Cubical Type Theoretic Navya-Ny\=aya
Pith reviewed 2026-05-14 21:44 UTC · model grok-4.3
The pith
Cubical type theory encodes Navya-Nyaya's core structures without losing dependent delimitation or non-extensional identity.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
We give CTT encodings for seven core constructs (sambandha, avacchedaka, abhava, vyapti, tadatmya, higher relations, paryapti) plus the qualifier-qualificand structure. We develop a stratified-universe foundation for the padartha system and prove four signature theorems internal to the encoding (involution of abhava, kevalanvayi irreducibility, coextension without identity, no h-set collapse) together with six metatheoretic results including soundness, conservativity, and faithfulness.
What carries the argument
The CTT encoding of the qualifier-qualificand structure and abhava, which uses De Morgan cubical operations to model dependent delimitation and relations at arbitrary depth.
Load-bearing premise
The load-bearing structures of Navya-Nyaya can be faithfully captured by the native features of cubical type theory without introducing new postulates that alter the original meaning.
What would settle it
A counterexample would be a core Navya-Nyaya construct or Tattvacintamani passage that cannot be encoded without additional postulates or that violates one of the four signature theorems when interpreted inside the cubical encoding.
read the original abstract
We present a formalization of the technical language of Navya-Nyaya - the "New Logic" school of late-classical Indian philosophy - in CCHM De Morgan cubical type theory (CTT). Previous formalization attempts in first-order logic (Matilal), higher-order logic (Ganeri), and Martin-Lof type theory (Bhattacharyya) each lose load-bearing structure: dependent delimitation (avacchedaka), typed absence (abhava), non-extensional identity (tadatmya), or unbounded relational depth (parampara-sambandha). We argue that CTT closes this gap natively. We give CTT encodings for seven core constructs (sambandha, avacchedaka, abhava, vyapti, tadatmya, higher relations, paryapti) plus the qualifier-qualificand structure; develop a stratified-universe foundation for the padartha system; and prove four signature theorems internal to the encoding (involution of abhava, kevalanvayi irreducibility, coextension without identity, no h-set collapse) and six metatheoretic results (soundness, conservativity, faithfulness, distinction preservation, decidability, commentarial conservativity). We close with worked encodings of fifteen Tattvacintamani passages, comparison with prior formalizations, an implementation sketch in Cubical Agda, and five distinguishing predictions - including a novel argument from Navya-Nyaya's involutive-negation doctrine for the necessity of De Morgan over Cartesian cubical foundations.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper presents a formalization of the technical language of Navya-Nyaya in CCHM De Morgan cubical type theory (CTT). It provides CTT encodings for seven core constructs including sambandha, avacchedaka, abhava, vyapti, tadatmya, higher relations, and paryapti, along with the qualifier-qualificand structure. A stratified-universe foundation for the padartha system is developed. Four signature theorems are proved internally to the encoding: involution of abhava, kevalanvayi irreducibility, coextension without identity, and no h-set collapse. Six metatheoretic results are established: soundness, conservativity, faithfulness, distinction preservation, decidability, and commentarial conservativity. The manuscript includes worked encodings of fifteen passages from the Tattvacintamani, a comparison with prior formalizations, an implementation sketch in Cubical Agda, and five distinguishing predictions.
Significance. If the encodings faithfully capture the load-bearing structures of Navya-Nyaya without introducing altering postulates, this work represents a significant advance in applying modern type theory to classical Indian philosophy. The use of native CTT features for dependent delimitation and non-extensional identity addresses gaps in previous formalizations in FOL, HOL, and MLTT. The internal proofs of the signature theorems and metatheoretic properties lend credibility to the claims. The inclusion of concrete encodings, implementation sketch, and testable predictions strengthens the contribution and provides a basis for further research in both fields.
minor comments (3)
- [Abstract] The abstract lists six metatheoretic results (soundness, conservativity, etc.) without brief definitions or examples; a short parenthetical gloss in the abstract or introduction would aid accessibility for readers outside type theory.
- [Implementation sketch] The implementation sketch in Cubical Agda is mentioned but lacks even one short code fragment (e.g., the encoding of abhava as an involutive negation); adding a minimal illustrative snippet would make the claim of native capture more concrete.
- Ensure the bibliography contains complete entries for the cited prior formalizations (Matilal, Ganeri, Bhattacharyya) and any CTT references used in the metatheoretic arguments.
Simulated Author's Rebuttal
We thank the referee for the careful and positive evaluation of our manuscript. The recognition of the contribution in applying CTT to Navya-Nyāya, the assessment of the encodings and metatheoretic results, and the recommendation for minor revision are appreciated. No specific major comments were provided in the report.
Circularity Check
No significant circularity; derivations are self-contained in native CTT
full rationale
The paper encodes seven Navya-Nyaya constructs directly in CCHM De Morgan cubical type theory and proves its four signature theorems (involution of abhava, kevalanvayi irreducibility, coextension without identity, no h-set collapse) plus six metatheoretic results internally from the native path, interval, and De Morgan structure. No parameter is fitted to data and then relabeled a prediction; no self-citation chain is invoked to justify the central encoding or to forbid alternatives; the qualifier-qualificand structure and stratified universes are introduced explicitly rather than smuggled via prior work by the same authors. The five distinguishing predictions are derived consequences of the involutive-negation encoding rather than inputs renamed as outputs. The argument therefore reduces to standard CTT axioms plus the explicit translation, with no definitional collapse or load-bearing self-reference.
Axiom & Free-Parameter Ledger
axioms (1)
- standard math Axioms and rules of CCHM De Morgan cubical type theory
Reference graph
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discussion (0)
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