Chomsky sets out to answer three questions in Knowledge of Language. First, what constitutes knowledge of language? Second, how is knowledge of language acquired? Finally, how is knowledge of language put to use? In order to answer these questions, Chomsky first lists six sentences to demonstrate the inadequacy of the traditional ideas that language is a relationship between a string of words and meanings and that people learn language by example and analogy:
1. I wonder who the men expected to see them.2. The men expected to see them.3. John ate an apple.4. John ate.5. John is too stubborn to talk to Bill.6. John is too stubborn to talk to.
Example and analogy fail to explain how people know that “the men expected to see them” has two different meanings in the first two sentences. The sentences are almost identical in words and structure, but in the first an unknown person is expected to see the men, while in the second the men expect to see unknown persons. In the fourth sentence, if “apple” is omitted, the meaning that John ate something is still implied, but in the sixth sentence, the omission of “Bill” does not imply that Bill is too stubborn to talk to someone. Therefore, the omission in the sixth sentence cannot be understood by analogy with the omission in the fourth sentence. Chomsky points out that at an early age children understand sentences like these. Furthermore, although almost no one could explain these structures to foreign students of English, they can learn them.
Chomsky notes that similar problems of structure and comprehension exist in other languages. Therefore, there must be innate brain functions that allow people to produce and understand such sentences. Also, Chomsky makes the point that knowledge of a language and use of a language are not synonymous. People with similar knowledge differ in their ability to use it, and impairment in ability to use it does not necessarily mean impairment in knowledge. To answer his first and second principal questions, Chomsky limits himself to the nature of the brain functions, which he calls universal grammar, and to a person’s internal knowledge of a language, which is what he means by the word “language.” He does not attempt to answer the third question (except indirectly, inasmuch as internal language can be studied only as it is expressed in use) until the final chapter on “Orwell’s problem.” By limiting the definition of language to these mental concepts, Chomsky can define knowledge of language as states of mind, which can be studied as parts of psychology and, ultimately, biology. The purpose of Knowledge of Language is to identify these brain functions, or capacities, and their parameters in order to develop the production and comprehension of various languages. He calls the pre-language state “SO” and the language-knowing state “SL.”
The main problem of identifying the universal grammar capacities of the mind is that the principles of the SO state must be general, or inclusive, enough to account for the variety of languages but restricted enough to account for the fact that a specific language can be learned. What Chomsky calls the SO capacities are...
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