Learning theory is as diverse as the research community itself, and nowhere is the concern to understand how the individual responds to the wash of experience with intelligence more debated and studied than in regard to child language acquisition and development. Language, as a symbolic tool, is an important factor of any child's overall development, and its acquisition by children has been studied by any number of researchers. Scholars share the conviction that key aspects of personality and ability are formulated in the earliest stages of life. They are more divided on whether and to what extent human intuition on one hand or heredity or environment play a role in a child's development of any knowledge, aptitude, or skill. Not infrequently, theories of language acquisition and development also appear to interpret competing theories in ways that serve the commenting theorist more than authentic theoretical clarity.
Language-development theory, in sum, is a matter of great dispute. Attempts to explain or criticize competing theories, as well as attempts to build on existing theory or create supposedly new theories, have had varying degrees of success at contributing to a coherent understanding of child language development. To isolate key issues affecting such understanding, and to suggest a way of approaching a theory of child language development with precision, is the aim of this paper.
In 1865, E.B. Tylor remarked that what distinguishes human from animal language is the fact that animals can make signs but do not know signs. He noted that a dog barks for the door to be opened, but "it is hard to say how far the dog's mind merely associates . . . barking and being let in, or how far it forms a conception like ours of what it is doing" (p. 123). Lower primates such as chimpanzees, passeriformes such as parrots, and aquatic mammals such as dolphins and whales acquire limited sets of genotypically conditioned response, and langu...