Three distinct components of pragmatic language use: social conventions, intonation, and world-knowledge-based causal reasoning

Real-life language comprehension frequently requires non-literal interpretation and inferences about speaker intent. What is the structure of these so-called pragmatic abilities? We applied a dimensionality reduction approach to a large behavioral dataset (776 participants, each completing an 8-hour battery of diverse non-literal comprehension tasks). By examining covariation in performance across tasks, we identified three interpretable components of pragmatic language use: adherence to social conventions, extracting meaning from intonation, and causal reasoning based on world knowledge. Thus, pragmatic language use is relatively low-dimensional cognitively, and its distinct components may a) draw on dissociable neural substrates, b) exhibit distinct developmental trajectories and differential susceptibility to genetic brain disorders, and c) be variably challenging for artificial intelligence systems.