When you bred dogs, what you got was a different kind of dog – not a banana or a fish. And breeding animals was the purest kind of magic: if a human being wanted a long thin dog, and if they started from short fat ones, and if they knew how the trick worked (if, so to speak, they cast the right ‘spells’) then they would get a long thin dog. Bananas, long and thin though they might be, were not a good starting point.
