Proof of Theorem infeq5i
Step | Hyp | Ref
| Expression |
1 | | difexg 5251 |
. 2
⊢ (ω
∈ V → (ω ∖ {∅}) ∈ V) |
2 | | 0ex 5231 |
. . . . 5
⊢ ∅
∈ V |
3 | 2 | snid 4597 |
. . . 4
⊢ ∅
∈ {∅} |
4 | | disj4 4392 |
. . . . . 6
⊢ ((ω
∩ {∅}) = ∅ ↔ ¬ (ω ∖ {∅}) ⊊
ω) |
5 | | disj3 4387 |
. . . . . 6
⊢ ((ω
∩ {∅}) = ∅ ↔ ω = (ω ∖
{∅})) |
6 | 4, 5 | bitr3i 276 |
. . . . 5
⊢ (¬
(ω ∖ {∅}) ⊊ ω ↔ ω = (ω ∖
{∅})) |
7 | | peano1 7735 |
. . . . . . 7
⊢ ∅
∈ ω |
8 | | eleq2 2827 |
. . . . . . 7
⊢ (ω
= (ω ∖ {∅}) → (∅ ∈ ω ↔ ∅
∈ (ω ∖ {∅}))) |
9 | 7, 8 | mpbii 232 |
. . . . . 6
⊢ (ω
= (ω ∖ {∅}) → ∅ ∈ (ω ∖
{∅})) |
10 | 9 | eldifbd 3900 |
. . . . 5
⊢ (ω
= (ω ∖ {∅}) → ¬ ∅ ∈
{∅}) |
11 | 6, 10 | sylbi 216 |
. . . 4
⊢ (¬
(ω ∖ {∅}) ⊊ ω → ¬ ∅ ∈
{∅}) |
12 | 3, 11 | mt4 116 |
. . 3
⊢ (ω
∖ {∅}) ⊊ ω |
13 | | unidif0 5282 |
. . . . 5
⊢ ∪ (ω ∖ {∅}) = ∪ ω |
14 | | limom 7728 |
. . . . . 6
⊢ Lim
ω |
15 | | limuni 6326 |
. . . . . 6
⊢ (Lim
ω → ω = ∪ ω) |
16 | 14, 15 | ax-mp 5 |
. . . . 5
⊢ ω =
∪ ω |
17 | 13, 16 | eqtr4i 2769 |
. . . 4
⊢ ∪ (ω ∖ {∅}) = ω |
18 | 17 | psseq2i 4025 |
. . 3
⊢ ((ω
∖ {∅}) ⊊ ∪ (ω ∖
{∅}) ↔ (ω ∖ {∅}) ⊊
ω) |
19 | 12, 18 | mpbir 230 |
. 2
⊢ (ω
∖ {∅}) ⊊ ∪ (ω ∖
{∅}) |
20 | | psseq1 4022 |
. . . 4
⊢ (𝑥 = (ω ∖ {∅})
→ (𝑥 ⊊ ∪ 𝑥
↔ (ω ∖ {∅}) ⊊ ∪ 𝑥)) |
21 | | unieq 4850 |
. . . . 5
⊢ (𝑥 = (ω ∖ {∅})
→ ∪ 𝑥 = ∪ (ω
∖ {∅})) |
22 | 21 | psseq2d 4028 |
. . . 4
⊢ (𝑥 = (ω ∖ {∅})
→ ((ω ∖ {∅}) ⊊ ∪ 𝑥 ↔ (ω ∖
{∅}) ⊊ ∪ (ω ∖
{∅}))) |
23 | 20, 22 | bitrd 278 |
. . 3
⊢ (𝑥 = (ω ∖ {∅})
→ (𝑥 ⊊ ∪ 𝑥
↔ (ω ∖ {∅}) ⊊ ∪
(ω ∖ {∅}))) |
24 | 23 | spcegv 3536 |
. 2
⊢ ((ω
∖ {∅}) ∈ V → ((ω ∖ {∅}) ⊊ ∪ (ω ∖ {∅}) → ∃𝑥 𝑥 ⊊ ∪ 𝑥)) |
25 | 1, 19, 24 | mpisyl 21 |
1
⊢ (ω
∈ V → ∃𝑥
𝑥 ⊊ ∪ 𝑥) |