The rise of discourse markers

Previous research has established that discourse markers differ in their development from other grammatical material. Nevertheless, the main view expressed in much of that research was that this development can be described most appropriately in terms of grammaticalization, even if an extended version of grammaticalization may be required. The book proposes a new perspective of the genesis of discourse markers. While admitting that grammaticalization plays  some role, it is argued that discourse markers are mainly the result of discourse-pramatic processing. This processing involves an operation called 'cooptation' whereby a given linguistic expression is transferred from the level of sentence grammar to that of discourse organization.