Odin’s quest for wisdom is never-ending, and he is willing to pay any price, it seems, for the understanding of life’s mysteries that he craves more than anything else. On one occasion, he hanged himself, wounded himself with his spear, and fasted from food and drink for nine days and nights in order to discover the runes.

On another occasion, he ventured to Mimir’s Well – which is surely none other than the Well of Urd – amongst the roots of the world-tree Yggdrasil. There dwelt Mimir, a shadowy being whose knowledge of all things was practically unparalleled among the inhabitants of the cosmos. He achieved this status largely by taking his water from the well, whose waters impart this cosmic knowledge.

When Odin arrived, he asked Mimir for a drink from the water. The well’s guardian, knowing the value of such a draught, refused unless the seeker offered an eye in return. Odin – whether straightaway or after anguished deliberation, we can only wonder – gouged out one of his eyes and dropped it into the well. Having made the necessary sacrifice, Mimir dipped his horn into the well and offered the now-one-eyed god a drink.