Step | Hyp | Ref
| Expression |
1 | | vex 3436 |
. . . . . . 7
⊢ 𝑢 ∈ V |
2 | | ax6e 2383 |
. . . . . . 7
⊢
∃𝑦 𝑦 = 𝑣 |
3 | 1, 2 | pm3.2i 471 |
. . . . . 6
⊢ (𝑢 ∈ V ∧ ∃𝑦 𝑦 = 𝑣) |
4 | | 19.42v 1957 |
. . . . . . 7
⊢
(∃𝑦(𝑢 ∈ V ∧ 𝑦 = 𝑣) ↔ (𝑢 ∈ V ∧ ∃𝑦 𝑦 = 𝑣)) |
5 | 4 | biimpri 227 |
. . . . . 6
⊢ ((𝑢 ∈ V ∧ ∃𝑦 𝑦 = 𝑣) → ∃𝑦(𝑢 ∈ V ∧ 𝑦 = 𝑣)) |
6 | 3, 5 | e0a 42392 |
. . . . 5
⊢
∃𝑦(𝑢 ∈ V ∧ 𝑦 = 𝑣) |
7 | | isset 3445 |
. . . . . . 7
⊢ (𝑢 ∈ V ↔ ∃𝑥 𝑥 = 𝑢) |
8 | 7 | anbi1i 624 |
. . . . . 6
⊢ ((𝑢 ∈ V ∧ 𝑦 = 𝑣) ↔ (∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) |
9 | 8 | exbii 1850 |
. . . . 5
⊢
(∃𝑦(𝑢 ∈ V ∧ 𝑦 = 𝑣) ↔ ∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) |
10 | 6, 9 | mpbi 229 |
. . . 4
⊢
∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) |
11 | | idn1 42194 |
. . . . . 6
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ¬
∀𝑥 𝑥 = 𝑦 ) |
12 | | hbnae 2432 |
. . . . . . 7
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∀𝑦 ¬ ∀𝑥 𝑥 = 𝑦) |
13 | | hbn1 2138 |
. . . . . . . . . . . 12
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∀𝑥 ¬ ∀𝑥 𝑥 = 𝑦) |
14 | | ax-5 1913 |
. . . . . . . . . . . . . . . 16
⊢ (𝑧 = 𝑣 → ∀𝑥 𝑧 = 𝑣) |
15 | | ax-5 1913 |
. . . . . . . . . . . . . . . 16
⊢ (𝑦 = 𝑣 → ∀𝑧 𝑦 = 𝑣) |
16 | | idn1 42194 |
. . . . . . . . . . . . . . . . . 18
⊢ ( 𝑧 = 𝑦 ▶ 𝑧 = 𝑦 ) |
17 | | equequ1 2028 |
. . . . . . . . . . . . . . . . . 18
⊢ (𝑧 = 𝑦 → (𝑧 = 𝑣 ↔ 𝑦 = 𝑣)) |
18 | 16, 17 | e1a 42247 |
. . . . . . . . . . . . . . . . 17
⊢ ( 𝑧 = 𝑦 ▶ (𝑧 = 𝑣 ↔ 𝑦 = 𝑣) ) |
19 | 18 | in1 42191 |
. . . . . . . . . . . . . . . 16
⊢ (𝑧 = 𝑦 → (𝑧 = 𝑣 ↔ 𝑦 = 𝑣)) |
20 | 14, 15, 19 | dvelimh 2450 |
. . . . . . . . . . . . . . 15
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣)) |
21 | 11, 20 | e1a 42247 |
. . . . . . . . . . . . . 14
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ (𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣) ) |
22 | 21 | in1 42191 |
. . . . . . . . . . . . 13
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣)) |
23 | 22 | alimi 1814 |
. . . . . . . . . . . 12
⊢
(∀𝑥 ¬
∀𝑥 𝑥 = 𝑦 → ∀𝑥(𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣)) |
24 | 13, 23 | syl 17 |
. . . . . . . . . . 11
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∀𝑥(𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣)) |
25 | 11, 24 | e1a 42247 |
. . . . . . . . . 10
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ∀𝑥(𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣) ) |
26 | | 19.41rg 42170 |
. . . . . . . . . 10
⊢
(∀𝑥(𝑦 = 𝑣 → ∀𝑥 𝑦 = 𝑣) → ((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
27 | 25, 26 | e1a 42247 |
. . . . . . . . 9
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) ) |
28 | 27 | in1 42191 |
. . . . . . . 8
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
29 | 28 | alimi 1814 |
. . . . . . 7
⊢
(∀𝑦 ¬
∀𝑥 𝑥 = 𝑦 → ∀𝑦((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
30 | 12, 29 | syl 17 |
. . . . . 6
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∀𝑦((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
31 | 11, 30 | e1a 42247 |
. . . . 5
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ∀𝑦((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) ) |
32 | | exim 1836 |
. . . . 5
⊢
(∀𝑦((∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) → (∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
33 | 31, 32 | e1a 42247 |
. . . 4
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ (∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) ) |
34 | | pm2.27 42 |
. . . 4
⊢
(∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ((∃𝑦(∃𝑥 𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) → ∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣))) |
35 | 10, 33, 34 | e01 42311 |
. . 3
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ) |
36 | | excomim 2163 |
. . 3
⊢
(∃𝑦∃𝑥(𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) |
37 | 35, 36 | e1a 42247 |
. 2
⊢ ( ¬ ∀𝑥 𝑥 = 𝑦 ▶ ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ) |
38 | 37 | in1 42191 |
1
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) |