Step |
Hyp |
Ref |
Expression |
1 |
|
ee33VD.1 |
|- ( ph -> ( ps -> ( ch -> th ) ) ) |
2 |
|
ee33VD.2 |
|- ( ph -> ( ps -> ( ch -> ta ) ) ) |
3 |
|
ee33VD.3 |
|- ( th -> ( ta -> et ) ) |
4 |
1 3
|
syl8 |
|- ( ph -> ( ps -> ( ch -> ( ta -> et ) ) ) ) |
5 |
4
|
com4r |
|- ( ta -> ( ph -> ( ps -> ( ch -> et ) ) ) ) |
6 |
2 5
|
syl8 |
|- ( ph -> ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) ) |
7 |
|
pm2.43cbi |
|- ( ( ph -> ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) ) <-> ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) ) |
8 |
7
|
biimpi |
|- ( ( ph -> ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) ) -> ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) ) |
9 |
6 8
|
e0a |
|- ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) |
10 |
|
pm2.43cbi |
|- ( ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) <-> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) |
11 |
10
|
biimpi |
|- ( ( ps -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) -> ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) ) |
12 |
9 11
|
e0a |
|- ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) |
13 |
|
pm2.43cbi |
|- ( ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) <-> ( ph -> ( ps -> ( ch -> et ) ) ) ) |
14 |
13
|
biimpi |
|- ( ( ch -> ( ph -> ( ps -> ( ch -> et ) ) ) ) -> ( ph -> ( ps -> ( ch -> et ) ) ) ) |
15 |
12 14
|
e0a |
|- ( ph -> ( ps -> ( ch -> et ) ) ) |