Proof of Theorem bndrank
| Step | Hyp | Ref
| Expression |
| 1 | | visset 1350 |
. . . . . 6
⊢ y
∈ V |
| 2 | 1 | rankid 3516 |
. . . . 5
⊢ y
∈ (R1 ‘suc (rank ‘y)) |
| 3 | | eloni 2209 |
. . . . . . . 8
⊢ (x
∈ On → Ord x) |
| 4 | | rankon 3515 |
. . . . . . . . . 10
⊢ (rank ‘y) ∈ On |
| 5 | 4 | onord 2343 |
. . . . . . . . 9
⊢ Ord (rank ‘y) |
| 6 | | ordsucsssuc 2325 |
. . . . . . . . 9
⊢ ((Ord (rank ‘y) ∧ Ord x)
→ ((rank ‘y) ⊆ x ↔ suc (rank ‘y) ⊆ suc x)) |
| 7 | 5, 6 | mpan 518 |
. . . . . . . 8
⊢ (Ord x
→ ((rank ‘y) ⊆ x ↔ suc (rank ‘y) ⊆ suc x)) |
| 8 | 3, 7 | syl 12 |
. . . . . . 7
⊢ (x
∈ On → ((rank ‘y) ⊆
x ↔ suc (rank ‘y) ⊆ suc x)) |
| 9 | | suceloni 2314 |
. . . . . . . 8
⊢ (x
∈ On → suc x ∈ On) |
| 10 | 4 | onsuc 2353 |
. . . . . . . . 9
⊢ suc (rank ‘y) ∈ On |
| 11 | | r1ord3 3501 |
. . . . . . . . 9
⊢ ((suc (rank ‘y) ∈ On ∧ suc x ∈ On) → (suc (rank ‘y) ⊆ suc x
→ (R1 ‘suc (rank ‘y)) ⊆ (R1 ‘suc
x))) |
| 12 | 10, 11 | mpan 518 |
. . . . . . . 8
⊢ (suc x
∈ On → (suc (rank ‘y)
⊆ suc x → (R1
‘suc (rank ‘y)) ⊆
(R1 ‘suc x))) |
| 13 | 9, 12 | syl 12 |
. . . . . . 7
⊢ (x
∈ On → (suc (rank ‘y)
⊆ suc x → (R1
‘suc (rank ‘y)) ⊆
(R1 ‘suc x))) |
| 14 | 8, 13 | sylbid 178 |
. . . . . 6
⊢ (x
∈ On → ((rank ‘y) ⊆
x → (R1 ‘suc
(rank ‘y)) ⊆
(R1 ‘suc x))) |
| 15 | | ssel 1502 |
. . . . . 6
⊢ ((R1 ‘suc (rank
‘y)) ⊆ (R1
‘suc x) → (y ∈ (R1 ‘suc (rank
‘y)) → y ∈ (R1 ‘suc x))) |
| 16 | 14, 15 | syl6 23 |
. . . . 5
⊢ (x
∈ On → ((rank ‘y) ⊆
x → (y ∈ (R1 ‘suc (rank
‘y)) → y ∈ (R1 ‘suc x)))) |
| 17 | 2, 16 | mpii 45 |
. . . 4
⊢ (x
∈ On → ((rank ‘y) ⊆
x → y ∈ (R1 ‘suc x))) |
| 18 | 17 | r19.20sdv 1257 |
. . 3
⊢ (x
∈ On → (∀y ∈ A (rank ‘y) ⊆ x
→ ∀y ∈ A y ∈
(R1 ‘suc x))) |
| 19 | | dfss3 1498 |
. . . 4
⊢ (A
⊆ (R1 ‘suc x)
↔ ∀y ∈ A y ∈
(R1 ‘suc x)) |
| 20 | | fvex 2838 |
. . . . 5
⊢ (R1 ‘suc x) ∈ V |
| 21 | 20 | ssex 1700 |
. . . 4
⊢ (A
⊆ (R1 ‘suc x)
→ A ∈ V) |
| 22 | 19, 21 | sylbir 176 |
. . 3
⊢ (∀y ∈ A
y ∈ (R1 ‘suc
x) → A ∈ V) |
| 23 | 18, 22 | syl6 23 |
. 2
⊢ (x
∈ On → (∀y ∈ A (rank ‘y) ⊆ x
→ A ∈ V)) |
| 24 | 23 | r19.23aiv 1284 |
1
⊢ (∃x ∈ On ∀y ∈ A (rank
‘y) ⊆ x → A
∈ V) |