Step | Hyp | Ref
| Expression |
1 | | frd.3 |
. 2
⊢ (φ → X ⊆ A) |
2 | | frd.4 |
. 2
⊢ (φ → X ≠ ∅) |
3 | | frd.2 |
. . 3
⊢ (φ → X ∈ V) |
4 | | frd.1 |
. . . 4
⊢ (φ → R Fr A) |
5 | | brex 4690 |
. . . . . 6
⊢ (R Fr A → (R
∈ V ∧
A ∈
V)) |
6 | | breq 4642 |
. . . . . . . . . . 11
⊢ (r = R →
(zry ↔
zRy)) |
7 | 6 | imbi1d 308 |
. . . . . . . . . 10
⊢ (r = R →
((zry →
z = y)
↔ (zRy →
z = y))) |
8 | 7 | rexralbidv 2659 |
. . . . . . . . 9
⊢ (r = R →
(∃y
∈ x ∀z ∈ x (zry → z =
y) ↔ ∃y ∈ x ∀z ∈ x (zRy → z =
y))) |
9 | 8 | imbi2d 307 |
. . . . . . . 8
⊢ (r = R →
(((x ⊆
a ∧
x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zry → z =
y)) ↔ ((x ⊆ a ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
10 | 9 | albidv 1625 |
. . . . . . 7
⊢ (r = R →
(∀x((x ⊆ a ∧ x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zry → z =
y)) ↔ ∀x((x ⊆ a ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
11 | | sseq2 3294 |
. . . . . . . . . 10
⊢ (a = A →
(x ⊆
a ↔ x ⊆ A)) |
12 | 11 | anbi1d 685 |
. . . . . . . . 9
⊢ (a = A →
((x ⊆
a ∧
x ≠ ∅) ↔ (x
⊆ A
∧ x ≠
∅))) |
13 | 12 | imbi1d 308 |
. . . . . . . 8
⊢ (a = A →
(((x ⊆
a ∧
x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zRy → z =
y)) ↔ ((x ⊆ A ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
14 | 13 | albidv 1625 |
. . . . . . 7
⊢ (a = A →
(∀x((x ⊆ a ∧ x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zRy → z =
y)) ↔ ∀x((x ⊆ A ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
15 | | df-found 5906 |
. . . . . . 7
⊢ Fr = {〈r, a〉 ∣ ∀x((x ⊆ a ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zry → z =
y))} |
16 | 10, 14, 15 | brabg 4707 |
. . . . . 6
⊢ ((R ∈ V ∧ A ∈ V) → (R
Fr A ↔
∀x((x ⊆ A ∧ x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
17 | 5, 16 | syl 15 |
. . . . 5
⊢ (R Fr A → (R
Fr A ↔
∀x((x ⊆ A ∧ x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zRy → z =
y)))) |
18 | 17 | ibi 232 |
. . . 4
⊢ (R Fr A → ∀x((x ⊆ A ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y))) |
19 | 4, 18 | syl 15 |
. . 3
⊢ (φ → ∀x((x ⊆ A ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y))) |
20 | | sseq1 3293 |
. . . . . 6
⊢ (x = X →
(x ⊆
A ↔ X ⊆ A)) |
21 | | neeq1 2525 |
. . . . . 6
⊢ (x = X →
(x ≠ ∅ ↔ X
≠ ∅)) |
22 | 20, 21 | anbi12d 691 |
. . . . 5
⊢ (x = X →
((x ⊆
A ∧
x ≠ ∅) ↔ (X
⊆ A
∧ X ≠
∅))) |
23 | | raleq 2808 |
. . . . . 6
⊢ (x = X →
(∀z
∈ x
(zRy →
z = y)
↔ ∀z ∈ X (zRy →
z = y))) |
24 | 23 | rexeqbi1dv 2817 |
. . . . 5
⊢ (x = X →
(∃y
∈ x ∀z ∈ x (zRy → z =
y) ↔ ∃y ∈ X ∀z ∈ X (zRy → z =
y))) |
25 | 22, 24 | imbi12d 311 |
. . . 4
⊢ (x = X →
(((x ⊆
A ∧
x ≠ ∅) → ∃y ∈ x ∀z ∈ x (zRy → z =
y)) ↔ ((X ⊆ A ∧ X ≠ ∅) →
∃y ∈ X ∀z ∈ X (zRy → z =
y)))) |
26 | 25 | spcgv 2940 |
. . 3
⊢ (X ∈ V → (∀x((x ⊆ A ∧ x ≠ ∅) →
∃y ∈ x ∀z ∈ x (zRy → z =
y)) → ((X ⊆ A ∧ X ≠ ∅) →
∃y ∈ X ∀z ∈ X (zRy → z =
y)))) |
27 | 3, 19, 26 | sylc 56 |
. 2
⊢ (φ → ((X ⊆ A ∧ X ≠ ∅) →
∃y ∈ X ∀z ∈ X (zRy → z =
y))) |
28 | 1, 2, 27 | mp2and 660 |
1
⊢ (φ → ∃y ∈ X ∀z ∈ X (zRy → z =
y)) |