The US Intelligence Advanced Research Projects Activity is building a system to understand human metaphorical speech.
Why metaphors? "Metaphors have been known since Aristotle as poetic or rhetorical devices that are unique, creative instances of language artistry (for example: The world is a stage; Time is money).
Over the last 30 years, metaphors have been shown to be pervasive in everyday language and to reveal how people in a culture define and understand the world around them," IARPA says.