Metamath Proof Explorer


Theorem wuncss

Description: The weak universe closure is a subset of any other weak universe containing the set. (Contributed by Mario Carneiro, 2-Jan-2017)

Ref Expression
Assertion wuncss ( ( 𝑈 ∈ WUni ∧ 𝐴 ⊆ 𝑈 ) → ( wUniCl ‘ 𝐴 ) ⊆ 𝑈 )

Proof

Step Hyp Ref Expression
1 ssexg ⊢ ( ( 𝐴 ⊆ 𝑈 ∧ 𝑈 ∈ WUni ) → 𝐴 ∈ V )
2 1 ancoms ⊢ ( ( 𝑈 ∈ WUni ∧ 𝐴 ⊆ 𝑈 ) → 𝐴 ∈ V )
3 wuncval ⊢ ( 𝐴 ∈ V → ( wUniCl ‘ 𝐴 ) = ∩ { 𝑢 ∈ WUni ∣ 𝐴 ⊆ 𝑢 } )
4 2 3 syl ⊢ ( ( 𝑈 ∈ WUni ∧ 𝐴 ⊆ 𝑈 ) → ( wUniCl ‘ 𝐴 ) = ∩ { 𝑢 ∈ WUni ∣ 𝐴 ⊆ 𝑢 } )
5 sseq2 ⊢ ( 𝑢 = 𝑈 → ( 𝐴 ⊆ 𝑢 ↔ 𝐴 ⊆ 𝑈 ) )
6 5 intminss ⊢ ( ( 𝑈 ∈ WUni ∧ 𝐴 ⊆ 𝑈 ) → ∩ { 𝑢 ∈ WUni ∣ 𝐴 ⊆ 𝑢 } ⊆ 𝑈 )
7 4 6 eqsstrd ⊢ ( ( 𝑈 ∈ WUni ∧ 𝐴 ⊆ 𝑈 ) → ( wUniCl ‘ 𝐴 ) ⊆ 𝑈 )