Merge

Merge (usually capitalized) is one of the basic operations in the Minimalist Program, a leading approach to generative syntax, when two (adjacent) syntactic objects make up a new syntactic unit. Essentially, it is a manifestation of recursion, which many scholars claim to be a fundamental characteristic of language and mind in general, or, as Noam Chomsky (1999) puts it, Merge is "an indispensable operation of a recursive system ... which takes two syntactic objects A and B and forms the new object G={A,B}" (p. 2).

In the Minimalist Program Merge is triggered by feature checking, e.g. the verb "eat" selects the noun "cheesecake" because the verb has an uninterpretable N-feature [uN] ("u" stands for "uninterpretable") which must be checked (or deleted), due to full interpretation. By saying that this verb has a nominal uninterpretable feature we rule out such ungrammatical constructions as *eat beautiful (the verb selects an adjective). Schematically it can be illustrated as:

  
          V
  ________|_________
 |                 |
eat [V, uN]   cheesecake [N]

Chomsky (2001) distinguishes between external and internal Merge: if A and B are separate objects then we deal with external Merge; if either of them is part of the other it is internal Merge.

In other approaches to generative syntax, such as Head-driven phrase structure grammar and Lexical functional grammar, there is no precise analogue to Merge. However, in these theories, feature structures are used to account for many of the same facts.

References

• Adger, D. (2003). Core syntax: A Minimalist approach. Oxford: Oxford University Press. ISBN 0199243700. 
• Chomsky, N. (1999). Derivation by phase. Cambridge, MA: MIT. 
• Chomsky, N. (2001). Beyond explanatory adequacy. Cambridge, MA: MIT.