A language that can be spoken, hummed, or whistled? A language with no unique words for color or numbers? Linguistics professor Daniel Everett claims that the unique language of the Piraha people of the Amazon is exactly that. More than 30 years ago, he traveled as a missionary into the amazon rainforest to teach the tribe, but they ended up teaching him. Their way of life and unique form of communication have profoundly changed Everett, and inspired a theory that could undermine the most powerful theory (or theorist) of linguistics.