For example:
oneeyedunicornhunter (at Thu May 08, 2008 12:48 pm JST) wrote:dune takes place God-knows-how-many years in the future. they probably wouldn't even speak english! when Ghani and Leto talk in ancient languages for private conversations, they might be speaking english...or perhaps spanish...or perhaps latin...or perhaps a language that hasn't even been created yet.
so it doesn't matter, because they're probably speaking a language at most remotely related to the english language.