March 6, 2013

Iliad date is confirmed, thanks to science


The ‘Iliad’ codex, circa either the late 5th or early 6th century A.D.

How do you date a text from roughly 8 B.C.E.?

You track it like a geneticist. “Languages behave just extraordinarily like genes,” says Mark Pagel, an evolutionary theorist at the University of Reading in England, in a story  by Joel N. Shurkin for Scientific American about tracking Homer‘s The Iliad.

“It is directly analogous. We tried to document the regularities in linguistic evolution and study Homer’s vocabulary as a way of seeing if language evolves the way we think it does. If so, then we should be able to find a date for Homer.”

Though Homer is unlikely to be the single author of The Iliad, the story was built in one particular part of northwestern Turkey, according to Brian Rose, professor of classical studies and curator at the University of Pennsylvania Museum. Physical evidence of a struggle in that territory was discovered in the 19th Century. Archaeologist Heinrich Schliemann and Englishman Frank Calvert excavated evidence of a military conflict in the 12th century B.C.E., including arrows and five feet of burned debris around a buried fortress. There may or may not have been a war in Troy; nevertheless, there was an epic poem.

There’s a statistical model that estimates the rate of lexical replacement for common vocabulary items, called the Swadesh word list. The list includes common words like relationships (like father, mother, child), colors, and body parts. Most words have a half-life of 2,000 to 3,000 years. But not all of them do! The key to a split in languages is that the rate of replacement differs noticeably among the 200 words in the list, ranging from 500 to 10,000 years. Words that evolve rapidly will differ between closely related languages; words that evolve slowly will be shared between distantly related ones.

This is precisely the way that we measure the genetic history of humans, going back to see how genes evolve over time.

To examine the language of The Iliad, scientists tracked the Swadesh list for the Hittite, Homeric Greek, and modern Greek languages.

They looked at cognates, words derived from ancestral words. There is “water” in English, “wasser” in German, “vatten” in Swedish, all cognates emanating from “wator” in proto-German. However, the Old English “hund” later became “hound” but eventually was replaced by “dog,” not a cognate.

They constructed a phylogenetic tree based on the replacement rates. Comparing this tree to the vocabulary of Homer’s Iliad, the birth date of the text is 707 B.C.E. When they studied additional historical accounts, they decided that date is 762 B.C.E. (give or take 50 years).

Now you know! Thanks, science.



Kirsten Reach is an editor at Melville House.