| Step |
Hyp |
Ref |
Expression |
| 1 |
|
iseqsetv-clel |
|- ( E. y y = B <-> E. w w = B ) |
| 2 |
|
ax-pr |
|- E. z A. w ( ( w = x \/ w = y ) -> w e. z ) |
| 3 |
|
eqtr3 |
|- ( ( w = B /\ y = B ) -> w = y ) |
| 4 |
3
|
expcom |
|- ( y = B -> ( w = B -> w = y ) ) |
| 5 |
4
|
orim2d |
|- ( y = B -> ( ( w = x \/ w = B ) -> ( w = x \/ w = y ) ) ) |
| 6 |
5
|
imim1d |
|- ( y = B -> ( ( ( w = x \/ w = y ) -> w e. z ) -> ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 7 |
6
|
alimdv |
|- ( y = B -> ( A. w ( ( w = x \/ w = y ) -> w e. z ) -> A. w ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 8 |
7
|
eximdv |
|- ( y = B -> ( E. z A. w ( ( w = x \/ w = y ) -> w e. z ) -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 9 |
2 8
|
mpi |
|- ( y = B -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) |
| 10 |
9
|
exlimiv |
|- ( E. y y = B -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) |
| 11 |
1 10
|
sylbir |
|- ( E. w w = B -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) |
| 12 |
|
ax-pr |
|- E. z A. w ( ( w = x \/ w = x ) -> w e. z ) |
| 13 |
|
alnex |
|- ( A. w -. w = B <-> -. E. w w = B ) |
| 14 |
|
orel2 |
|- ( -. w = B -> ( ( w = x \/ w = B ) -> w = x ) ) |
| 15 |
|
pm2.67-2 |
|- ( ( ( w = x \/ w = x ) -> w e. z ) -> ( w = x -> w e. z ) ) |
| 16 |
14 15
|
syl9 |
|- ( -. w = B -> ( ( ( w = x \/ w = x ) -> w e. z ) -> ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 17 |
16
|
al2imi |
|- ( A. w -. w = B -> ( A. w ( ( w = x \/ w = x ) -> w e. z ) -> A. w ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 18 |
13 17
|
sylbir |
|- ( -. E. w w = B -> ( A. w ( ( w = x \/ w = x ) -> w e. z ) -> A. w ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 19 |
18
|
eximdv |
|- ( -. E. w w = B -> ( E. z A. w ( ( w = x \/ w = x ) -> w e. z ) -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) ) |
| 20 |
12 19
|
mpi |
|- ( -. E. w w = B -> E. z A. w ( ( w = x \/ w = B ) -> w e. z ) ) |
| 21 |
11 20
|
pm2.61i |
|- E. z A. w ( ( w = x \/ w = B ) -> w e. z ) |
| 22 |
|
eqtr3 |
|- ( ( w = A /\ x = A ) -> w = x ) |
| 23 |
22
|
expcom |
|- ( x = A -> ( w = A -> w = x ) ) |
| 24 |
23
|
orim1d |
|- ( x = A -> ( ( w = A \/ w = B ) -> ( w = x \/ w = B ) ) ) |
| 25 |
24
|
imim1d |
|- ( x = A -> ( ( ( w = x \/ w = B ) -> w e. z ) -> ( ( w = A \/ w = B ) -> w e. z ) ) ) |
| 26 |
25
|
alimdv |
|- ( x = A -> ( A. w ( ( w = x \/ w = B ) -> w e. z ) -> A. w ( ( w = A \/ w = B ) -> w e. z ) ) ) |
| 27 |
26
|
eximdv |
|- ( x = A -> ( E. z A. w ( ( w = x \/ w = B ) -> w e. z ) -> E. z A. w ( ( w = A \/ w = B ) -> w e. z ) ) ) |
| 28 |
21 27
|
mpi |
|- ( x = A -> E. z A. w ( ( w = A \/ w = B ) -> w e. z ) ) |