Proof of Theorem kmlem6
| Step | Hyp | Ref
| Expression |
| 1 | | r19.26 1289 |
. 2
⊢ (∀z ∈ x
(¬ z = ∅ ∧ ∀w ∈ x
(φ → A = ∅)) ↔ (∀z ∈ x ¬
z = ∅ ∧ ∀z ∈ x
∀w ∈ x (φ →
A = ∅))) |
| 2 | | 19.29r 753 |
. . . . 5
⊢ ((∃v v ∈
z ∧ ∀v∀w
∈ x (φ → ¬ v ∈ A))
→ ∃v(v ∈ z ∧
∀w ∈ x (φ →
¬ v ∈ A))) |
| 3 | | df-rex 1206 |
. . . . 5
⊢ (∃v ∈ z
∀w ∈ x (φ →
¬ v ∈ A) ↔ ∃v(v ∈
z ∧ ∀w ∈ x
(φ → ¬ v ∈ A))) |
| 4 | 2, 3 | sylibr 175 |
. . . 4
⊢ ((∃v v ∈
z ∧ ∀v∀w
∈ x (φ → ¬ v ∈ A))
→ ∃v ∈ z ∀w
∈ x (φ → ¬ v ∈ A)) |
| 5 | | n0 1714 |
. . . . 5
⊢ (¬ z = ∅ ↔ ∃v v ∈
z) |
| 6 | 5 | biimp 133 |
. . . 4
⊢ (¬ z = ∅ → ∃v v ∈
z) |
| 7 | | n0i 1712 |
. . . . . . . 8
⊢ (v
∈ A → ¬ A = ∅) |
| 8 | 7 | con2i 89 |
. . . . . . 7
⊢ (A =
∅ → ¬ v ∈ A) |
| 9 | 8 | syl3 18 |
. . . . . 6
⊢ ((φ → A = ∅) → (φ → ¬ v ∈ A)) |
| 10 | 9 | r19.20si 1254 |
. . . . 5
⊢ (∀w ∈ x
(φ → A = ∅) → ∀w ∈ x
(φ → ¬ v ∈ A)) |
| 11 | 10 | 19.21aiv 943 |
. . . 4
⊢ (∀w ∈ x
(φ → A = ∅) → ∀v∀w
∈ x (φ → ¬ v ∈ A)) |
| 12 | 4, 6, 11 | syl2an 349 |
. . 3
⊢ ((¬ z = ∅ ∧ ∀w ∈ x
(φ → A = ∅)) → ∃v ∈ z
∀w ∈ x (φ →
¬ v ∈ A)) |
| 13 | 12 | r19.20si 1254 |
. 2
⊢ (∀z ∈ x
(¬ z = ∅ ∧ ∀w ∈ x
(φ → A = ∅)) → ∀z ∈ x
∃v ∈ z ∀w
∈ x (φ → ¬ v ∈ A)) |
| 14 | 1, 13 | sylbir 176 |
1
⊢ ((∀z ∈ x ¬
z = ∅ ∧ ∀z ∈ x
∀w ∈ x (φ →
A = ∅)) → ∀z ∈ x
∃v ∈ z ∀w
∈ x (φ → ¬ v ∈ A)) |