Out of the mouths of babes...

What is the nature versus nature debate?

Not restricted to the area of language acquisition, the nature versus nurture debate questions why humans behave the way we do. Is our genetic make-up at birth the keystone to our abilities and inabilities? Or, are we born 'clean slates', with no built-in cognition - our successes and failings in life resulting only from experiences and sensory perception of the outside world gathered gradually over time. These are the two extreme views held by many intellectuals, the truth possibly lying somewhere between the two.

Biology and environment

Those with a nativist standpoint hold that children are born 'pre-programmed' for first language acquisition, reasoning that language is hugely complex yet children are able to start babbling from a very young age and develop this into coherent structures extremely quickly. That children should have an innate knowledge of grammar is supported by the utterances they produce at an early age. The errors they both do and do not make are interesting in that the order of words is correct. A child may say 'daddy go' to mean 'daddy is going' but would never say 'go daddy', showing a precocious mastery of the basic rules of syntax. The systematic application of regular past tenses rules is another frequent occurrence:

He taked my toy.

I falled down.

She eated it.

Non-nativist theorists conclude that children's language acquisition comes about as a result of imitation and re-inforcement, believing that without outside stimulus, language acquisition would not be possible. And this is to a large extent true. Adults play an important role by speaking to children in an often slow, grammatical and repetitious way. Children assimilate the language they are exposed to and experiment with utterances which gradually become more complex and accurate.

However, if nurture were solely responsible for language acquisition, how is it that children produce utterances that are completely novel and have never been taught to them or spoken to them by an adult?

Words and sentences are not just stored by a child and repeated parrot fashion. They must learn words but also understand them and produce novel sentences with them. To do this, they must learn rules which allow them to speak creatively. These rules are not taught to them explicitly; they look for and learn grammatical rules from nothing more than the utterances they hear. Errors and adjustments are made as their language develops until it matches that of the adult speaker population.

Critical age

There is an hypothesis that a critical age exists for language acquisition. Children master language between the ages of 2 to 7. This suggests the acquisition of first language is an innate capacity of human beings resulting from being 'pre-wired' for language.

The implication is that if a child hears a language, when they reach this critical period they will learn it perfectly. If this is true, any child not exposed to language by this crucial age, will never fully master language and, in particular, the grammatical structures. This conclusion is supported by evidence from cases involving feral children, children who have lived in confinement and isolated from human contact from a very young age, where efforts to teach them language have resulted in varying degrees of success .

After this critical period, it becomes increasingly more difficult for humans to learn languages, and might explain why second-language acquisition is often more difficult the older you get.

Though not conclusive, the suggestion that language is an innate capacity of human beings which is acquired during a critical period at an early age is compelling.