Chapter 1. The influence of social, cultural, and natural factors on language structure
This book is an attempt to give an overview of how language interacts with its environment, or better, how actual linguistic structure is formed, changed and influenced by different aspects of the human environment. The focus is mainly on effects of the extra-linguistic environment on the actual grammatical structure of languages; we will leave influences on other linguistic subsystems such as phonology, the lexicon, and discourse structure to the efforts of other researchers.The underlying assumption of this entire volume is that linguistic structure is not only shaped by how speakers interact with each other and with the world they live in, but also by external forces that are outside the control of individual speakers or speech communities. One might call it natural selection in grammar, were it not for the fact that it is not entirely clear whether biological and linguistic change operate along the same real-world principles, or whether any correspondences are much more superficial.