Evaluate Chomsky's contribution to linguistics in terms of 'competence and performance'.

Noam Chomsky is the famous American linguist. He is the most dominant linguist of present time. He has put aside the traditional concepts of language viewed as a set of rules. He believes that the ideal speaker-hearer knows the language of that community perfectly. That is why, the knowledge of the ideal speaker-hearer is more important to him than the descriptive rules of a language.
Chomsky, in his revolutionary book Aspects of the Theory of Syntax (1965), has made a fundamental distinction between the knowledge of a language and its actual use. In order to explain his views about language, he has used two terms— (1) competence and (ii) performance.
Competence (Grammatical sense):
Linguistic competence, according to Chomsky, is the ideal speaker-hearer knowledge about a language. This knowledge is possessed by an ideal speaker-hearer. This knowledge helps to judge about a language. For example, an ideal speaker-hearer can judge which sentences are correct and which are not. In sum, linguistic competence is grammatical competence of an ideal speaker-hearer.

Chomsky describes 'competence' as an idealized capacity that is located as a psychological or mental property (which naturally develops within us). This capacity or ability allows the speaker to understand the underlying rules of a language. Hence, competence allows the user to make general statements about the language. For this reason, the theory of linguistic competence is called grammar of a language. However, it is like the grammar taught in schools.

Performance (Usage):
By 'Performance' Chomsky means 'the use of language in concrete situation'. "Thus, it is the actual record of speech production. Thus performance largely depends on different contexts and settings where the language is actually used. For