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Diff — Sequent calculus

Revision #1558 → #2185 · back to history

modifiedSequent calculus33c87c64147a
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Mathlib has no formalization of sequent calculus as a proof system; ModelTheory only covers first-order syntax and semantics, not deduction systems.
status—not_formalized
modifiedHilbert stylebb294320cef0
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No Hilbert-style deduction system is defined in Mathlib.
status—not_formalized
modifiedGentzen stylea9721db0682f
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Gentzen-style sequent proofs are not formalized in Mathlib.
status—not_formalized
modifiedNatural deduction3e9260334cd8
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Mathlib does not formalize natural deduction as an explicit proof system.
status—not_formalized
modifiedSequent calculus line form87c7825df693
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—The multi-conclusion sequent form is not defined in Mathlib.
status—not_formalized
modifiedGentzen's Hauptsatz (cut-elimination)7f7385b069a8
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Cut-elimination / Hauptsatz is not in Mathlib (no hits for 'Hauptsatz' or 'cut elimination').
status—not_formalized
modifiedConsistency of Peano arithmetic11c3bc6e5214
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Gentzen's transfinite consistency proof of PA is not formalized in Mathlib.
status—not_formalized
modifiedHilbert-style judgment463d96cefb79
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Mathlib has no Hilbert-style judgment form.
status—not_formalized
modifiedNatural deduction judgment043d7a433533
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Natural-deduction judgments Γ ⊢ A are not formalized in Mathlib.
status—not_formalized
modifiedSemantics of natural deduction judgmente422b9ae5fd2
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No formalized semantics of natural-deduction judgments in Mathlib.
status—not_formalized
modifiedSequent880766f809f5
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—There is no 'sequent' object defined in Mathlib (the 89 hits for 'sequent' are all 'sequence'/'sequential').
status—not_formalized
modifiedAntecedent and succedentc46201d99a78
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Antecedent/succedent terminology and the underlying sequent object are absent from Mathlib.
status—not_formalized
modifiedSemantics of a sequentf326ad643b9d
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Sequent semantics ⋀Γ ⊨ ⋁Δ is not in Mathlib.
status—not_formalized
modifiedEmpty sequent is false182ffe24f234
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No sequents are defined, so no statement about the empty sequent.
status—not_formalized
modifiedClassical reformulations of sequent semantics958fcb3f047c
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Classical equivalences of sequent semantics are not formalized in Mathlib.
status—not_formalized
modifiedReduction tree example formulaebadc802a543
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Specific reduction-tree example is not in Mathlib.
status—not_formalized
modifiedReduction treec15126b701ab
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Reduction trees for sequents are not defined in Mathlib.
status—not_formalized
modifiedAxiom condition for atomic sequentsfb5dbb2a0ae1
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No formalization of the atomic-axiom criterion.
status—not_formalized
modifiedSoundness and completeness of reduction-tree systemd394873b2142
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Soundness/completeness of a reduction-tree calculus is not formalized in Mathlib.
status—not_formalized
modifiedProvability via reduction trees69e84f8425ac
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No Mathlib statement linking Hilbert provability to reduction trees.
status—not_formalized
modifiedFormal proof in LK619259b91d0e
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—LK proofs are not defined in Mathlib.
status—not_formalized
modifiedFree variable occurrencea494e43e1370
FieldFrom #1558To #2185
mathlib.decl—FirstOrder.Language.BoundedFormula.freeVarFinset
mathlib.match_kind—generalization
mathlib.module—Mathlib.ModelTheory.Syntax
note—Mathlib's ModelTheory tracks free variables in first-order formulas (e.g. freeVarFinset), but not as part of a sequent-calculus inference system.
status—partial
modifiedSubstitution notation27c55c818a61
FieldFrom #1558To #2185
mathlib.decl—FirstOrder.Language.BoundedFormula.subst
mathlib.match_kind—generalization
mathlib.module—Mathlib.ModelTheory.Syntax
note—Substitution of terms into first-order formulas exists in ModelTheory (e.g. BoundedFormula.subst), though not tied to LK notation.
status—partial
modifiedStructural rule abbreviationsb056a39e4302
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Structural inference rules (W/C/P) are not defined in Mathlib.
status—not_formalized
modifiedCut-elimination theorem3364bc35f434
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Cut-elimination is not formalized in Mathlib.
status—not_formalized
modifiedCompleteness of atomic initial sequents6527c3d1878a
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No formalization of restricting LK's initial rule to atomic formulas.
status—not_formalized
modifiedLaw of excluded middle derivation3c7ef824fda4
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—The LEM derivation in LK is not formalized; Mathlib has Classical.em as a logical axiom, not a sequent-calculus derivation.
status—not_formalized
modifiedQuantifier fact derivationc1c55ef887c7
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No LK example derivations are formalized in Mathlib.
status—not_formalized
modifiedLK derivation showing automated proving03d491c3e8ae
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—LK and automated derivation in LK are not formalized in Mathlib.
status—not_formalized
modifiedSequent proof ↔ closed analytic tableau2631950d9ab8
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Mathlib has neither sequent proofs nor analytic tableaux to relate.
status—not_formalized
modifiedWeakening rule95d791b659d1
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No Weakening inference rule is defined in Mathlib.
status—not_formalized
modifiedContraction and Permutation7784176e4039
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Contraction and Permutation structural rules are not formalized in Mathlib.
status—not_formalized
modifiedSubstructural logicsb1f46a3eb93b
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Substructural logics are not defined in Mathlib.
status—not_formalized
modifiedSoundness and completeness of LK99e69bcc3ab2
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—LK soundness and completeness are not formalized in Mathlib (Mathlib has model-theoretic semantics but no LK proof system).
status—not_formalized
modifiedAdmissibility of cut (Hauptsatz)ebe23e05c0f5
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Admissibility of cut in sequent calculus is not formalized in Mathlib.
status—not_formalized
modifiedAdmissibility of weakening via modified axiom5cf79469df2a
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Variants of LK's axiom rule and weakening admissibility are not in Mathlib.
status—not_formalized
modifiedAbsurdity constant8e1c115e7564
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—No object-level absurdity constant with a sequent-calculus axiom is defined in Mathlib (Lean's False is metalevel).
status—not_formalized
modifiedNegation from implication3ac30411bf39
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Definition of ¬A := A → ⊥ inside a formal proof system is not given in Mathlib.
status—not_formalized
modifiedSystem LJe04ee6ab443b
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—The intuitionistic sequent calculus LJ is not defined in Mathlib.
status—not_formalized
modifiedSoundness and completeness of LJadea44d23db0
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—LJ soundness/completeness and its cut-elimination are absent from Mathlib.
status—not_formalized
modifiedDisjunction and existence properties9ad7e290763b
FieldFrom #1558To #2185
mathlib.decl——
mathlib.match_kind——
mathlib.module——
note—Intuitionistic disjunction/existence properties for LJ are not formalized in Mathlib.
status—not_formalized
addedSequent (Gentzen's terminology)65773e5bb160
addedCedents (sequent formulas)4aab0313c9dc
addedLeft–right symmetry from De Morgan duality1922335d590d
addedConjunction/disjunction reading of cedentsc3f434bd42a5
addedEigenvariable restriction on quantifier rulesdca83fdf242a
addedContexts (Γ, Δ)b24afc2e5c61
addedRestriction to single-formula succedents for LJeb24bc8ab1e8
addedModus ponens implemented by cuta28d91aa6cd6