Historical linguistics (HL) is the branch of linguistics that is concerned with language change, especially over longer stretches of time. The two major questions that have occupied historical linguists can be formulated as follows. (i) How do languages change? (establishing the facts) (ii) Why do languages change the way they do? (the search for explanations). The answers that have been given, as all answers in linguistics, are at best partial, and reflect the specific biases of the schools or frameworks that have succeeded each other in the course of time.
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