Hussar
Legend
Linguistic drift can be minimized with things like audio recordings and dictionarys. They haven't existed for most of the last 2000 years.
True, but, language drifts very quickly. Compare Parisian French with Quebecois - two languages that started out the same, but, have drifted considerably in just a couple of hundred years.
And, what would really drive linguistic drift is specialization. The engineers might be able to read the technical manuals of their particular field, but, have no idea how to read the landing procedures manual. Or how to repair the hydroponics bay. That sort of thing. Technical jargon makes linguistic drift even worse.
And, sure, we can learn Latin, but, A. There's no guarantee that what you learn is actually correct and B. we can learn Latin because we have massive libraries of a couple of thousand years of translations to compare to. Again, in a small, closed society, likely stratified by work type, it's entirely possible that parts of the ship won't be able to communicate with each other.
I mean, good grief, it's hard enough talking to that IT guy now. Imagine after 500 years of linguistic drift.
