| Step |
Hyp |
Ref |
Expression |
| 1 |
|
idn1 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∀ 𝑥 𝑥 = 𝑦 ) |
| 2 |
|
ax6ev |
⊢ ∃ 𝑥 𝑥 = 𝑢 |
| 3 |
|
hba1 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ∀ 𝑥 𝑥 = 𝑦 ) |
| 4 |
|
sp |
⊢ ( ∀ 𝑥 ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 𝑥 = 𝑦 ) |
| 5 |
3 4
|
impbii |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ↔ ∀ 𝑥 ∀ 𝑥 𝑥 = 𝑦 ) |
| 6 |
|
idn2 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 , 𝑥 = 𝑢 ▶ 𝑥 = 𝑢 ) |
| 7 |
|
sp |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → 𝑥 = 𝑦 ) |
| 8 |
1 7
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ 𝑥 = 𝑦 ) |
| 9 |
|
ax7 |
⊢ ( 𝑥 = 𝑦 → ( 𝑥 = 𝑢 → 𝑦 = 𝑢 ) ) |
| 10 |
9
|
com12 |
⊢ ( 𝑥 = 𝑢 → ( 𝑥 = 𝑦 → 𝑦 = 𝑢 ) ) |
| 11 |
6 8 10
|
e21 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 , 𝑥 = 𝑢 ▶ 𝑦 = 𝑢 ) |
| 12 |
|
pm3.2 |
⊢ ( 𝑥 = 𝑢 → ( 𝑦 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 13 |
6 11 12
|
e22 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 , 𝑥 = 𝑢 ▶ ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 14 |
13
|
in2 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 15 |
14
|
in1 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 16 |
15
|
alimi |
⊢ ( ∀ 𝑥 ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 17 |
5 16
|
sylbi |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 18 |
1 17
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∀ 𝑥 ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 19 |
|
exim |
⊢ ( ∀ 𝑥 ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) → ( ∃ 𝑥 𝑥 = 𝑢 → ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 20 |
18 19
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ( ∃ 𝑥 𝑥 = 𝑢 → ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 21 |
|
pm2.27 |
⊢ ( ∃ 𝑥 𝑥 = 𝑢 → ( ( ∃ 𝑥 𝑥 = 𝑢 → ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) → ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 22 |
2 20 21
|
e01 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 23 |
22
|
in1 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 24 |
23
|
axc4i |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑥 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 25 |
1 24
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∀ 𝑥 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 26 |
|
axc11 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ( ∀ 𝑥 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∀ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) ) |
| 27 |
1 25 26
|
e11 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∀ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 28 |
|
19.2 |
⊢ ( ∀ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 29 |
27 28
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∃ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 30 |
|
excomim |
⊢ ( ∃ 𝑦 ∃ 𝑥 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 31 |
29 30
|
e1a |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 32 |
|
idn1 |
⊢ ( 𝑢 = 𝑣 ▶ 𝑢 = 𝑣 ) |
| 33 |
|
idn2 |
⊢ ( 𝑢 = 𝑣 , ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ▶ ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ) |
| 34 |
|
simpr |
⊢ ( ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → 𝑦 = 𝑢 ) |
| 35 |
33 34
|
e2 |
⊢ ( 𝑢 = 𝑣 , ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ▶ 𝑦 = 𝑢 ) |
| 36 |
|
equtrr |
⊢ ( 𝑢 = 𝑣 → ( 𝑦 = 𝑢 → 𝑦 = 𝑣 ) ) |
| 37 |
32 35 36
|
e12 |
⊢ ( 𝑢 = 𝑣 , ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ▶ 𝑦 = 𝑣 ) |
| 38 |
|
simpl |
⊢ ( ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → 𝑥 = 𝑢 ) |
| 39 |
33 38
|
e2 |
⊢ ( 𝑢 = 𝑣 , ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ▶ 𝑥 = 𝑢 ) |
| 40 |
|
pm3.21 |
⊢ ( 𝑦 = 𝑣 → ( 𝑥 = 𝑢 → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 41 |
37 39 40
|
e22 |
⊢ ( 𝑢 = 𝑣 , ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) ▶ ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) |
| 42 |
41
|
in2 |
⊢ ( 𝑢 = 𝑣 ▶ ( ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 43 |
42
|
gen11 |
⊢ ( 𝑢 = 𝑣 ▶ ∀ 𝑦 ( ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 44 |
|
exim |
⊢ ( ∀ 𝑦 ( ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) → ( ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 45 |
43 44
|
e1a |
⊢ ( 𝑢 = 𝑣 ▶ ( ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 46 |
45
|
gen11 |
⊢ ( 𝑢 = 𝑣 ▶ ∀ 𝑥 ( ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 47 |
|
exim |
⊢ ( ∀ 𝑥 ( ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) → ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 48 |
46 47
|
e1a |
⊢ ( 𝑢 = 𝑣 ▶ ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 49 |
48
|
in1 |
⊢ ( 𝑢 = 𝑣 → ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 50 |
|
pm2.04 |
⊢ ( ( 𝑢 = 𝑣 → ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) → ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ( 𝑢 = 𝑣 → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) ) |
| 51 |
50
|
com12 |
⊢ ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ( ( 𝑢 = 𝑣 → ( ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑢 ) → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) → ( 𝑢 = 𝑣 → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) ) |
| 52 |
31 49 51
|
e10 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 ▶ ( 𝑢 = 𝑣 → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |
| 53 |
52
|
in1 |
⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ( 𝑢 = 𝑣 → ∃ 𝑥 ∃ 𝑦 ( 𝑥 = 𝑢 ∧ 𝑦 = 𝑣 ) ) ) |