Metamath Proof Explorer


Theorem rr-grothshortbi

Description: Express "every set is contained in a Grothendieck universe" in a short form while avoiding complicated definitions. (Contributed by Rohan Ridenour, 8-Oct-2024)

Ref Expression
Assertion rr-grothshortbi ( ∀ 𝑥 ∃ 𝑦 ∈ Univ 𝑥 ∈ 𝑦 ↔ ∀ 𝑥 ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) ) )

Proof

Step Hyp Ref Expression
1 df-rex ⊢ ( ∃ 𝑦 ∈ Univ 𝑥 ∈ 𝑦 ↔ ∃ 𝑦 ( 𝑦 ∈ Univ ∧ 𝑥 ∈ 𝑦 ) )
2 exancom ⊢ ( ∃ 𝑦 ( 𝑦 ∈ Univ ∧ 𝑥 ∈ 𝑦 ) ↔ ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ 𝑦 ∈ Univ ) )
3 dfuniv2 ⊢ Univ = { 𝑦 ∣ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) }
4 3 eqabri ⊢ ( 𝑦 ∈ Univ ↔ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) )
5 4 anbi2i ⊢ ( ( 𝑥 ∈ 𝑦 ∧ 𝑦 ∈ Univ ) ↔ ( 𝑥 ∈ 𝑦 ∧ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) ) )
6 5 exbii ⊢ ( ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ 𝑦 ∈ Univ ) ↔ ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) ) )
7 1 2 6 3bitri ⊢ ( ∃ 𝑦 ∈ Univ 𝑥 ∈ 𝑦 ↔ ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) ) )
8 7 albii ⊢ ( ∀ 𝑥 ∃ 𝑦 ∈ Univ 𝑥 ∈ 𝑦 ↔ ∀ 𝑥 ∃ 𝑦 ( 𝑥 ∈ 𝑦 ∧ ∀ 𝑧 ∈ 𝑦 ∀ 𝑓 ∈ 𝒫 𝑦 ∃ 𝑤 ∈ 𝑦 ( 𝒫 𝑧 ⊆ ( 𝑦 ∩ 𝑤 ) ∧ ( 𝑧 ∩ ∪ 𝑓 ) ⊆ ∪ ( 𝑓 ∩ 𝒫 𝒫 𝑤 ) ) ) )