Compositionality

Languages contain meaningful expressions built from other meaningful expressions. On the traditional view, the meaning of a complex expression is determined by its structure and the meanings of its constituents. Once the meanings of the constituents and their mode of combination are fixed, the meaning of the whole is fixed. This is the principle of compositionality, a fundamental presupposition of most contemporary work in semantics. Proponents of compositionality emphasize the productivity and systematicity of the linguistic competence of human beings. Humans can understand a large—perhaps infinitely large—collection of complex expressions even when first encountered. Humans who understand some complex expressions can usually also understand other expressions that result from recombining their constituents. Compositionality is supposed to feature in the best explanation of these phenomena. Opponents of compositionality point to cases when meanings of larger expressions seem to depend on the intentions of the speaker, on the linguistic environment, or on the setting in which the utterance takes place without their parts displaying a similar dependence. They try to respond to the arguments from productivity and systematicity by insisting that the phenomena are limited, and by suggesting alternative explanations.