Metamath Proof Explorer


Theorem eltsk2g

Description: Properties of a Tarski class. (Contributed by FL, 30-Dec-2010) (Revised by Mario Carneiro, 20-Sep-2014)

Ref Expression
Assertion eltsk2g ( 𝑇𝑉 → ( 𝑇 ∈ Tarski ↔ ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) ∧ ∀ 𝑧 ∈ 𝒫 𝑇 ( 𝑧𝑇𝑧𝑇 ) ) ) )

Proof

Step Hyp Ref Expression
1 eltskg ( 𝑇𝑉 → ( 𝑇 ∈ Tarski ↔ ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) ∧ ∀ 𝑧 ∈ 𝒫 𝑇 ( 𝑧𝑇𝑧𝑇 ) ) ) )
2 nfra1 𝑧𝑧𝑇 𝒫 𝑧𝑇
3 pweq ( 𝑧 = 𝑤 → 𝒫 𝑧 = 𝒫 𝑤 )
4 3 sseq1d ( 𝑧 = 𝑤 → ( 𝒫 𝑧𝑇 ↔ 𝒫 𝑤𝑇 ) )
5 4 rspccva ( ( ∀ 𝑧𝑇 𝒫 𝑧𝑇𝑤𝑇 ) → 𝒫 𝑤𝑇 )
6 5 adantlr ( ( ( ∀ 𝑧𝑇 𝒫 𝑧𝑇𝑧𝑇 ) ∧ 𝑤𝑇 ) → 𝒫 𝑤𝑇 )
7 vpwex 𝒫 𝑧 ∈ V
8 7 elpw ( 𝒫 𝑧 ∈ 𝒫 𝑤 ↔ 𝒫 𝑧𝑤 )
9 ssel ( 𝒫 𝑤𝑇 → ( 𝒫 𝑧 ∈ 𝒫 𝑤 → 𝒫 𝑧𝑇 ) )
10 8 9 syl5bir ( 𝒫 𝑤𝑇 → ( 𝒫 𝑧𝑤 → 𝒫 𝑧𝑇 ) )
11 6 10 syl ( ( ( ∀ 𝑧𝑇 𝒫 𝑧𝑇𝑧𝑇 ) ∧ 𝑤𝑇 ) → ( 𝒫 𝑧𝑤 → 𝒫 𝑧𝑇 ) )
12 11 rexlimdva ( ( ∀ 𝑧𝑇 𝒫 𝑧𝑇𝑧𝑇 ) → ( ∃ 𝑤𝑇 𝒫 𝑧𝑤 → 𝒫 𝑧𝑇 ) )
13 2 12 ralimdaa ( ∀ 𝑧𝑇 𝒫 𝑧𝑇 → ( ∀ 𝑧𝑇𝑤𝑇 𝒫 𝑧𝑤 → ∀ 𝑧𝑇 𝒫 𝑧𝑇 ) )
14 13 imdistani ( ( ∀ 𝑧𝑇 𝒫 𝑧𝑇 ∧ ∀ 𝑧𝑇𝑤𝑇 𝒫 𝑧𝑤 ) → ( ∀ 𝑧𝑇 𝒫 𝑧𝑇 ∧ ∀ 𝑧𝑇 𝒫 𝑧𝑇 ) )
15 r19.26 ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) ↔ ( ∀ 𝑧𝑇 𝒫 𝑧𝑇 ∧ ∀ 𝑧𝑇𝑤𝑇 𝒫 𝑧𝑤 ) )
16 r19.26 ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) ↔ ( ∀ 𝑧𝑇 𝒫 𝑧𝑇 ∧ ∀ 𝑧𝑇 𝒫 𝑧𝑇 ) )
17 14 15 16 3imtr4i ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) → ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) )
18 ssid 𝒫 𝑧 ⊆ 𝒫 𝑧
19 sseq2 ( 𝑤 = 𝒫 𝑧 → ( 𝒫 𝑧𝑤 ↔ 𝒫 𝑧 ⊆ 𝒫 𝑧 ) )
20 19 rspcev ( ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧 ⊆ 𝒫 𝑧 ) → ∃ 𝑤𝑇 𝒫 𝑧𝑤 )
21 18 20 mpan2 ( 𝒫 𝑧𝑇 → ∃ 𝑤𝑇 𝒫 𝑧𝑤 )
22 21 anim2i ( ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) → ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) )
23 22 ralimi ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) → ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) )
24 17 23 impbii ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) ↔ ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) )
25 24 anbi1i ( ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ ∃ 𝑤𝑇 𝒫 𝑧𝑤 ) ∧ ∀ 𝑧 ∈ 𝒫 𝑇 ( 𝑧𝑇𝑧𝑇 ) ) ↔ ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) ∧ ∀ 𝑧 ∈ 𝒫 𝑇 ( 𝑧𝑇𝑧𝑇 ) ) )
26 1 25 bitrdi ( 𝑇𝑉 → ( 𝑇 ∈ Tarski ↔ ( ∀ 𝑧𝑇 ( 𝒫 𝑧𝑇 ∧ 𝒫 𝑧𝑇 ) ∧ ∀ 𝑧 ∈ 𝒫 𝑇 ( 𝑧𝑇𝑧𝑇 ) ) ) )