Do Language Models Know Theo Has a Wife? Investigating the Proviso Problem

Tara Azin, Daniel Dumitrescu, Diana Inkpen, Raj Singh


Abstract
We investigate how language models handle the proviso problem, an unresolved issue in pragmatics where presuppositions in conditional sentences diverge between theoretical and human interpretations. We reformulate this phenomenon as a Natural Language Inference task and introduce a diagnostic dataset designed to probe presupposition projection in conditionals. We evaluate RoBERTa, DeBERTa, LLaMA, and Gemma using explainability analyses. The results show that models broadly align with human judgments but rely on shallow pattern matching rather than semantic or pragmatic reasoning. Our work provides the first computational evaluation framework for the proviso problem and highlights the need for diagnostic, multi-method approaches to assess pragmatic competence and context-dependent meaning in language models.
Anthology ID:
2026.lrec-main.155
Volume:
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Month:
May
Year:
2026
Address:
Palma de Mallorca, Spain
Editors:
Stelios Piperidis, Núria Bel, Henk van den Heuvel, Nancy Ide, Simon Krek, Antonio Toral
Venue:
LREC
SIG:
Publisher:
ELRA Language Resource Association
Note:
Pages:
1977–1988
Language:
URL:
https://preview.aclanthology.org/ingest-lrec/2026.lrec-main.155/
DOI:
Bibkey:
Cite (ACL):
Tara Azin, Daniel Dumitrescu, Diana Inkpen, and Raj Singh. 2026. Do Language Models Know Theo Has a Wife? Investigating the Proviso Problem. International Conference on Language Resources and Evaluation, main:1977–1988.
Cite (Informal):
Do Language Models Know Theo Has a Wife? Investigating the Proviso Problem (Azin et al., LREC 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-lrec/2026.lrec-main.155.pdf