Once upon a time there were two groups of gods. One group was called the Æsir and the other was called the Vanir. They had been quarrelling with each other for a very, very long time. At last everyone grew tired of the quarrelling. "We will stop," said the Æsir. "We will stop too," said the Vanir. And so they decided to swap helpers with each other, so that everyone could trust that the peace would hold.
The Vanir sent Njörðr, who was wise and kind and smelled of the sea, and his son Freyr, who was strong and cheerful. They were the best the Vanir had. The Æsir were pleased.
Now the Æsir needed to send someone back. They looked around. Who could they spare? And then they spotted Hœnir. Hœnir was the tallest god in all of Asgard. He had broad shoulders and a handsome face and a voice that sounded like distant thunder. He looked exactly the way an important god should look.
The only trouble was that Hœnir was not very good at thinking for himself. He could speak beautifully, yes, but only if someone whispered to him what to say. So the Æsir sent Mímir along with him, the wisest of them all. Mímir could whisper the answers to Hœnir, and Hœnir could say them in his fine voice, and everyone would be impressed.
At first everything went well. The Vanir liked Hœnir. They let him be the leader at their meetings. Mímir always sat beside him and whispered, and Hœnir said clever things, and everyone nodded.
Then one day Mímir was gone. He had wandered off for a while. The Vanir asked Hœnir: "What should we do about the fields in the east?" Hœnir stood silent for a long time. "Let the others decide," he said at last. They asked again: "Where should we build the new barn?" Hœnir looked down at his feet. "Let the others decide," he said. Whatever they asked, the answer was always the same.
The Vanir understood that Hœnir was not as clever as he looked. They felt sad and disappointed. "This was not fair," they said. They wanted a truly wise helper. So they decided that Mímir, who was the truly clever one, should be sent back to Odin. Mímir set off alone, with a long journey ahead of him.
Odin received Mímir. Mímir was tired after the long journey, though. He was old and worn, and his strength had drained from him like water from a cracked jug. Odin understood that Mímir needed a new kind of life. So Odin used his very strongest magic, the most secret runes and the oldest songs. And Mímir was transformed. He became a talking head, small and easy to carry, with eyes that still glittered with wisdom.
From that day on, Mímir was Odin's advisor. Odin carried him along and asked questions, and Mímir answered, and the answers were always wise. They were a strange and rather odd pair: the stubborn god with his one eye and the small wise head that always had an answer.
And Hœnir? He stayed with the Vanir. They were not angry with him any longer. They understood that he had done his best. He was still the tallest god among them all, and sometimes he helped with things that suited him. Carrying heavy things, for instance. You did not need to think very much for that.