Page "Principle of compositionality" Paragraph 5

Scholars are also divided as to whether the principle should be regarded as a factual claim, open to empirical testing ; an analytic truth, obvious from the nature of language and meaning ; or a methodological principle to guide the development of theories of syntax and semantics.

The principle has been attacked in all three spheres, although so far none of the criticisms brought against it have been generally regarded as compelling.

Most proponents of the principle, however, make certain exceptions for idiomatic expressions in natural language.

( Szabó, 2012 )