Binding theory

In linguistics, binding is the distribution of anaphoric elements (pronouns and other pro-forms). A pronoun (a "bindee") usually has an antecedent (a "binder") in context. The goal of binding theory is to identify the syntactic relationship that can or must hold between a given pronoun or noun and its antecedent (or postcedent), e.g. John_i said he_i would help vs. *He_i said John_i would help (the second sentence is not possible if he is intended to mean John).

The idea that there should be a specialized, coherent theory dealing with this sort of phenomena originated in work in transformational grammar in the 1970s. This work culminated in government and binding theory in the 1980s. The binding theory that became established at that time is still considered a reference point, though its validity is no longer accepted.

Many theories of syntax now have a subtheory that addresses binding phenomena. These phenomena exist in all languages, although the behavior of binding can vary in interesting and nuanced ways across languages, even across languages that are closely related.

The following sentences illustrate some basic facts of binding. The words that bear the index i should be construed as referring to the same person or thing.

These sentences illustrate some aspects of the distribution of reflexive and personal pronouns. In the first pair of sentences, the reflexive pronoun must appear for the indicated reading to be possible. In the second pair, the personal pronoun must appear for the indicated reading to be possible. The third pair shows that at times a personal pronoun must follow its antecedent, and the fourth pair further illustrates the same point, although the acceptability judgement is not as robust. Based on such data, one sees that reflexive and personal pronouns differ in their distribution and that linear order (of a pronoun in relation to its antecedent or postcedent) is a factor influencing where at least some pronouns can appear. A theory of binding should be in a position to predict and explain the differences in distribution seen in sentences like these. It should be in a position to answer questions like: What explains where a reflexive pronoun must appear as opposed to a personal pronoun? When does linear order play a role in determining where pronouns can appear? What other factor (or factors) beyond linear order help predict where pronouns can appear?

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