The World Tree Picture

According to Mythology...
Like the octave, the spiral, the mandala, the fractal, the image of the tree represents a template for the structure of reality, and the emergence of multiplicity (branches, twigs and leaves) out of unitty (the trunk), of the visible (the tree above ground) out of the invisible, (the hidden part of the tree - the roots below ground).
Many ancient cultures incorporate the myth of the World Tree, or Tree of Life, Tree of Knowledge, Tree of Speech, as it is also known.
In Nordic mythology the World Tree or Yggdrasil of the Eddas is the giant ash tree that links and shelters all the worlds. Beneath the three roots the realms of Asgard, Jotunheim, and Niflheim (Gods and giants) are located, and also the Well of Wisdom and the Well of Fate, and the Hvergelmir (Roaring Kettle), the source of many rivers. In the Tongan/Fijian myth of creation there is at the beginning of things the "Tree of Speech" which, like the giant Ash Yggdrasil, this is the gathering place of the gods, and the tree grows by a fountain, the Water of Life. The three worlds are represented by three parts of the world tree - branches, trunk and roots. The branches are the home of the Gods, the middle is the earth / land of the giants, and the roots of the tree is the underworld.

According to WarCraft III...
Alexstrasza, the Life-Giver, placed a single, enchanted acorn within the heart of the Well of Eternity. The acorn, activated by the potent, magical waters, sprung to life as a colossal tree. The mighty tree's roots grew from the Well's waters and its verdant canopy seemed to scrape the roof of the sky. The immense tree would be an everlasting symbol of the Night Elves' bond with nature, and its life-giving energies would extend out to heal the rest of the world over time. The Night Elves named their World Tree, Nordrassil, which meant "crown of the heavens" in their native tongue.

See also
Trees: 'Nature's Night', 'Synergetic Parasite', 'Dark-Light Opposition', 'Feeble Fingers' and 'Feeble Fingers, Strong Hands'
Use of trees for different purposes: 'Waiting for Godot', 'Nostalgia', 'Solid Picture of Reality', 'Just Strewn Anywhere' and 'In the End'
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