ABSTRACT
In Chapter 2, the internal structure of all major three-element sequences in phonology, morphology, and syntax was established for Modern English. This chapter brings the temporal dimension into the picture and addresses whether and how structure changes across time. The Structural Theory highlights two ways in which historical change might take place. One is a change in branching direction (i.e., from left-to right-branching or from right-to left-branching). The other way is made possible by the scalar nature of the model. As a language is not either totally flat or hierarchical, it is conceivable that it changes along this continuum (i.e., that it moves in the direction of more or less hierarchicalness without, however, changing its overall branching direction) There is an interesting relationship between the two types of change. A given language can only change its branchingdirection preference if it is (almost) completely flat. Flatness is, as it were, the gate from one branching direction to the other. A strongly hierarchical language cannot simply change its branching direction. Because branching direction relies on hierarchicalness, the former cannot change without the latter (though not vice versa).
