Here's a linguistic can of worms for you: a U.S. intelligence agency is training computers to analyze metaphors used in foreigners' conversations to determine if they are a threat to national security.

The Intelligence Advanced Research Projects Activity (IARPA), a spy version of DARPA under the director of National Intelligence, is working on something called The Metaphor Program. It's no 1960s quiz show.

The program is meant to "exploit the fact that metaphors are pervasive in everyday talk and reveal the underlying beliefs and worldviews of members of a culture."

Researchers will apparently identify and define metaphors from English, Farsi, Spanish, and Russian texts and compile them into a database. But computers will do most of the work.

The first phase of the five-year program will "develop automated tools and techniques for recognizing, defining, and categorizing linguistic metaphors." Analysts would later compare subjects' statements to the database to try to determine their intentions. There's more info in a presentation here (PDF).

Project manager Heather McCallum-Bayliss has suggested that words used by Israelis and Palestinians or China and Taiwan to describe world events could be analyzed as an example. Statements by extremist leaders could also be studied for the effect of metaphors on followers.

One of the goals of the Metaphor Program is to deliver "a functional prototype that demonstrates the automated handling of data, discovery, and semantic definition of metaphors."

It's very difficult for natural language processing software to comprehend figurative language, so that will be one tough row to hoe.

(Via The Telegraph)