Metamath Proof Explorer


Theorem 2reuimp

Description: Implication of a double restricted existential uniqueness in terms of restricted existential quantification and restricted universal quantification if the class of the quantified elements is not empty. (Contributed by AV, 13-Mar-2023)

Ref Expression
Hypotheses 2reuimp.c b = c φ θ
2reuimp.d a = d φ χ
2reuimp.a a = d θ τ
2reuimp.e b = e φ η
2reuimp.f c = f θ ψ
Assertion 2reuimp V ∃! a V ∃! b V φ a V d V b V e V f V c V χ τ b = c ψ η a = d e = f

Proof

Step Hyp Ref Expression
1 2reuimp.c b = c φ θ
2 2reuimp.d a = d φ χ
3 2reuimp.a a = d θ τ
4 2reuimp.e b = e φ η
5 2reuimp.f c = f θ ψ
6 r19.28zv V c V χ τ b = c χ c V τ b = c
7 6 bicomd V χ c V τ b = c c V χ τ b = c
8 7 imbi1d V χ c V τ b = c a = d c V χ τ b = c a = d
9 r19.36zv V c V χ τ b = c a = d c V χ τ b = c a = d
10 r19.42v c V η ψ e = f χ τ b = c a = d η ψ e = f c V χ τ b = c a = d
11 pm5.31r η ψ e = f ψ η e = f
12 pm5.31r ψ η e = f χ τ b = c a = d χ τ b = c ψ η e = f a = d
13 pm5.31r a = d ψ η e = f ψ a = d η e = f
14 an12 a = d η e = f η a = d e = f
15 13 14 syl6ib a = d ψ η e = f ψ η a = d e = f
16 15 ancoms ψ η e = f a = d ψ η a = d e = f
17 12 16 syl6 ψ η e = f χ τ b = c a = d χ τ b = c ψ η a = d e = f
18 11 17 sylan η ψ e = f χ τ b = c a = d χ τ b = c ψ η a = d e = f
19 18 reximi c V η ψ e = f χ τ b = c a = d c V χ τ b = c ψ η a = d e = f
20 10 19 sylbir η ψ e = f c V χ τ b = c a = d c V χ τ b = c ψ η a = d e = f
21 20 expcom c V χ τ b = c a = d η ψ e = f c V χ τ b = c ψ η a = d e = f
22 21 expd c V χ τ b = c a = d η ψ e = f c V χ τ b = c ψ η a = d e = f
23 9 22 syl6bir V c V χ τ b = c a = d η ψ e = f c V χ τ b = c ψ η a = d e = f
24 8 23 sylbid V χ c V τ b = c a = d η ψ e = f c V χ τ b = c ψ η a = d e = f
25 24 com23 V η χ c V τ b = c a = d ψ e = f c V χ τ b = c ψ η a = d e = f
26 25 imp4c V η χ c V τ b = c a = d ψ e = f c V χ τ b = c ψ η a = d e = f
27 26 ralimdv V f V η χ c V τ b = c a = d ψ e = f f V c V χ τ b = c ψ η a = d e = f
28 27 reximdv V e V f V η χ c V τ b = c a = d ψ e = f e V f V c V χ τ b = c ψ η a = d e = f
29 28 ralimdv V b V e V f V η χ c V τ b = c a = d ψ e = f b V e V f V c V χ τ b = c ψ η a = d e = f
30 29 ralimdv V d V b V e V f V η χ c V τ b = c a = d ψ e = f d V b V e V f V c V χ τ b = c ψ η a = d e = f
31 30 reximdv V a V d V b V e V f V η χ c V τ b = c a = d ψ e = f a V d V b V e V f V c V χ τ b = c ψ η a = d e = f
32 1 2 3 4 5 2reuimp0 ∃! a V ∃! b V φ a V d V b V e V f V η χ c V τ b = c a = d ψ e = f
33 31 32 impel V ∃! a V ∃! b V φ a V d V b V e V f V c V χ τ b = c ψ η a = d e = f