| Step |
Hyp |
Ref |
Expression |
| 1 |
|
ee33VD.1 |
⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜃 ) ) ) |
| 2 |
|
ee33VD.2 |
⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜏 ) ) ) |
| 3 |
|
ee33VD.3 |
⊢ ( 𝜃 → ( 𝜏 → 𝜂 ) ) |
| 4 |
1 3
|
syl8 |
⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → ( 𝜏 → 𝜂 ) ) ) ) |
| 5 |
4
|
com4r |
⊢ ( 𝜏 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) |
| 6 |
2 5
|
syl8 |
⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ) |
| 7 |
|
pm2.43cbi |
⊢ ( ( 𝜑 → ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ) ↔ ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ) |
| 8 |
7
|
biimpi |
⊢ ( ( 𝜑 → ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ) → ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ) |
| 9 |
6 8
|
e0a |
⊢ ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) |
| 10 |
|
pm2.43cbi |
⊢ ( ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) ↔ ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) |
| 11 |
10
|
biimpi |
⊢ ( ( 𝜓 → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) → ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ) |
| 12 |
9 11
|
e0a |
⊢ ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) |
| 13 |
|
pm2.43cbi |
⊢ ( ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) ↔ ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) |
| 14 |
13
|
biimpi |
⊢ ( ( 𝜒 → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) → ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) ) |
| 15 |
12 14
|
e0a |
⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 → 𝜂 ) ) ) |