The recent visit of my 20-month-old granddaughter, Abigail (or Abby-G as she calls herself), drew me a little afield of my core expertise—into acquisitional semantics. What follows amounts to a set of informed observations rather than a reliable argument.
Language acquisition begins at the age of 2, plus or minus 3-4 months. Before that age, chimpanzees can do pretty much whatever a human can do. When language acquisition sets in, however, humans rocket far, far beyond the communication skills of any other species. (Click here for the arguments.)
This puts Abby-G at an interesting stage of development: just at the onset of language acquisition but not quite there. At this point in her life her communication is primitive: she uses only single words, occasionally a two-word phrase that she has memorized but she cannot yet construct even simple phrases on the fly.
The experts tell us that as children begin to learn language, they look for one-one associations between linguistic sound (phonology) and meaning (semantics). They don’t expect couch and sofa to mean the same thing. I have serious doubts about this assumption but lets accept it as a working hypothesis. So what kind of associations do children make before they acquire language, the rules of grammar, that tell them how things are related?
In other words, how does Abby-G seem to be attaching meaning to sounds? She seems to be making the very simple one-one associations experts predict and chimpanzees do. However, the sounds associated with meanings are not always (grammatically) appropriate. For example, a playground is a “whe-e-e-e-e!”, to go somewhere” is car, and a train is a choo-choo. Abby-G associates sounds with activities involved with the objects as easily as she associates sounds with things as easily as she associates sounds with objects involved in activities. At this stage: no pattern, no guidance from grammar.
It is always fascinating to observe children struggling to sort out the semantic world. Before the language acquisition stage emerges in them, they use any kind of association they can imagine from whee for the playground to car for “let’s go”. I can hardly wait to see her acquire language: discovering grammatical categories and using them to assemble sentences. At that point grammatical categories like noun, verb, adjective, comparative, past tense appear out of nowhere in an explosion of knowledge that only one species has the privilege of enjoying and that be explained only in terms of innate knowledge. In other words, it is simply there when human children hit a certain stage of development.