How to Identify the Instances of Grammaticalization

In the process of grammaticalization, a lexical item changes into a grammatical one, or an already grammatical item acquires more grammatical properties. Efforts have been made to isolate the mechanisms and principles underlying or accompanying grammaticalization. In this article, such mechanisms and principles are thoroughly examined. It is worth noting that a concept subsumed under mechanisms by one scholar may be considered as a principle in another framework. To avoid this kind of confusion, here only the common principles and mechanisms accepted by most linguists are touched upon. Therefore, the principles presented in this article are based on the classic article of Hopper (1991) and the related mechanisms are those described by Wischer (2006). Examples, mostly from Persian language, are also provided for each principle or mechanism. A thorough understanding of these principles and mechanisms can help us to identify the instances of grammaticalization in language. This in turn gives us useful insights as to the nature of changes in language. The availability of texts belonging to different periods is of great help in identification of instances of grammaticalization. However, here we show that by a good understanding of (especially) the principles of grammaticalization, one can rather easily identify the instances of grammaticalization even in those languages without a written tradition.