For all practical purposes, the Odyssey is the "sequel" to the earliest well-known surviving work in Western literature, the Iliad. (The Epic of Gilgamesh, while at least 1,000 years older, is neither as well-known nor as influential as Homer's work.) Unlike many sequels in the present era, however, the Odyssey actually seems to be an improvement, in some respects, on the original, and stands quite well as an independent work.
Odysseia—the poem's name in Greek since Herodotus called it that in the fifth century BC—means simply "the story of Odysseus." The word "odyssey" that derives from this name has come to mean any significant and difficult journey. Although the poem is technically about one particular man's journey, as Horace observed in his first Satire, "mutato nomine, fabula de te narratur," "just change the name and the story could be told about you."
If we were to call the Iliad the world's first adventure story, the Odyssey could be called its first opera: certainly some of the plot twists along the way would be at home in that extravagant genre. In the context of Odysseus' s voyages and troubles, the poem touches on a number of significant topics such as loyalty, heroism, creativity, and order. Where the Iliad is noteworthy for its similes and epithets, the Odyssey is justly famous for its use of symbolism and for the pace and variety of its action.
For more than 1,500 years the Iliad and the Odyssey set the standard by which epic poetry, if not all poetry of any kind, was judged. The epic form in poetry has not been widely practiced since the appearance of John Milton's Paradise Lost in 1667, but the story of Odysseus's wanderings has remained a perennial favorite to the present day.
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