A language is considered extinct when the last person who learned it as his or her primary tongue dies. Last month, the United Nations Educational, Scientific and Cultural Organization (UNESCO) launched an online atlas of endangered languages, labeling more than 2,400 at risk of extinction.
Michael Blake, an associate professor of philosophy and public policy at the University of Washington, said languages have always changed and disappeared over time, and he argues against the idea that all languages should be preserved.
"When we have indigenous languages in danger because of what we've done to these communities, that's the real reason" behind preservation pushes, he said. "But it's a much more complicated argument. It doesn't mean every language now has the right to be immortal."
Preservation proponents say there are cultural and pragmatic reasons to save dying languages. Many indigenous communities have in their native tongues vast repositories of knowledge about medicinal herbs, information that could provide clues to modern cures. The Kallawaya people in South America have passed on a secret language from father to son for more than 400 years, including the names and uses of medicinal plants. It is now spoken by fewer than 100 people. Preserving languages is also key to the field of linguistics, which could offer a window into the workings of the brain.