#ModalLogic
People working on non-deterministic semantics flaunt that they can do modal logic without possible worlds. But do they have a theory modality?

Yesterday in Ghent I argued that they do. Thanks for the invite, I met many people who I cite, which now I can call colleagues.
#metaphysics #modallogic
October 18, 2025 at 8:44 AM
An explanation of what axioms and mathematical proofs really are. With a reference to my tool that helps exploring some of them.

#Logic #Axioms #Mathematics #ProofTheory #HilbertSystems #ModalLogic #Research #Software
What is the significance of the K-axiom in modal logic S5?
In normal modal logic S5, the K axiom says $\square (p \rightarrow q) \rightarrow (\square p \rightarrow \square q)$. First of all, is this an abuse...
math.codidact.com
April 9, 2024 at 8:28 AM
The separability problem for modal fixpoint formulas is PSpace‑complete on words and ExpTime‑complete on unrestricted and binary models, with TwoExpTime‑complete hardness when outdegree ≥3. https://getnews.me/complexity-of-separating-fixpoint-formulae-in-modal-logic/ #modallogic #complexity
September 30, 2025 at 10:22 PM
In this week's #blog I write briefly about a 2001 paper on designing lambda calculi for intuitionistic modal logic. https://blogs.fediscience.org/the-updated-scholar/2025/08/15/discussing-extended-curry-howard-correspondence-for-a-basic-constructive-modal-logic/ #logic #ModalLogic #ProofTheory […]
Original post on fediscience.org
fediscience.org
August 15, 2025 at 2:48 AM
Sharing an early poem of mine published in Soundings East!

#poetry #experimentalpoetry #avantgarde #micropoetry #modallogic #logic
January 27, 2024 at 12:33 AM
Ever debated what *must* be true for an argument to hold? Necessity in logic (Q2301186) sparked medieval scholastic clashes—Aquinas vs. skeptics—and still shapes modern AI reasoning! #ModalLogic #ScholasticDebate
June 12, 2025 at 3:00 PM
My paper 'Semantical Analysis of Intuitionistic Modal Logics between CK and IK', with Jim de Groot and Ian Shillito, is now in its final edited preprint form: https://arxiv.org/abs/2408.00262 . I will travelling to #lics #lics2025 to present it in Singapore in late June. #logic #ModalLogic
Semantical Analysis of Intuitionistic Modal Logics between CK and IK
The intuitionistic modal logics considered between Constructive K (CK) and Intuitionistic K (IK) differ in their treatment of the possibility (diamond) connective. It was recently rediscovered that some logics between CK and IK also disagree on their diamond-free fragments, with only some remaining conservative over the standard axiomatisation of intuitionistic modal logic with necessity (box) alone. We show that relational Kripke semantics for CK can be extended with frame conditions for all axioms in the standard axiomatisation of IK, as well as other axioms previously studied. This allows us to answer open questions about the (non-)conservativity of such logics over intuitionistic modal logic without diamond. Our results are formalised using the Coq Proof Assistant.
arxiv.org
May 2, 2025 at 5:03 AM
6/10: Ott proposes a fourfold systematics: logical (modal basics), empirical (factual alternatives), epistemic (limited knowledge), and technical (simulations), applied to physics, philosophy, and society. #ModalLogic #Sociology
August 30, 2025 at 11:13 AM
It’s a cloudy and cold Tuesday, and I’m inside writing about refinement.

At least I *think* I understand what I’m doing a bit better than Mark S and his team of macrodata refiners do.

(That’s an inappropriate #Severance, #prooftheory #ModalLogic and […]

[Original post on hcommons.social]
January 7, 2025 at 1:11 PM