Syntactic Change In Progress?

For several years I have been recording examples of what appeared to me to be syntactic change in progress in English. This paper is a report on the examples collected. I group the examples into three categories: inflectional forms of verbs, grammaticalization (or semantic bleaching), and verb recentralizations. The principal conclusion is that it is very difficult to determine whether a particular case does indeed represent syntactic change in progress. In fact, there seem to be no clear criteria to establish (1) whether or not a given instance of language use represents a linguistic change at all, (2) whether a particular change has already occurred or is still in progress, and (3) just which changes should be counted as syntactic. But this is not a satisfactory situation. How can there be a science of linguistic change which does not attempt to explain how the transition from one discrete language-state to another is accomplished?