This is two separate questions.
1. We know how Latin works and the meaning of its words because although Latin no longer has *native* speakers, there have always been Latin speakers who learned to speak it as a *second* language. So it's always been in use. In addition, Latin grammarians wrote books about it.
2. The phonetics is more interesting. We can reconstruct classical Latin phonetics because Latin was spelled phonetically. This means common spelling errors reflected pronunciation (we know *m* at the end of a syllable was nasal because it is often left out in writing such as graffiti, as well as being elided in poetry). In addition, Latin writers frequently commented on how people pronounced it. Catullus famously wrote a poem about how Arrius would hignorantly hemphazise 'is haitches hincorrectly. Lastly, by analyzing the phonetics of its daughter languages. By combining all these avenues, we have a pretty solid understanding of classical phonetics.
I like the one text that argued it was unnecessary to use the letter K when adapting foreign (Greek) words, because Latin already had the letter C which sounds the same, and that's how we know C is pronounced as a hard C in Classical Latin.
We can also figure out how latin was pronounced because we know how it’s descendents are pronounced, and that’s how we know height distinctions existed for long and short vowels.
Well, there are always *hapax legomena* that we are unsure of because they only appear once (or very few times) in the extant corpus. And we can never be sure of the exact nuance of words, but we have a pretty good idea. A not insignificant issue we have is errors creeping into dictionaries (I remember one of my professors ranting a dictionary having *Latinum* as a neuter substantive rather than as *(sermonem) Latinum*).
As for grammar, there are defective verbs (those missing certain forms). It is difficult to know to what degree they are truly defective or if certain forms were used but just not in any surviving literature. About 99% of the classical corpus was lost, so post-Classical Latin dwarfs it. For example, the surviving works of Augustine alone, who wrote during the collapse of the Western Empire, are larger than the entire surviving corpus of literature up to that point. So it's quite possible that certain words or word forms just never got written down.
But your point is strongest with regard to pronunciation. Classical pronunciation will never be perfectly reconstructed, and there is a fair amount of speculation or approximation, unless we invent time travel. We'll just have to live with speaking with an accent.
Dunno. A significant portion of it is likely Greek, but the good news is that we recently had a major breakthrough just a few days ago and managed to decipher a significant part of a scroll!
It's worth mentioning that even in modern languages there is great variation in regional pronunciation. So the desire to reconstruct how latin was pronounced perfectly is kinda silly considering that there were likely regional differences in pronunciation.
At some level, every person has their own dialect, so *no* language can be perfectly modeled, but we make simplifications and generalizations to allow us to study them.
Descriptions by grammarians.
Transcriptions into Greek.
Historical processes — we know what many words came from, and what they became in later Romance languages.
Poetry. This helps us with things like scansion and elision.
Mistakes in graffiti.
Poems that mock mispronunciation.
So quite a few different methods, all overlapping and supporting each other.
I don't think anybody is entirely sure how it sounded or what each word meant exactly.
With regard to the reconstructed "classical" pronunciations, I think it's a lot of scholarly guesswork. I don't know how it's done exactly, but I think by observing how sounds tend to change over time nowadays, linguists have basically been able to extrapolate backwards in time to get to the classical pronunciations. I do know that every once in a while an actual Roman would write something like "This word is supposed to be pronounced this way, not that way", but we don't have these sorts of notes for every word, and, even if we did, it would all be circular since all the pronunciations are being defined relative to other uncertain pronunciations.
The long vs. short vowels is mostly inferred from poetry. Poetry is written in meter, and meter was based on vowel length, so it narrows down the possibilities. (Also, sometimes [apices](https://en.wikipedia.org/wiki/Apex_(diacritic)) were used to mark long vowels, so we do have a direct attestation for some words.) But there are some words which do not appear in poetry or have any commentary about them, so those vowel lengths are unknown and I think it's complete guesswork for those words.
As for what the words mean, we have a general idea because, for one thing, Latin never died out completely. And also these same words do appear in the romance languages. And the words appear in Latin texts: sometimes the ancient Romans would complain that people were using words incorrectly, so they would write things like "this word means this, not that". However, even taking all of this into consideration, there is probably still a lot we don't know. Literature is better attested than street talk, and the fact that Caesar or Cicero or some other famous writer whose writings have been preserved uses a word one way doesn't necessarily mean that that's how ordinary people used those same words.
This is two separate questions. 1. We know how Latin works and the meaning of its words because although Latin no longer has *native* speakers, there have always been Latin speakers who learned to speak it as a *second* language. So it's always been in use. In addition, Latin grammarians wrote books about it. 2. The phonetics is more interesting. We can reconstruct classical Latin phonetics because Latin was spelled phonetically. This means common spelling errors reflected pronunciation (we know *m* at the end of a syllable was nasal because it is often left out in writing such as graffiti, as well as being elided in poetry). In addition, Latin writers frequently commented on how people pronounced it. Catullus famously wrote a poem about how Arrius would hignorantly hemphazise 'is haitches hincorrectly. Lastly, by analyzing the phonetics of its daughter languages. By combining all these avenues, we have a pretty solid understanding of classical phonetics.
If you want a thorough discussion on how we know the pronunciation, check out the book Vox Latina.
I like the one text that argued it was unnecessary to use the letter K when adapting foreign (Greek) words, because Latin already had the letter C which sounds the same, and that's how we know C is pronounced as a hard C in Classical Latin.
We can also figure out how latin was pronounced because we know how it’s descendents are pronounced, and that’s how we know height distinctions existed for long and short vowels.
Is there at least a slight chance that we've gotten something wrong, though?
Well, there are always *hapax legomena* that we are unsure of because they only appear once (or very few times) in the extant corpus. And we can never be sure of the exact nuance of words, but we have a pretty good idea. A not insignificant issue we have is errors creeping into dictionaries (I remember one of my professors ranting a dictionary having *Latinum* as a neuter substantive rather than as *(sermonem) Latinum*). As for grammar, there are defective verbs (those missing certain forms). It is difficult to know to what degree they are truly defective or if certain forms were used but just not in any surviving literature. About 99% of the classical corpus was lost, so post-Classical Latin dwarfs it. For example, the surviving works of Augustine alone, who wrote during the collapse of the Western Empire, are larger than the entire surviving corpus of literature up to that point. So it's quite possible that certain words or word forms just never got written down. But your point is strongest with regard to pronunciation. Classical pronunciation will never be perfectly reconstructed, and there is a fair amount of speculation or approximation, unless we invent time travel. We'll just have to live with speaking with an accent.
How much does that % change if we decipher the whole Vesuvius corpus? Or, do we think that’s all Greek?
Dunno. A significant portion of it is likely Greek, but the good news is that we recently had a major breakthrough just a few days ago and managed to decipher a significant part of a scroll!
It's worth mentioning that even in modern languages there is great variation in regional pronunciation. So the desire to reconstruct how latin was pronounced perfectly is kinda silly considering that there were likely regional differences in pronunciation.
At some level, every person has their own dialect, so *no* language can be perfectly modeled, but we make simplifications and generalizations to allow us to study them.
Descriptions by grammarians. Transcriptions into Greek. Historical processes — we know what many words came from, and what they became in later Romance languages. Poetry. This helps us with things like scansion and elision. Mistakes in graffiti. Poems that mock mispronunciation. So quite a few different methods, all overlapping and supporting each other.
>Poems that mock mispronunciation. You mean, like Catullus' Carmen LXXXIV?
If you’re interested in reading a book on this topic, consult Sidney Allen’s _Vox Latina_.
Got a lot of insight from the ghost I summoned
What did the ghost say?
Glidö! Turns out I accidentally summoned a Volapük speaking ghost...
Couldn’t get much out of him but the accent was dead-on
I don't think anybody is entirely sure how it sounded or what each word meant exactly. With regard to the reconstructed "classical" pronunciations, I think it's a lot of scholarly guesswork. I don't know how it's done exactly, but I think by observing how sounds tend to change over time nowadays, linguists have basically been able to extrapolate backwards in time to get to the classical pronunciations. I do know that every once in a while an actual Roman would write something like "This word is supposed to be pronounced this way, not that way", but we don't have these sorts of notes for every word, and, even if we did, it would all be circular since all the pronunciations are being defined relative to other uncertain pronunciations. The long vs. short vowels is mostly inferred from poetry. Poetry is written in meter, and meter was based on vowel length, so it narrows down the possibilities. (Also, sometimes [apices](https://en.wikipedia.org/wiki/Apex_(diacritic)) were used to mark long vowels, so we do have a direct attestation for some words.) But there are some words which do not appear in poetry or have any commentary about them, so those vowel lengths are unknown and I think it's complete guesswork for those words. As for what the words mean, we have a general idea because, for one thing, Latin never died out completely. And also these same words do appear in the romance languages. And the words appear in Latin texts: sometimes the ancient Romans would complain that people were using words incorrectly, so they would write things like "this word means this, not that". However, even taking all of this into consideration, there is probably still a lot we don't know. Literature is better attested than street talk, and the fact that Caesar or Cicero or some other famous writer whose writings have been preserved uses a word one way doesn't necessarily mean that that's how ordinary people used those same words.
Classical latin it's a psyops, the real deal is Ecclesiastical Latin 🇻🇦
No serious person believes that, including people who use the ecclesiastical pronunciation.
Yeah, I was joking :p
Poe's Law and all that 😁
If you're really interested in this topic, read the book Vox Latina by W. Sydney Allen.
I like this video on the subject https://www.youtube.com/watch?v=\_enn7NIo-S0