Metamath Proof Explorer


Theorem neik0pk1imk0

Description: Kuratowski's K0' and K1 axioms imply K0. Neighborhood version. (Contributed by RP, 3-Jun-2021)

Ref Expression
Hypotheses neik0pk1imk0.bex ( 𝜑𝐵𝑉 )
neik0pk1imk0.n ( 𝜑𝑁 ∈ ( 𝒫 𝒫 𝐵m 𝐵 ) )
neik0pk1imk0.k0p ( 𝜑 → ∀ 𝑥𝐵 ( 𝑁𝑥 ) ≠ ∅ )
neik0pk1imk0.k1 ( 𝜑 → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) )
Assertion neik0pk1imk0 ( 𝜑 → ∀ 𝑥𝐵 𝐵 ∈ ( 𝑁𝑥 ) )

Proof

Step Hyp Ref Expression
1 neik0pk1imk0.bex ( 𝜑𝐵𝑉 )
2 neik0pk1imk0.n ( 𝜑𝑁 ∈ ( 𝒫 𝒫 𝐵m 𝐵 ) )
3 neik0pk1imk0.k0p ( 𝜑 → ∀ 𝑥𝐵 ( 𝑁𝑥 ) ≠ ∅ )
4 neik0pk1imk0.k1 ( 𝜑 → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) )
5 pwidg ( 𝐵𝑉𝐵 ∈ 𝒫 𝐵 )
6 sseq2 ( 𝑡 = 𝐵 → ( 𝑠𝑡𝑠𝐵 ) )
7 6 anbi2d ( 𝑡 = 𝐵 → ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) ↔ ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) ) )
8 eleq1 ( 𝑡 = 𝐵 → ( 𝑡 ∈ ( 𝑁𝑥 ) ↔ 𝐵 ∈ ( 𝑁𝑥 ) ) )
9 7 8 imbi12d ( 𝑡 = 𝐵 → ( ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) ↔ ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
10 9 rspcv ( 𝐵 ∈ 𝒫 𝐵 → ( ∀ 𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) → ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
11 1 5 10 3syl ( 𝜑 → ( ∀ 𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) → ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
12 11 ralimdv ( 𝜑 → ( ∀ 𝑠 ∈ 𝒫 𝐵𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) → ∀ 𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
13 12 ralimdv ( 𝜑 → ( ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵𝑡 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝑡 ) → 𝑡 ∈ ( 𝑁𝑥 ) ) → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
14 4 13 mpd ( 𝜑 → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) )
15 r19.23v ( ∀ 𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ↔ ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) )
16 15 biimpi ( ∀ 𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) → ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) )
17 16 a1i ( 𝜑 → ( ∀ 𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) → ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
18 17 ralimdv ( 𝜑 → ( ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) → ∀ 𝑥𝐵 ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) ) )
19 14 18 mpd ( 𝜑 → ∀ 𝑥𝐵 ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) )
20 elmapi ( 𝑁 ∈ ( 𝒫 𝒫 𝐵m 𝐵 ) → 𝑁 : 𝐵 ⟶ 𝒫 𝒫 𝐵 )
21 2 20 syl ( 𝜑𝑁 : 𝐵 ⟶ 𝒫 𝒫 𝐵 )
22 21 ffvelrnda ( ( 𝜑𝑥𝐵 ) → ( 𝑁𝑥 ) ∈ 𝒫 𝒫 𝐵 )
23 22 elpwid ( ( 𝜑𝑥𝐵 ) → ( 𝑁𝑥 ) ⊆ 𝒫 𝐵 )
24 23 sseld ( ( 𝜑𝑥𝐵 ) → ( 𝑠 ∈ ( 𝑁𝑥 ) → 𝑠 ∈ 𝒫 𝐵 ) )
25 24 ancrd ( ( 𝜑𝑥𝐵 ) → ( 𝑠 ∈ ( 𝑁𝑥 ) → ( 𝑠 ∈ 𝒫 𝐵𝑠 ∈ ( 𝑁𝑥 ) ) ) )
26 25 eximdv ( ( 𝜑𝑥𝐵 ) → ( ∃ 𝑠 𝑠 ∈ ( 𝑁𝑥 ) → ∃ 𝑠 ( 𝑠 ∈ 𝒫 𝐵𝑠 ∈ ( 𝑁𝑥 ) ) ) )
27 n0 ( ( 𝑁𝑥 ) ≠ ∅ ↔ ∃ 𝑠 𝑠 ∈ ( 𝑁𝑥 ) )
28 df-rex ( ∃ 𝑠 ∈ 𝒫 𝐵 𝑠 ∈ ( 𝑁𝑥 ) ↔ ∃ 𝑠 ( 𝑠 ∈ 𝒫 𝐵𝑠 ∈ ( 𝑁𝑥 ) ) )
29 26 27 28 3imtr4g ( ( 𝜑𝑥𝐵 ) → ( ( 𝑁𝑥 ) ≠ ∅ → ∃ 𝑠 ∈ 𝒫 𝐵 𝑠 ∈ ( 𝑁𝑥 ) ) )
30 29 imp ( ( ( 𝜑𝑥𝐵 ) ∧ ( 𝑁𝑥 ) ≠ ∅ ) → ∃ 𝑠 ∈ 𝒫 𝐵 𝑠 ∈ ( 𝑁𝑥 ) )
31 elpwi ( 𝑠 ∈ 𝒫 𝐵𝑠𝐵 )
32 24 31 syl6 ( ( 𝜑𝑥𝐵 ) → ( 𝑠 ∈ ( 𝑁𝑥 ) → 𝑠𝐵 ) )
33 32 ralrimivw ( ( 𝜑𝑥𝐵 ) → ∀ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) → 𝑠𝐵 ) )
34 33 adantr ( ( ( 𝜑𝑥𝐵 ) ∧ ( 𝑁𝑥 ) ≠ ∅ ) → ∀ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) → 𝑠𝐵 ) )
35 30 34 r19.29imd ( ( ( 𝜑𝑥𝐵 ) ∧ ( 𝑁𝑥 ) ≠ ∅ ) → ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) )
36 35 ex ( ( 𝜑𝑥𝐵 ) → ( ( 𝑁𝑥 ) ≠ ∅ → ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) ) )
37 36 ralimdva ( 𝜑 → ( ∀ 𝑥𝐵 ( 𝑁𝑥 ) ≠ ∅ → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) ) )
38 3 37 mpd ( 𝜑 → ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) )
39 ralim ( ∀ 𝑥𝐵 ( ∃ 𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → 𝐵 ∈ ( 𝑁𝑥 ) ) → ( ∀ 𝑥𝐵𝑠 ∈ 𝒫 𝐵 ( 𝑠 ∈ ( 𝑁𝑥 ) ∧ 𝑠𝐵 ) → ∀ 𝑥𝐵 𝐵 ∈ ( 𝑁𝑥 ) ) )
40 19 38 39 sylc ( 𝜑 → ∀ 𝑥𝐵 𝐵 ∈ ( 𝑁𝑥 ) )