Step | Hyp | Ref
| Expression |
1 | | rexeq 2662 |
. . 3
⊢ (𝑤 = ∅ → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ ∅ 𝜑)) |
2 | 1 | dcbid 828 |
. 2
⊢ (𝑤 = ∅ →
(DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ ∅ 𝜑)) |
3 | | rexeq 2662 |
. . 3
⊢ (𝑤 = 𝑦 → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ 𝑦 𝜑)) |
4 | 3 | dcbid 828 |
. 2
⊢ (𝑤 = 𝑦 → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ 𝑦 𝜑)) |
5 | | rexeq 2662 |
. . 3
⊢ (𝑤 = (𝑦 ∪ {𝑧}) → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
6 | 5 | dcbid 828 |
. 2
⊢ (𝑤 = (𝑦 ∪ {𝑧}) → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
7 | | rexeq 2662 |
. . 3
⊢ (𝑤 = 𝐴 → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ 𝐴 𝜑)) |
8 | 7 | dcbid 828 |
. 2
⊢ (𝑤 = 𝐴 → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ 𝐴 𝜑)) |
9 | | rex0 3426 |
. . . . 5
⊢ ¬
∃𝑥 ∈ ∅
𝜑 |
10 | 9 | olci 722 |
. . . 4
⊢
(∃𝑥 ∈
∅ 𝜑 ∨ ¬
∃𝑥 ∈ ∅
𝜑) |
11 | | df-dc 825 |
. . . 4
⊢
(DECID ∃𝑥 ∈ ∅ 𝜑 ↔ (∃𝑥 ∈ ∅ 𝜑 ∨ ¬ ∃𝑥 ∈ ∅ 𝜑)) |
12 | 10, 11 | mpbir 145 |
. . 3
⊢
DECID ∃𝑥 ∈ ∅ 𝜑 |
13 | 12 | a1i 9 |
. 2
⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → DECID ∃𝑥 ∈ ∅ 𝜑) |
14 | | simpr 109 |
. . . . . . . . 9
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → [𝑧 / 𝑥]𝜑) |
15 | | sbsbc 2955 |
. . . . . . . . . 10
⊢ ([𝑧 / 𝑥]𝜑 ↔ [𝑧 / 𝑥]𝜑) |
16 | | rexsns 3615 |
. . . . . . . . . 10
⊢
(∃𝑥 ∈
{𝑧}𝜑 ↔ [𝑧 / 𝑥]𝜑) |
17 | 15, 16 | bitr4i 186 |
. . . . . . . . 9
⊢ ([𝑧 / 𝑥]𝜑 ↔ ∃𝑥 ∈ {𝑧}𝜑) |
18 | 14, 17 | sylib 121 |
. . . . . . . 8
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → ∃𝑥 ∈ {𝑧}𝜑) |
19 | 18 | olcd 724 |
. . . . . . 7
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑)) |
20 | | rexun 3302 |
. . . . . . 7
⊢
(∃𝑥 ∈
(𝑦 ∪ {𝑧})𝜑 ↔ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑)) |
21 | 19, 20 | sylibr 133 |
. . . . . 6
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
22 | 21 | orcd 723 |
. . . . 5
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
23 | | df-dc 825 |
. . . . 5
⊢
(DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ↔ (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
24 | 22, 23 | sylibr 133 |
. . . 4
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
25 | | simpr 109 |
. . . . . . . . 9
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → ∃𝑥 ∈ 𝑦 𝜑) |
26 | 25 | orcd 723 |
. . . . . . . 8
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑)) |
27 | 26, 20 | sylibr 133 |
. . . . . . 7
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
28 | 27 | orcd 723 |
. . . . . 6
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
29 | 28, 23 | sylibr 133 |
. . . . 5
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
30 | | simpr 109 |
. . . . . . . . 9
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ 𝑦 𝜑) |
31 | | simpr 109 |
. . . . . . . . . . 11
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → ¬ [𝑧 / 𝑥]𝜑) |
32 | 17 | notbii 658 |
. . . . . . . . . . 11
⊢ (¬
[𝑧 / 𝑥]𝜑 ↔ ¬ ∃𝑥 ∈ {𝑧}𝜑) |
33 | 31, 32 | sylib 121 |
. . . . . . . . . 10
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → ¬ ∃𝑥 ∈ {𝑧}𝜑) |
34 | 33 | adantr 274 |
. . . . . . . . 9
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ {𝑧}𝜑) |
35 | | ioran 742 |
. . . . . . . . 9
⊢ (¬
(∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑) ↔ (¬ ∃𝑥 ∈ 𝑦 𝜑 ∧ ¬ ∃𝑥 ∈ {𝑧}𝜑)) |
36 | 30, 34, 35 | sylanbrc 414 |
. . . . . . . 8
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑)) |
37 | 20 | notbii 658 |
. . . . . . . 8
⊢ (¬
∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ↔ ¬ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑)) |
38 | 36, 37 | sylibr 133 |
. . . . . . 7
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
39 | 38 | olcd 724 |
. . . . . 6
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
40 | 39, 23 | sylibr 133 |
. . . . 5
⊢
(((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
41 | | exmiddc 826 |
. . . . . 6
⊢
(DECID ∃𝑥 ∈ 𝑦 𝜑 → (∃𝑥 ∈ 𝑦 𝜑 ∨ ¬ ∃𝑥 ∈ 𝑦 𝜑)) |
42 | 41 | ad2antlr 481 |
. . . . 5
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ¬ ∃𝑥 ∈ 𝑦 𝜑)) |
43 | 29, 40, 42 | mpjaodan 788 |
. . . 4
⊢
((((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
44 | | simplrr 526 |
. . . . . . 7
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → 𝑧 ∈ (𝐴 ∖ 𝑦)) |
45 | 44 | eldifad 3127 |
. . . . . 6
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → 𝑧 ∈ 𝐴) |
46 | | simp-4r 532 |
. . . . . 6
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → ∀𝑥 ∈ 𝐴 DECID 𝜑) |
47 | | nfs1v 1927 |
. . . . . . . 8
⊢
Ⅎ𝑥[𝑧 / 𝑥]𝜑 |
48 | 47 | nfdc 1647 |
. . . . . . 7
⊢
Ⅎ𝑥DECID [𝑧 / 𝑥]𝜑 |
49 | | sbequ12 1759 |
. . . . . . . 8
⊢ (𝑥 = 𝑧 → (𝜑 ↔ [𝑧 / 𝑥]𝜑)) |
50 | 49 | dcbid 828 |
. . . . . . 7
⊢ (𝑥 = 𝑧 → (DECID 𝜑 ↔ DECID [𝑧 / 𝑥]𝜑)) |
51 | 48, 50 | rspc 2824 |
. . . . . 6
⊢ (𝑧 ∈ 𝐴 → (∀𝑥 ∈ 𝐴 DECID 𝜑 → DECID [𝑧 / 𝑥]𝜑)) |
52 | 45, 46, 51 | sylc 62 |
. . . . 5
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → DECID [𝑧 / 𝑥]𝜑) |
53 | | exmiddc 826 |
. . . . 5
⊢
(DECID [𝑧 / 𝑥]𝜑 → ([𝑧 / 𝑥]𝜑 ∨ ¬ [𝑧 / 𝑥]𝜑)) |
54 | 52, 53 | syl 14 |
. . . 4
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → ([𝑧 / 𝑥]𝜑 ∨ ¬ [𝑧 / 𝑥]𝜑)) |
55 | 24, 43, 54 | mpjaodan 788 |
. . 3
⊢
(((((𝐴 ∈ Fin
∧ ∀𝑥 ∈
𝐴 DECID
𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑) |
56 | 55 | ex 114 |
. 2
⊢ ((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) → (DECID ∃𝑥 ∈ 𝑦 𝜑 → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)) |
57 | | simpl 108 |
. 2
⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → 𝐴 ∈ Fin) |
58 | 2, 4, 6, 8, 13, 56, 57 | findcard2sd 6858 |
1
⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → DECID ∃𝑥 ∈ 𝐴 𝜑) |