Thus Spake Timothy Doner

"It's a bit counterintuitive, but actually, by studying multiple languages ~ from different families or from the same family ~ you begin to get a better sense of the differences between your own language and that foreign language and also, just in general, very good strategies in language-learning." So says 17-year-old Timothy Doner. And by "multiple languages," he means about 20, which is how many he speaks (story, video): http://www.economist.com/blogs/johnson/2013/07/teenage-hyperpolyglot-0