Editor's Note: David Peterson is the creator of the Dothraki language used in the HBO show 'Game of Thrones.' Peterson also is a member of the Language Creation Society.  A 30-minute profile of Peterson will air on CNN's "The Next List on Sunday at 2 p.m. ET. The work of a language creator is often regarded with skepticism. … Continue reading 'Game of Thrones' linguist: How to create a language from scratch