Interesting discussion. It's true that we can trace the changes in languages. However, it is very difficult to be sure of the pronunciations. Put it this way. Do you know how I pronounce potato? It may have been written the same way for a few hundred years, but the contemporary reader is no more certain of the way an individual pronounced the word 50 or even 25 years ago. "Brooklynese" is a good example; how do you say "toilet" or "oil"? Is it "terlet" and "earl"?
The other issue is that no ancient language was written in a purely phonetic script that we know would be consistent with the one that we use now. So, it'd be possible to take reasonable guesses. And it's even possible to use those guesses to have a better idea of what, say, Middle English (Chaucer, not Shakespeare) sounded like. E.g., today, no one says "ka-nict" for "knight" or "ka-neef" for knife
And, we wouldn't write "hwale" for whale, though that might be the way an Anglo-Saxon would have written it.
Of course, other issues, like the lack of vowels or of sounds we don't use or were used silently then. Otoh, we have a great deal of knowledge about written language --apart from articulation or pronunciation. You know, guys like Grimm, et al, who cataloged the sound shifts from Indo-European to Germanic to English, etc. So, we know that our "father" and the Latin "pater" and German "vater" have the same roots. Buuut, how do you pronounce "pater"?
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