the beautiful spring night, and the infinity of the stars in the sky, and falls asleep. Archimedes arrives and gives him a dead mouse to eat, which somehow he suddenly finds delicious. He gets his bearings in the air and takes off. Archimedes teaches him how to fly as an owl. He catches a sparrow for himself, but tells Arthur he can't do it too, because no owl kills unless he is really hungry. Archimedes, on Merlyn's instructions, then turns Arthur into a wild goose.
The world is now flat for Arthur, because it is night and the only thing he can see is mud, which is totally featureless. The only other things he can make out are the sound of the roaring ocean and the dim lights from a few fishermen's cottages. He stands amid a large crowd of geese, who begin talking excitedly as the sun comes up. They are in family groups, and Arthur feels uncomfortable joining one, but as soon as the goose next to him flies up into the air, he follows her instinctively. Later, he talks with her as they eat the grass from a field. He admits that he doesn't know the ways of geese because he is human, and she isn't too surprised-she has heard of this before. But when he asks her if they are at war with any other geese, she gets very offended. She can't believe that any species would fight against itself. She only understands defending oneself from natural predators, like foxes. For a while, she won't even talk to Arthur about it. Then she forgives him, seeing he is confused. She tells him her name is Lyo-Lyok and that the reason birds don't have war is because they can't fight over boundaries-there are no boundaries in the air. Arthur tells her he likes fighting, and she answers, "Because you're a baby." Book 1, Chapter 18, pg. 172