| Step | Hyp | Ref | Expression |
| 1 |
|
excom |
E. x E. y (p /\ q) -> E. y E. x (p /\ q) |
| 2 |
|
pimex12 |
(P. x p -> a) -> E. x (p /\ a) |
| 3 |
|
exim |
A. x (p /\ a -> E. y (p /\ q)) -> E. x (p /\ a) -> E. x E. y (p /\ q) |
| 4 |
|
anl |
E. y q /\ A. y (q -> b) -> E. y q |
| 5 |
4 |
conv pim |
(P. y q -> b) -> E. y q |
| 6 |
|
ian |
p -> q -> p /\ q |
| 7 |
6 |
eximd |
p -> E. y q -> E. y (p /\ q) |
| 8 |
5, 7 |
syl5 |
p -> (P. y q -> b) -> E. y (p /\ q) |
| 9 |
8 |
imim2d |
p -> (a -> (P. y q -> b)) -> a -> E. y (p /\ q) |
| 10 |
9 |
com12 |
(a -> (P. y q -> b)) -> p -> a -> E. y (p /\ q) |
| 11 |
10 |
impd |
(a -> (P. y q -> b)) -> p /\ a -> E. y (p /\ q) |
| 12 |
11 |
alimi |
A. x (a -> (P. y q -> b)) -> A. x (p /\ a -> E. y (p /\ q)) |
| 13 |
3, 12 |
syl |
A. x (a -> (P. y q -> b)) -> E. x (p /\ a) -> E. x E. y (p /\ q) |
| 14 |
2, 13 |
syl5 |
A. x (a -> (P. y q -> b)) -> (P. x p -> a) -> E. x E. y (p /\ q) |
| 15 |
14 |
impcom |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> E. x E. y (p /\ q) |
| 16 |
1, 15 |
syl |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> E. y E. x (p /\ q) |
| 17 |
|
anim |
((P. x p -> a) -> A. x (p -> a)) ->
(A. x (a -> (P. y q -> b)) -> A. x (a -> A. y (q -> b))) ->
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) ->
A. x (p -> a) /\ A. x (a -> A. y (q -> b)) |
| 18 |
|
anr |
E. x p /\ A. x (p -> a) -> A. x (p -> a) |
| 19 |
18 |
conv pim |
(P. x p -> a) -> A. x (p -> a) |
| 20 |
17, 19 |
ax_mp |
(A. x (a -> (P. y q -> b)) -> A. x (a -> A. y (q -> b))) -> (P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> A. x (p -> a) /\ A. x (a -> A. y (q -> b)) |
| 21 |
|
anr |
E. y q /\ A. y (q -> b) -> A. y (q -> b) |
| 22 |
21 |
conv pim |
(P. y q -> b) -> A. y (q -> b) |
| 23 |
22 |
imim2i |
(a -> (P. y q -> b)) -> a -> A. y (q -> b) |
| 24 |
23 |
alimi |
A. x (a -> (P. y q -> b)) -> A. x (a -> A. y (q -> b)) |
| 25 |
20, 24 |
ax_mp |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> A. x (p -> a) /\ A. x (a -> A. y (q -> b)) |
| 26 |
|
bitr |
(E. x (p /\ q) -> b <-> A. x (p /\ q -> b)) -> (A. x (p /\ q -> b) <-> A. x (p -> q -> b)) -> (E. x (p /\ q) -> b <-> A. x (p -> q -> b)) |
| 27 |
|
eexb |
E. x (p /\ q) -> b <-> A. x (p /\ q -> b) |
| 28 |
26, 27 |
ax_mp |
(A. x (p /\ q -> b) <-> A. x (p -> q -> b)) -> (E. x (p /\ q) -> b <-> A. x (p -> q -> b)) |
| 29 |
|
impexp |
p /\ q -> b <-> p -> q -> b |
| 30 |
29 |
aleqi |
A. x (p /\ q -> b) <-> A. x (p -> q -> b) |
| 31 |
28, 30 |
ax_mp |
E. x (p /\ q) -> b <-> A. x (p -> q -> b) |
| 32 |
31 |
aleqi |
A. y (E. x (p /\ q) -> b) <-> A. y A. x (p -> q -> b) |
| 33 |
|
ralalcomb |
A. x (p -> A. y (q -> b)) <-> A. y A. x (p -> q -> b) |
| 34 |
|
imim2 |
(a -> A. y (q -> b)) -> (p -> a) -> p -> A. y (q -> b) |
| 35 |
34 |
com12 |
(p -> a) -> (a -> A. y (q -> b)) -> p -> A. y (q -> b) |
| 36 |
35 |
al2imi |
A. x (p -> a) -> A. x (a -> A. y (q -> b)) -> A. x (p -> A. y (q -> b)) |
| 37 |
36 |
imp |
A. x (p -> a) /\ A. x (a -> A. y (q -> b)) -> A. x (p -> A. y (q -> b)) |
| 38 |
33, 37 |
sylib |
A. x (p -> a) /\ A. x (a -> A. y (q -> b)) -> A. y A. x (p -> q -> b) |
| 39 |
32, 38 |
sylibr |
A. x (p -> a) /\ A. x (a -> A. y (q -> b)) -> A. y (E. x (p /\ q) -> b) |
| 40 |
25, 39 |
rsyl |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> A. y (E. x (p /\ q) -> b) |
| 41 |
16, 40 |
iand |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> E. y E. x (p /\ q) /\ A. y (E. x (p /\ q) -> b) |
| 42 |
41 |
conv pim |
(P. x p -> a) /\ A. x (a -> (P. y q -> b)) -> (P. y E. x (p /\ q) -> b) |
| 43 |
42 |
exp |
(P. x p -> a) -> A. x (a -> (P. y q -> b)) -> (P. y E. x (p /\ q) -> b) |