Proof of Theorem intab
| Step | Hyp | Ref
| Expression |
| 1 | | eqeq1 1479 |
. . . . . . . . . . 11
⊢ (z =
x → (z = A ↔
x = A)) |
| 2 | 1 | anbi2d 615 |
. . . . . . . . . 10
⊢ (z =
x → ((φ ⋀ z = A) ↔
(φ ⋀ x = A))) |
| 3 | 2 | exbidv 1278 |
. . . . . . . . 9
⊢ (z =
x → (∃y(φ ⋀
z = A)
↔ ∃y(φ ⋀ x = A))) |
| 4 | 3 | cbvabv 1906 |
. . . . . . . 8
⊢ {z∣∃y(φ ⋀
z = A)}
= {x∣∃y(φ ⋀
x = A)} |
| 5 | | intab.2 |
. . . . . . . 8
⊢ {x∣∃y(φ ⋀
x = A)}
∈ V |
| 6 | 4, 5 | eqeltr 1542 |
. . . . . . 7
⊢ {z∣∃y(φ ⋀
z = A)}
∈ V |
| 7 | | hbe1 1015 |
. . . . . . . . . 10
⊢ (∃y(φ ⋀
z = A)
→ ∀y∃y(φ ⋀
z = A)) |
| 8 | 7 | hbab 1466 |
. . . . . . . . 9
⊢ (x
∈ {z∣∃y(φ ⋀
z = A)}
→ ∀y x ∈ {z∣∃y(φ ⋀
z = A)}) |
| 9 | 8 | hbeleq 1565 |
. . . . . . . 8
⊢ (x =
{z∣∃y(φ ⋀
z = A)}
→ ∀y x = {z∣∃y(φ ⋀
z = A)}) |
| 10 | | eleq2 1533 |
. . . . . . . . 9
⊢ (x =
{z∣∃y(φ ⋀
z = A)}
→ (A ∈ x ↔ A
∈ {z∣∃y(φ ⋀
z = A)})) |
| 11 | 10 | imbi2d 611 |
. . . . . . . 8
⊢ (x =
{z∣∃y(φ ⋀
z = A)}
→ ((φ → A ∈ x)
↔ (φ → A ∈ {z∣∃y(φ ⋀
z = A)}))) |
| 12 | 9, 11 | albid 1103 |
. . . . . . 7
⊢ (x =
{z∣∃y(φ ⋀
z = A)}
→ (∀y(φ → A ∈ x)
↔ ∀y(φ → A ∈ {z∣∃y(φ ⋀
z = A)}))) |
| 13 | 6, 12 | sbcie 1959 |
. . . . . 6
⊢ ([{z∣∃y(φ ⋀
z = A)}
/ x]∀y(φ →
A ∈ x) ↔ ∀y(φ →
A ∈ {z∣∃y(φ ⋀
z = A)})) |
| 14 | | intab.1 |
. . . . . . . . . . . 12
⊢ A
∈ V |
| 15 | | ax-17 970 |
. . . . . . . . . . . . 13
⊢ (φ
→ ∀zφ) |
| 16 | 15 | sbcgf 1983 |
. . . . . . . . . . . 12
⊢ (A
∈ V → ([A / z]φ ↔
φ)) |
| 17 | 14, 16 | ax-mp 7 |
. . . . . . . . . . 11
⊢ ([A /
z]φ
↔ φ) |
| 18 | 17 | biimpr 152 |
. . . . . . . . . 10
⊢ (φ
→ [A / z]φ) |
| 19 | | csbvarg 2018 |
. . . . . . . . . . . 12
⊢ (A
∈ V → [A / z]z =
A) |
| 20 | 14, 19 | ax-mp 7 |
. . . . . . . . . . 11
⊢ [A / z]z =
A |
| 21 | | sbceq1dig 2011 |
. . . . . . . . . . . 12
⊢ (A
∈ V → ([A / z]z = A ↔ [A / z]z =
A)) |
| 22 | 14, 21 | ax-mp 7 |
. . . . . . . . . . 11
⊢ ([A /
z]z =
A ↔ [A / z]z =
A) |
| 23 | 20, 22 | mpbir 190 |
. . . . . . . . . 10
⊢ [A /
z]z =
A |
| 24 | 18, 23 | jctir 293 |
. . . . . . . . 9
⊢ (φ
→ ([A / z]φ ⋀
[A / z]z = A)) |
| 25 | | sbcang 1968 |
. . . . . . . . . 10
⊢ (A
∈ V → ([A / z](φ ⋀
z = A)
↔ ([A / z]φ ⋀
[A / z]z = A))) |
| 26 | 14, 25 | ax-mp 7 |
. . . . . . . . 9
⊢ ([A /
z](φ ⋀ z = A) ↔
([A / z]φ ⋀
[A / z]z = A)) |
| 27 | 24, 26 | sylibr 200 |
. . . . . . . 8
⊢ (φ
→ [A / z](φ ⋀
z = A)) |
| 28 | | 19.8a 1028 |
. . . . . . . . . . 11
⊢ ((φ ⋀ z = A) →
∃y(φ ⋀ z = A)) |
| 29 | 28 | ax-gen 962 |
. . . . . . . . . 10
⊢ ∀z((φ ⋀
z = A)
→ ∃y(φ ⋀ z = A)) |
| 30 | | a4sbc 1942 |
. . . . . . . . . 10
⊢ (A
∈ V → (∀z((φ ⋀ z = A) →
∃y(φ ⋀ z = A)) →
[A / z]((φ
⋀ z = A) → ∃y(φ ⋀
z = A)))) |
| 31 | 14, 29, 30 | mp2 43 |
. . . . . . . . 9
⊢ [A /
z]((φ ⋀ z = A) →
∃y(φ ⋀ z = A)) |
| 32 | | sbcimg 1967 |
. . . . . . . . . 10
⊢ (A
∈ V → ([A / z]((φ
⋀ z = A) → ∃y(φ ⋀
z = A))
↔ ([A / z](φ ⋀
z = A)
→ [A / z]∃y(φ ⋀ z = A)))) |
| 33 | 14, 32 | ax-mp 7 |
. . . . . . . . 9
⊢ ([A /
z]((φ ⋀ z = A) →
∃y(φ ⋀ z = A)) ↔
([A / z](φ ⋀
z = A)
→ [A / z]∃y(φ ⋀ z = A))) |
| 34 | 31, 33 | mpbi 189 |
. . . . . . . 8
⊢ ([A /
z](φ ⋀ z = A) →
[A / z]∃y(φ ⋀ z = A)) |
| 35 | 27, 34 | syl 10 |
. . . . . . 7
⊢ (φ
→ [A / z]∃y(φ ⋀ z = A)) |
| 36 | 14 | elabs 1963 |
. . . . . . 7
⊢ (A
∈ {z∣∃y(φ ⋀
z = A)}
↔ [A / z]∃y(φ ⋀ z = A)) |
| 37 | 35, 36 | sylibr 200 |
. . . . . 6
⊢ (φ
→ A ∈ {z∣∃y(φ ⋀
z = A)}) |
| 38 | 13, 37 | mpgbir 987 |
. . . . 5
⊢ [{z∣∃y(φ ⋀
z = A)}
/ x]∀y(φ →
A ∈ x) |
| 39 | 6 | elabs 1963 |
. . . . 5
⊢ ({z∣∃y(φ ⋀
z = A)}
∈ {x∣∀y(φ →
A ∈ x)} ↔ [{z∣∃y(φ ⋀
z = A)}
/ x]∀y(φ →
A ∈ x)) |
| 40 | 38, 39 | mpbir 190 |
. . . 4
⊢ {z∣∃y(φ ⋀
z = A)}
∈ {x∣∀y(φ →
A ∈ x)} |
| 41 | | intss1 2544 |
. . . 4
⊢ ({z∣∃y(φ ⋀
z = A)}
∈ {x∣∀y(φ →
A ∈ x)} → ∩{x∣∀y(φ →
A ∈ x)} ⊆ {z∣∃y(φ ⋀
z = A)}) |
| 42 | 40, 41 | ax-mp 7 |
. . 3
⊢ ∩{x∣∀y(φ →
A ∈ x)} ⊆ {z∣∃y(φ ⋀
z = A)} |
| 43 | | hba1 1002 |
. . . . . . 7
⊢ (∀y(φ →
A ∈ x) → ∀y∀y(φ → A ∈ x)) |
| 44 | 43 | hbab 1466 |
. . . . . 6
⊢ (z
∈ {x∣∀y(φ →
A ∈ x)} → ∀y z ∈
{x∣∀y(φ →
A ∈ x)}) |
| 45 | 44 | hbint 2539 |
. . . . 5
⊢ (z
∈ ∩{x∣∀y(φ →
A ∈ x)} → ∀y z ∈ ∩{x∣∀y(φ →
A ∈ x)}) |
| 46 | | ax-4 972 |
. . . . . . . . . 10
⊢ (∀y(φ →
A ∈ x) → (φ
→ A ∈ x)) |
| 47 | 46 | com12 11 |
. . . . . . . . 9
⊢ (φ
→ (∀y(φ → A ∈ x)
→ A ∈ x)) |
| 48 | 47 | adantr 389 |
. . . . . . . 8
⊢ ((φ ⋀ z = A) →
(∀y(φ → A ∈ x)
→ A ∈ x)) |
| 49 | | eleq1 1532 |
. . . . . . . . 9
⊢ (z =
A → (z ∈ x
↔ A ∈ x)) |
| 50 | 49 | adantl 388 |
. . . . . . . 8
⊢ ((φ ⋀ z = A) →
(z ∈ x ↔ A
∈ x)) |
| 51 | 48, 50 | sylibrd 204 |
. . . . . . 7
⊢ ((φ ⋀ z = A) →
(∀y(φ → A ∈ x)
→ z ∈ x)) |
| 52 | 51 | 19.21aiv 1285 |
. . . . . 6
⊢ ((φ ⋀ z = A) →
∀x(∀y(φ →
A ∈ x) → z
∈ x)) |
| 53 | | visset 1810 |
. . . . . . 7
⊢ z
∈ V |
| 54 | 53 | elintab 2540 |
. . . . . 6
⊢ (z
∈ ∩{x∣∀y(φ →
A ∈ x)} ↔ ∀x(∀y(φ →
A ∈ x) → z
∈ x)) |
| 55 | 52, 54 | sylibr 200 |
. . . . 5
⊢ ((φ ⋀ z = A) →
z ∈ ∩{x∣∀y(φ →
A ∈ x)}) |
| 56 | 45, 55 | 19.23ai 1063 |
. . . 4
⊢ (∃y(φ ⋀
z = A)
→ z ∈ ∩{x∣∀y(φ →
A ∈ x)}) |
| 57 | 56 | abssi 2119 |
. . 3
⊢ {z∣∃y(φ ⋀
z = A)}
⊆ ∩{x∣∀y(φ →
A ∈ x)} |
| 58 | 42, 57 | eqssi 2075 |
. 2
⊢ ∩{x∣∀y(φ →
A ∈ x)} = {z∣∃y(φ ⋀
z = A)} |
| 59 | 58, 4 | eqtr 1493 |
1
⊢ ∩{x∣∀y(φ →
A ∈ x)} = {x∣∃y(φ ⋀
x = A)} |