In
mathematics,
semantics, and
philosophy of language, the
principle of compositionality is the principle that the meaning of a complex expression is determined by the meanings of its constituent expressions and the rules used to combine them. This principle is also called
Frege's principle, because
Gottlob Frege is widely credited for the first modern formulation of it. However, the idea appears already among
Indian philosophers of grammar such as
Yaska, and also in
Plato's work such as in
Theaetetus. Besides, the principle was never explicitly stated by Frege, and it was arguably already assumed by Boole decades before Frege’s work.