What lessons does Wart learn when he is turned into different animals?
Merlyn turns Wart, the young Arthur, into many different animals so that he can learn about kingship. For instance, he turns Wart into a fish so that he can learn to be compassionate toward the roach, a needy fish, and can warned of the dangers of despotism through the tyrannous and indolent pike, who rules through cruelty.
Merlyn also turns Wart into a merlin, a kind of bird, so that Wart can experience the damaging effect the emphasis on lineage has on the other hunting birds, rendering them almost psychotic.
Later, Merlyn turns his protege into an ant. In the ant colony, Wart is considered insane because he does not work non-stop. He also learns about the tyranny of the masses and the tyranny of conformity.
Every animal Wart lives as teaches him a piece of wisdom he will need to rule the kingdom with compassion and strength. White therefore illustrates the importance of actual experience to ruling: Wart could never have learned what he did from a book. All of these experiences together allow him to pull the sword from the stone, proving him worthy to be king.
Wart learned many lessons from his experiences turning into different animals, some specific to the particular type of animal but most capable of being generalized for use in many situations.
Aside from learning how to swim as a fish when he was a perch, he gained appreciation for the different kinds of skills needed to survive as another life form. He learned that his point of view was not the only one and quite possibly not the correct interpretation. He learned to be aware of the potential for good and for danger in unsuspected places and encounters. Wart learned bravery during his ordeal as a merlin. As an ant, Wart experienced mind-numbing conformity and truly came to value being able to think and act for himself.
Through it all, Wart gains appreciation of nature, learns to be resourceful within himself and in relationship with those around him, and becomes sensitive to the world and others in it.