Language Lost and Found

Languages which are taught and studied are usually divided into two major cohorts:

1. Living Languages, such as English, Spanish and Chinese
2. Dead Languages, such as Latin, Ancient Greek and Sanskrit

Latin, Greek and Sanskrit are examples of languages which no longer have any native speakers but are still regularly taught in schools and universities across the world. These can be contrasted with languages, such as Manx from the Isle of Man, which aren’t studied  and no longer have any mother tongue speakers. To this group of languages we can also add the huge number of indigenous languages of South America and Australia, where a language or dialect is lost almost on a daily basis.

To this list of dead but still taught languages we can add Old English, which is often taught to those studying English literature and Historical Linguistics. Either way, compulsory reading usually consists of the classics, such as the Beowulf saga, where the language is dissected and analyzed either for literary or linguistic purposes.

Of course, to be able to appreciate the prose of Beowulf, you first have to learn Old English. Given that Old English is merely an older version of English, why is it treated as a separate language which is taught with its own dictionaries, grammatical rules and pronunciation?