Are Elvish, Klingon, Dothraki and Na’vi real languages? – Recommended by Mel

https://ed.ted.com/lessons/are-elvish-klingon-dothraki-and-na-vi-real-languages-john-mcwhorter

This is a really good lesson on the construction of fictional language by authors and sometimes with the help of their loyal readers. Real languages have grammar rules, exceptions to the rules, ambiguities, they change over time and geography. But when does a ‘fake’ language become a real one? Is it when people speak it? How many people need to speak it and under what conditions? I wish the author would have mentioned languages such as Esperanto, and the reconstruction of ancient languages such as Hebrew.  At least I have.