NF weak partition development: NFStandard.CylinderToNF.
This module is the presentation-independent end of the Hailperin compiler.
Once a structure supplies the small CylinderAlgebra interface, the generic
compiler constructs the extension of every stratified formula. The lemmas
below turn those constructed extensions back into the closed first-order
sentences comprising NF.
theorem
NFChoice.Foundation.NFStandard.realize_comprehensionInstance_of_cylinder
{S : Fol.Structure LNF}
(C : CylinderAlgebra S)
{n : ℕ}
(p : Formula (n + 1))
(hp : p.Stratified)
:
A cylinder algebra realizes each closed stratified-comprehension axiom.
theorem
NFChoice.Foundation.NFStandard.models_NF_of_cylinder
{S : Fol.Structure LNF}
(C : CylinderAlgebra S)
(hExt : Fol.realizeSentence S (ExactLiteralTrial.literalAxiomFormula HailperinAxiomName.axExt))
:
Extensionality plus a cylinder algebra is a model of standard NF.
No feature of the particular Metamath Hailperin-derived finite presentation is used here.