“One felt as if there was an enormous well behind them, filled up with ages of memory and long, slow, steady thinking; but their surface was sparkling with the present.”

This is J. R. R. Tolkien describing the eyes of Treebeard in the second part of his trilogy, The Lord of the Rings. Treebeard is an Ent, a shepherd of the forest. In a letter to the poet W. H. Auden, Tolkien wrote of the walking-talking Ents (manlike trees, 14 feet tall, with rootlike toes), “I did not consciously invent them at all.” While he admits that as a schoolboy he was annoyed by Shakespeare’s Great Birnam wood—“I longed to devise a setting in which the trees might really march to war”—he says he felt he was “reporting” the Ents, not inventing them. (And yet, Ent is the last three letters of invent.)