In comparing the uses of functional vocabulary and its lexical ancestors, we primarily notice that functional vocabulary is structurally syntactically different from its lexical ancestor. This statement requires a more detailed description but, for now, let us just say that functional vocabulary adopts novel syntactic roles that its lexical counterpart does not, such as the auxiliary role of have.
We think that the rearrangement in the use of functional vocabulary is not unlike the rearrangement of constituents in the phase transitions of material constituents such as H2€O molecules in water or ice.
With Jennings' account of scope misapprehension we also conclude that the misunderstanding in the use of functional vocabulary is a powerful motivator in the shareability of language. As we demonstrate in the The Physics of Language, the dynamics that lead to the misunderstanding in the use of functional vocabulary is present for all vocabulary. This feature is also responsible for increasing the flexibility in the use of vocabulary and, in turn, for its propagation across a population. Loosely, we think that this kind of dynamic is similar to an increase in the available energy of a system such as H2€O. The energy available to molecules in water allows them to move about more freely than in its solid state of ice.
In subsequent chapters we describe how the dynamics of language evolution parallels the dynamics of phase transitions in materials.