1. Explaining similarities
Historical linguistics as a concept has come to be used in a number of ways. First, in referring to a discipline investigating the development of single languages from an earlier to a later point in time, e.g. two or more stages of Ancient Egyptian, the language of Pharaonic times, whose written records date back four and a half millennia, and which probably became extinct as a spoken language (known as Coptic) several centuries ago. A second way in which the term historical linguistics has come to be used is as a short hand for historical-comparative linguistics – more specifically the comparative study of genetically related languages, hence the alternative term genetic linguistics. This is the way in which the term is used in the present study. In historical-comparative linguistics, or simply comparative linguistics, one reconstructs “upstream”, i.e. one works backwards from today’s languages in order to establish genetic relationships and in order to reconstruct earlier stages by studying collateral relationships. Even though as a discipline historical (or dia-chronic) linguistics grew out of philology, one does not necessarily depend on written documents or texts in order to be able to reconstruct historical changes in languages, as should become clear from the following chapters. What is needed to begin with are solid analyses of individual languages. This chapter sets out to list a number of reasons why languages may manifest similarities in their lexical and grammatical structures. After a discussion of chance, sound symbolism, borrowing and shared inheritance, basic principles of the comparative method are explained. As a first step, these involve setting up sound correspondences between cognate roots in languages assumed to be genetically related, and reconstructing historical changes in these forms.