Maximal projection

Government and binding (GB, GBT) is a theory of syntax and a phrase structure grammar (as opposed to a dependency grammar) in the tradition of transformational grammar developed principally by Noam Chomsky in the 1980s. This theory is a radical revision of his earlier theories and was later revised in The Minimalist Program (1995) and several subsequent papers, the latest being Three Factors in Language Design (2005). Although there is a large literature on government and binding theory which is not written by Chomsky, Chomsky's papers have been foundational in setting the research agenda.

The name refers to two central subtheories of the theory: government, which is an abstract syntactic relation applicable, among other things, to the assignment of case; and binding, which deals chiefly with the relationships between pronouns and the expressions with which they are co-referential. GB was the first theory to be based on the principles and parameters model of language, which also underlies the later developments of the minimalist program.

The main application of the government relation concerns the assignment of case. Government is defined as follows:

A governs B if and only if

Governors are heads of the lexical categories (V, N, A, P) and tensed I (T). A m-commands B if A does not dominate B and B does not dominate A and the first maximal projection of A dominates B, where the maximal projection of a head X is XP. This means that for example in a structure like the following, A m-commands B, but B does not m-command A:

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