Metamath Proof Explorer


Theorem wevsev

Description: If R is a well-ordering of the universe, then S is a set-like well-ordering of the universe. This is the ZFC version of (3 -> 4) in https://tinyurl.com/hamkins-gblac . (Contributed by BTernaryTau, 18-Sep-2026)

Ref Expression
Hypothesis wevsev.1 ⊢ 𝑆 = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( rank ‘ 𝑥 ) ∈ ( rank ‘ 𝑦 ) ∨ ( ( rank ‘ 𝑥 ) = ( rank ‘ 𝑦 ) ∧ 𝑥 𝑅 𝑦 ) ) }
Assertion wevsev ( 𝑅 We V → ( 𝑆 We V ∧ 𝑆 Se V ) )

Proof

Step Hyp Ref Expression
1 wevsev.1 ⊢ 𝑆 = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( rank ‘ 𝑥 ) ∈ ( rank ‘ 𝑦 ) ∨ ( ( rank ‘ 𝑥 ) = ( rank ‘ 𝑦 ) ∧ 𝑥 𝑅 𝑦 ) ) }
2 ssv ⊢ { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } ⊆ V
3 wess ⊢ ( { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } ⊆ V → ( 𝑅 We V → 𝑅 We { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } ) )
4 2 3 ax-mp ⊢ ( 𝑅 We V → 𝑅 We { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } )
5 4 ralrimivw ⊢ ( 𝑅 We V → ∀ 𝑤 ∈ V 𝑅 We { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } )
6 1 werankwe2 ⊢ ( ∀ 𝑤 ∈ V 𝑅 We { 𝑧 ∈ V ∣ ( rank ‘ 𝑧 ) = ( rank ‘ 𝑤 ) } → 𝑆 We V )
7 5 6 syl ⊢ ( 𝑅 We V → 𝑆 We V )
8 1 rankse ⊢ 𝑆 Se V
9 7 8 jctir ⊢ ( 𝑅 We V → ( 𝑆 We V ∧ 𝑆 Se V ) )