TLLM 2026

Modality in Logic and Language

5th Tsinghua Interdisciplinary Workshop on Logic, Language and Meaning

April 3–5, 2024, Tsinghua University, Beijing

The website for this year’s conference is available at: TLLM 2026
For previous years’ websites, please visit: TLLM

The study of modality in logic is as old as logic itself. Modern propositional and predicate logic replaced notions like ‘necessary’ and ‘possible’, traditionally used to define what it means for a proposition to follow from other propositions, by quantification over ways to interpret the non-logical symbols of the language. But the study of reasoning with the modalities themselves has continued in logic, with the modern tools now available. Early syntactic studies of systems for ‘strict implication’ gave way to possible worlds style semantics in the hands of pioneers like Carnap, Kanger, Hintikka, Kripke, and others, which now provides a standard framework for the logical study of modality. This framework has been applied to systems of logic where oA is meant to capture readings, besides ‘A is necessary’, like ‘A will always be the case, A holds after a certain program execution step, A is provable, obligatory, justified, probable, believed/known by an agent’, etc. Today, the vast area of philosophical logic studies all kinds of ‘intensional’ notions, using formal languages and well-established mathematical tools. In philosophy too, the discussion about the nature of possible worlds and their use for various modalities, initiated by Lewis, Stalnaker, Kripke, Fine, Williamson, and others, is still a very active area of research.

In parallel, and sometimes in cooperation, linguists have studied the syntactic and semantic behavior of modals in natural languages. Modals, together with tense, enable us to displace from the actual here and now, embodying one of Hockett’s design features of natural language: displacement. Natural language also abounds in modal expressions and constructions. In English for instance, we encounter at least auxiliaries, verbs, adverbs, nouns, adjectives, and conditionals that convey modal meanings. On the other hand, languages vary significantly in how they express and categorize modal meanings (as explored in the works of Rullmann, Matthewson, Deal and many others). The rich empirical landscape provides linguists – building on Kratzer’s pioneer work – with opportunities to study the range of modal concepts expressible in natural language, how they are expressed, the theoretical frameworks and logical tools required to analyze them, the processes by which they are acquired, and so on.

The TLLM workshops aim to bring together logicians, philosophers, and linguists around a specific theme of common interest. For the 2026 event, the theme is unusually wide, and we welcome contributions on any general or particular aspect of the modalities in logic or language. Below are just a few examples of possible topics for this workshop.

• Foundations and semantics of modality: E.g. Kripke/neighborhood/possibility/topological/ game-theoretic/inquisitive/team semantics.
• Proof theory for modal logic: E.g. sequent/natural deduction/labelled/circular/display/ deep inference systems.
• Epistemic and doxastic logics.
• Deontic logic, norms and preference.
• Modality in natural language: E.g. epistemic/deontic/dynamic modals; weak necessity and gradability; syntax of modals; semantic-pragmatic interface; cross-linguistic typology; experimental and corpus studies.
• Non.classical perspectives on modality: E.g. intuitionistic/linear/relevant/paraconsistent/ modal bilattice frameworks; bilateralist accounts.
• Modality in computation, verification, and AI: E.g. KR with modalities; causal and probabilistic modal models; LLMs and modal reasoning (benchmarks, neurosymbolic methods, toolkits).
• Modality and other intensional categories: e.g. modality and tense; modality and evidentiality; modality and mood.
• The processing and acquisition of modal expressions in natural languages

Contributed Papers

We invite submissions of 2-page abstracts (including references) on any of the broad themes related to the modality in logic and language as suggested above. After a review procedure, authors of accepted abstracts will have the opportunity to present their papers at the workshop, either as a contributed talk or in the poster session. The poster session is intended to provide an informal setting for discussion and to encourage participation from early-career researchers and students. After the workshop, a volume of full papers (properly refereed) will be published in the Springer LNCS – FoLLI series. Details on submission of full papers will follow.

The workshop will take place on site at Tsinghua University, Beijing.

Sponsors

• The Joint Research Center for Logic, Tsinghua University
• Department of Philosophy, Tsinghua University
• Department of Foreign Languages and Literatures, Tsinghua University