Linguistics: I-Language and E-Language Noam Chomsky introduced the I-Language and E-Language to refer to internal/internalised and external/externalised language respectively where internal and external are to be interpreted with reference to the individual speaker. So, the linguistic knowledge that is in the mind of the speaker is I-Language whilst the observable linguistic output (sentences, songs, texts etc.) is E-Language. Conceptually, this differentiates the object of study of Chomskyan linguistics (namely I-Language) from that of other disciplines such as philology and discourse analysis etc. which focus on E-Language. ittedly, it is not always easy to delineate the two in practice, but the terminology should help in clarifying roughly which aspect of language is under consideration. Such clarification should hopefully help people avoid clashes resulting from terminological confusion. Every fluent individual in a language community has an I-Language. As such, every individual can produce a potentially infinite E-Language. E-Language is thus epiphenomenal; it is the result of I-Language. ELanguage does not (and under this conception, cannot) exist independently of I-Language. Chomskyan linguistics thus seeks to study I-Language since it is the primary phenomenon. Whilst it is appropriate for other disciplines to focus on E-Language, this would not be appropriate for the aims and goals that Chomsky proposes. However, having said that, the only way to study I-Language is via E-Language! ELanguage is I-Language made visible (assuming no performance errors, of course!). In a speech community (although note that speech is not the only form of E-Language), what we have is effectively a population of individual I-Languages which overlap. The output of all these I-Languages gives us the ELanguage of the community which is usually the stage at which we give a name to it, e.g. English, French, Mandarin etc. Communal E-Languages are notoriously hard to define – consider Dutch and German. Both are considered distinct ‘languages’ but there is a dialect continuum between the Netherlands and and no distinct point at which someone on one side can be said to be speaking Dutch and someone on the other to be speaking German. By looking at the E-Language of a particular individual, we avoid the ‘noise’ of a communal E-Language. In fact, if we want to study I-Language we can only look at an individual’s ELanguage since it is meaningless to talk of an individually internalised I-Language above the level of the individual. Ideally, we would end up with many descriptions of individual I-Languages. At this point, we could start to compare them. Comparison involves looking for points of variation as well as points of overlap. How does an I-Language from one village differ from an I-Language in a neighbouring village? How does the ILanguage of a so-called English-speaker differ from that of a so-called Mandarin-speaker? As can be seen, this is not only useful for studying dialect continua and language change, but also for studying what is universal to human languages in general.

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