Theorem permaxpr 45610

Description: The Axiom of Pairing ax-pr 5405 holds in permutation models. Part of Exercise II.9.2 of [Kunen2] p. 148. (Contributed by Eric Schmidt, 6-Nov-2025.)

Hypotheses

Ref	Expression
permmodel.1	⊢ 𝐹:V–1-1-onto→V
permmodel.2	⊢ 𝑅 = (◡𝐹 ∘ E )

Assertion

Ref	Expression
permaxpr	⊢ ∃𝑧∀𝑤((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅𝑧)

Distinct variable groups:   𝑥,𝑧,𝑤   𝑦,𝑧,𝑤   𝑧,𝐹,𝑤

Allowed substitution hints:   𝑅(𝑥,𝑦,𝑧,𝑤)   𝐹(𝑥,𝑦)

Proof of Theorem permaxpr

Step	Hyp	Ref	Expression
1		fvex 6895	. 2 ⊢ (◡𝐹‘{𝑥, 𝑦}) ∈ V
2		breq2 5117	. . . 4 ⊢ (𝑧 = (◡𝐹‘{𝑥, 𝑦}) → (𝑤𝑅𝑧 ↔ 𝑤𝑅(◡𝐹‘{𝑥, 𝑦})))
3	2	imbi2d 343	. . 3 ⊢ (𝑧 = (◡𝐹‘{𝑥, 𝑦}) → (((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅𝑧) ↔ ((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅(◡𝐹‘{𝑥, 𝑦}))))
4	3	albidv 1947	. 2 ⊢ (𝑧 = (◡𝐹‘{𝑥, 𝑦}) → (∀𝑤((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅𝑧) ↔ ∀𝑤((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅(◡𝐹‘{𝑥, 𝑦}))))
5		permmodel.1	. . . . 5 ⊢ 𝐹:V–1-1-onto→V
6		permmodel.2	. . . . 5 ⊢ 𝑅 = (◡𝐹 ∘ E )
7		vex 3467	. . . . 5 ⊢ 𝑤 ∈ V
8		prex 5410	. . . . 5 ⊢ {𝑥, 𝑦} ∈ V
9	5, 6, 7, 8	brpermmodelcnv 45604	. . . 4 ⊢ (𝑤𝑅(◡𝐹‘{𝑥, 𝑦}) ↔ 𝑤 ∈ {𝑥, 𝑦})
10	7	elpr 4619	. . . 4 ⊢ (𝑤 ∈ {𝑥, 𝑦} ↔ (𝑤 = 𝑥 ∨ 𝑤 = 𝑦))
11	9, 10	sylbbr 239	. . 3 ⊢ ((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅(◡𝐹‘{𝑥, 𝑦}))
12	11	ax-gen 1822	. 2 ⊢ ∀𝑤((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅(◡𝐹‘{𝑥, 𝑦}))
13	1, 4, 12	ceqsexv2d 3512	1 ⊢ ∃𝑧∀𝑤((𝑤 = 𝑥 ∨ 𝑤 = 𝑦) → 𝑤𝑅𝑧)

Syntax hints:   → wi 4   ∨ wo 860  ∀wal 1565   = wceq 1567  ∃wex 1806   ∈ wcel 2149  Vcvv 3463  {cpr 4596   class class class wbr 5113   E cep 5561  ^◡ccnv 5661   ∘ ccom 5666  –1-1-onto→wf1o 6536  ‘cfv 6537

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1822  ax-4 1836  ax-5 1937  ax-6 1994  ax-7 2035  ax-8 2151  ax-9 2159  ax-10 2182  ax-11 2198  ax-12 2219  ax-ext 2741  ax-sep 5261  ax-nul 5271  ax-pr 5405

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1570  df-fal 1580  df-ex 1807  df-nf 1811  df-sb 2098  df-mo 2573  df-eu 2603  df-clab 2748  df-cleq 2761  df-clel 2844  df-ne 2965  df-ral 3086  df-rex 3096  df-rab 3424  df-v 3465  df-dif 3916  df-un 3918  df-in 3920  df-ss 3930  df-nul 4295  df-if 4493  df-sn 4595  df-pr 4597  df-op 4601  df-uni 4877  df-br 5114  df-opab 5178  df-id 5557  df-eprel 5562  df-xp 5668  df-rel 5669  df-cnv 5670  df-co 5671  df-dm 5672  df-rn 5673  df-res 5674  df-ima 5675  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-f1 6542  df-fo 6543  df-f1o 6544  df-fv 6545

This theorem is referenced by: (None)