Editing Universal grammar (section)

== Developments ==
In 2017, Chomsky and Berwick co-wrote their book titled ''Why Only Us,'' where they defined both the minimalist program and the strong minimalist thesis and its implications, to update their approach to UG theory. According to Berwick and Chomsky, "the optimal situation would be that UG reduces to the simplest computational principles which operate in accord with conditions of computational efficiency. This conjecture is ... called the Strong Minimalist Thesis (SMT)."<ref name=chober>{{cite book |last1=Chomsky |first1=Noam |last2=Berwick|first2=Robert C.|date=12 May 2017|title=Why Only Us?|publisher=[[MIT Press]] |isbn= 9780262533492}}</ref>{{rp|94}} 

The significance of SMT is to shift the previous emphasis on a universal grammar to the concept that Chomsky and Berwick now call "merge". "Merge" is defined there as follows:<blockquote>Every computational system has embedded within it somewhere an operation that applies to two objects X and Y already formed, and constructs from them a new object Z. Call this operation Merge.</blockquote> SMT dictates that "Merge will be as simple as possible: it will not modify X or Y or impose any arrangement on them; in particular, it will leave them unordered; an important fact. Merge is therefore just [[Set (mathematics)|set]] formation: Merge of X and Y yields the set {X, Y}."<ref name=chober/>{{rp|98}}