The Developmental Dynamic Of Generalisation — Abstractness — Metaphor

Halliday & Matthiessen (1999: 618):

The developmental dynamic of "generalisation — abstractness — metaphor" provides the semiotic energy for the grammar, enabling it to serve as the powerhouse for construing experience in the form of scientific knowledge. Presented in this very sketchy fashion the movement may seem catastrophic and discontinuous; but this is misleading. Rather, it is a steady progression, marked by three periods of more rapid development at the transitions: 

from protolanguage to language (generalisation, associated with bipedal motion), 

from commonsense (spoken) language to written language (abstractness: the move into primary school), and 

from non-specialised written language to technical language (metaphor the move into secondary school). 

There is a clear grammatical and semantic continuity between the various versions of experience, which we can bring out by analysing the grammar of particular instances (such as those cited above). At the same time, the ontogenetic perspective shows that in fact our experience is being ongoingly reconstrued and recategorised as we grow from infancy to maturity.  

This is the outcome of processes taking place in human history — evolutionary events that are at once both material and semiotic, and that cannot be reduced to either purely physical processes driven by technology or purely discursive processes driven by ideology. 

There is no point in asking whether the ideation base of our technologised natural languages necessarily had to evolve the way it did. But it is extremely pertinent to ask, given the enormous demands now being made on both the material and the semiotic resources of the human species, what the options are for the way it may evolve in future.