| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | ufilfil 23913 | . . . . 5
⊢ (𝑓 ∈ (UFil‘𝑋) → 𝑓 ∈ (Fil‘𝑋)) | 
| 2 |  | ufilmax 23916 | . . . . . . . 8
⊢ ((𝐹 ∈ (UFil‘𝑋) ∧ 𝑓 ∈ (Fil‘𝑋) ∧ 𝐹 ⊆ 𝑓) → 𝐹 = 𝑓) | 
| 3 | 2 | 3expa 1118 | . . . . . . 7
⊢ (((𝐹 ∈ (UFil‘𝑋) ∧ 𝑓 ∈ (Fil‘𝑋)) ∧ 𝐹 ⊆ 𝑓) → 𝐹 = 𝑓) | 
| 4 | 3 | eqcomd 2742 | . . . . . 6
⊢ (((𝐹 ∈ (UFil‘𝑋) ∧ 𝑓 ∈ (Fil‘𝑋)) ∧ 𝐹 ⊆ 𝑓) → 𝑓 = 𝐹) | 
| 5 | 4 | ex 412 | . . . . 5
⊢ ((𝐹 ∈ (UFil‘𝑋) ∧ 𝑓 ∈ (Fil‘𝑋)) → (𝐹 ⊆ 𝑓 → 𝑓 = 𝐹)) | 
| 6 | 1, 5 | sylan2 593 | . . . 4
⊢ ((𝐹 ∈ (UFil‘𝑋) ∧ 𝑓 ∈ (UFil‘𝑋)) → (𝐹 ⊆ 𝑓 → 𝑓 = 𝐹)) | 
| 7 | 6 | ralrimiva 3145 | . . 3
⊢ (𝐹 ∈ (UFil‘𝑋) → ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 → 𝑓 = 𝐹)) | 
| 8 |  | ssid 4005 | . . . 4
⊢ 𝐹 ⊆ 𝐹 | 
| 9 |  | sseq2 4009 | . . . . 5
⊢ (𝑓 = 𝐹 → (𝐹 ⊆ 𝑓 ↔ 𝐹 ⊆ 𝐹)) | 
| 10 | 9 | eqreu 3734 | . . . 4
⊢ ((𝐹 ∈ (UFil‘𝑋) ∧ 𝐹 ⊆ 𝐹 ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 → 𝑓 = 𝐹)) → ∃!𝑓 ∈ (UFil‘𝑋)𝐹 ⊆ 𝑓) | 
| 11 | 8, 10 | mp3an2 1450 | . . 3
⊢ ((𝐹 ∈ (UFil‘𝑋) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 → 𝑓 = 𝐹)) → ∃!𝑓 ∈ (UFil‘𝑋)𝐹 ⊆ 𝑓) | 
| 12 | 7, 11 | mpdan 687 | . 2
⊢ (𝐹 ∈ (UFil‘𝑋) → ∃!𝑓 ∈ (UFil‘𝑋)𝐹 ⊆ 𝑓) | 
| 13 |  | reu6 3731 | . . 3
⊢
(∃!𝑓 ∈
(UFil‘𝑋)𝐹 ⊆ 𝑓 ↔ ∃𝑔 ∈ (UFil‘𝑋)∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) | 
| 14 |  | ibibr 368 | . . . . . . . . . 10
⊢ ((𝑓 = 𝑔 → 𝐹 ⊆ 𝑓) ↔ (𝑓 = 𝑔 → (𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔))) | 
| 15 | 14 | pm5.74ri 272 | . . . . . . . . 9
⊢ (𝑓 = 𝑔 → (𝐹 ⊆ 𝑓 ↔ (𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔))) | 
| 16 |  | sseq2 4009 | . . . . . . . . 9
⊢ (𝑓 = 𝑔 → (𝐹 ⊆ 𝑓 ↔ 𝐹 ⊆ 𝑔)) | 
| 17 | 15, 16 | bitr3d 281 | . . . . . . . 8
⊢ (𝑓 = 𝑔 → ((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ↔ 𝐹 ⊆ 𝑔)) | 
| 18 | 17 | rspcva 3619 | . . . . . . 7
⊢ ((𝑔 ∈ (UFil‘𝑋) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝐹 ⊆ 𝑔) | 
| 19 | 18 | adantll 714 | . . . . . 6
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝐹 ⊆ 𝑔) | 
| 20 |  | ufilfil 23913 | . . . . . . . . . 10
⊢ (𝑔 ∈ (UFil‘𝑋) → 𝑔 ∈ (Fil‘𝑋)) | 
| 21 |  | filelss 23861 | . . . . . . . . . . 11
⊢ ((𝑔 ∈ (Fil‘𝑋) ∧ 𝑥 ∈ 𝑔) → 𝑥 ⊆ 𝑋) | 
| 22 | 21 | ex 412 | . . . . . . . . . 10
⊢ (𝑔 ∈ (Fil‘𝑋) → (𝑥 ∈ 𝑔 → 𝑥 ⊆ 𝑋)) | 
| 23 | 20, 22 | syl 17 | . . . . . . . . 9
⊢ (𝑔 ∈ (UFil‘𝑋) → (𝑥 ∈ 𝑔 → 𝑥 ⊆ 𝑋)) | 
| 24 | 23 | ad2antlr 727 | . . . . . . . 8
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → (𝑥 ∈ 𝑔 → 𝑥 ⊆ 𝑋)) | 
| 25 |  | filsspw 23860 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝐹 ∈ (Fil‘𝑋) → 𝐹 ⊆ 𝒫 𝑋) | 
| 26 | 25 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝐹 ⊆ 𝒫 𝑋) | 
| 27 |  | difss 4135 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝑋 ∖ 𝑥) ⊆ 𝑋 | 
| 28 |  | filtop 23864 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (𝐹 ∈ (Fil‘𝑋) → 𝑋 ∈ 𝐹) | 
| 29 | 28 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝑋 ∈ 𝐹) | 
| 30 | 29 | difexd 5330 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ V) | 
| 31 |  | elpwg 4602 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ ((𝑋 ∖ 𝑥) ∈ V → ((𝑋 ∖ 𝑥) ∈ 𝒫 𝑋 ↔ (𝑋 ∖ 𝑥) ⊆ 𝑋)) | 
| 32 | 30, 31 | syl 17 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((𝑋 ∖ 𝑥) ∈ 𝒫 𝑋 ↔ (𝑋 ∖ 𝑥) ⊆ 𝑋)) | 
| 33 | 27, 32 | mpbiri 258 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ 𝒫 𝑋) | 
| 34 | 33 | snssd 4808 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → {(𝑋 ∖ 𝑥)} ⊆ 𝒫 𝑋) | 
| 35 | 26, 34 | unssd 4191 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ 𝒫 𝑋) | 
| 36 |  | ssun1 4177 | . . . . . . . . . . . . . . . . . . . . 21
⊢ 𝐹 ⊆ (𝐹 ∪ {(𝑋 ∖ 𝑥)}) | 
| 37 |  | filn0 23871 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (𝐹 ∈ (Fil‘𝑋) → 𝐹 ≠ ∅) | 
| 38 | 37 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝐹 ≠ ∅) | 
| 39 |  | ssn0 4403 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝐹 ⊆ (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ∧ 𝐹 ≠ ∅) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ≠ ∅) | 
| 40 | 36, 38, 39 | sylancr 587 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ≠ ∅) | 
| 41 |  | filelss 23861 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32
⊢ ((𝐹 ∈ (Fil‘𝑋) ∧ 𝑓 ∈ 𝐹) → 𝑓 ⊆ 𝑋) | 
| 42 | 41 | ad2ant2rl 749 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → 𝑓 ⊆ 𝑋) | 
| 43 |  | dfss2 3968 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
⊢ (𝑓 ⊆ 𝑋 ↔ (𝑓 ∩ 𝑋) = 𝑓) | 
| 44 | 42, 43 | sylib 218 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → (𝑓 ∩ 𝑋) = 𝑓) | 
| 45 | 44 | sseq1d 4014 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → ((𝑓 ∩ 𝑋) ⊆ 𝑥 ↔ 𝑓 ⊆ 𝑥)) | 
| 46 |  | filss 23862 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
33
⊢ ((𝐹 ∈ (Fil‘𝑋) ∧ (𝑓 ∈ 𝐹 ∧ 𝑥 ⊆ 𝑋 ∧ 𝑓 ⊆ 𝑥)) → 𝑥 ∈ 𝐹) | 
| 47 | 46 | 3exp2 1354 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32
⊢ (𝐹 ∈ (Fil‘𝑋) → (𝑓 ∈ 𝐹 → (𝑥 ⊆ 𝑋 → (𝑓 ⊆ 𝑥 → 𝑥 ∈ 𝐹)))) | 
| 48 | 47 | impcomd 411 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
⊢ (𝐹 ∈ (Fil‘𝑋) → ((𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹) → (𝑓 ⊆ 𝑥 → 𝑥 ∈ 𝐹))) | 
| 49 | 48 | adantr 480 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
⊢ ((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) → ((𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹) → (𝑓 ⊆ 𝑥 → 𝑥 ∈ 𝐹))) | 
| 50 | 49 | imp 406 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → (𝑓 ⊆ 𝑥 → 𝑥 ∈ 𝐹)) | 
| 51 | 45, 50 | sylbid 240 | . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → ((𝑓 ∩ 𝑋) ⊆ 𝑥 → 𝑥 ∈ 𝐹)) | 
| 52 | 51 | con3d 152 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ 𝑓 ∈ 𝐹)) → (¬ 𝑥 ∈ 𝐹 → ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥)) | 
| 53 | 52 | expr 456 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ 𝑥 ⊆ 𝑋) → (𝑓 ∈ 𝐹 → (¬ 𝑥 ∈ 𝐹 → ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥))) | 
| 54 | 53 | com23 86 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ 𝑥 ⊆ 𝑋) → (¬ 𝑥 ∈ 𝐹 → (𝑓 ∈ 𝐹 → ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥))) | 
| 55 | 54 | impr 454 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑓 ∈ 𝐹 → ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥)) | 
| 56 | 55 | imp 406 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) ∧ 𝑓 ∈ 𝐹) → ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥) | 
| 57 |  | ineq2 4213 | . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (𝑔 = (𝑋 ∖ 𝑥) → (𝑓 ∩ 𝑔) = (𝑓 ∩ (𝑋 ∖ 𝑥))) | 
| 58 | 57 | neeq1d 2999 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ (𝑔 = (𝑋 ∖ 𝑥) → ((𝑓 ∩ 𝑔) ≠ ∅ ↔ (𝑓 ∩ (𝑋 ∖ 𝑥)) ≠ ∅)) | 
| 59 | 58 | ralsng 4674 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ ((𝑋 ∖ 𝑥) ∈ V → (∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅ ↔ (𝑓 ∩ (𝑋 ∖ 𝑥)) ≠ ∅)) | 
| 60 |  | inssdif0 4373 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ ((𝑓 ∩ 𝑋) ⊆ 𝑥 ↔ (𝑓 ∩ (𝑋 ∖ 𝑥)) = ∅) | 
| 61 | 60 | necon3bbii 2987 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (¬
(𝑓 ∩ 𝑋) ⊆ 𝑥 ↔ (𝑓 ∩ (𝑋 ∖ 𝑥)) ≠ ∅) | 
| 62 | 59, 61 | bitr4di 289 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ ((𝑋 ∖ 𝑥) ∈ V → (∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅ ↔ ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥)) | 
| 63 | 30, 62 | syl 17 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅ ↔ ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥)) | 
| 64 | 63 | adantr 480 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) ∧ 𝑓 ∈ 𝐹) → (∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅ ↔ ¬ (𝑓 ∩ 𝑋) ⊆ 𝑥)) | 
| 65 | 56, 64 | mpbird 257 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) ∧ 𝑓 ∈ 𝐹) → ∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅) | 
| 66 | 65 | ralrimiva 3145 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ∀𝑓 ∈ 𝐹 ∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅) | 
| 67 |  | filfbas 23857 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝐹 ∈ (Fil‘𝑋) → 𝐹 ∈ (fBas‘𝑋)) | 
| 68 | 67 | ad2antrr 726 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝐹 ∈ (fBas‘𝑋)) | 
| 69 |  | difssd 4136 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ⊆ 𝑋) | 
| 70 |  | ssdif0 4365 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (𝑋 ⊆ 𝑥 ↔ (𝑋 ∖ 𝑥) = ∅) | 
| 71 |  | eqss 3998 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
⊢ (𝑥 = 𝑋 ↔ (𝑥 ⊆ 𝑋 ∧ 𝑋 ⊆ 𝑥)) | 
| 72 | 71 | simplbi2 500 | . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (𝑥 ⊆ 𝑋 → (𝑋 ⊆ 𝑥 → 𝑥 = 𝑋)) | 
| 73 |  | eleq1 2828 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30
⊢ (𝑥 = 𝑋 → (𝑥 ∈ 𝐹 ↔ 𝑋 ∈ 𝐹)) | 
| 74 | 73 | notbid 318 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
⊢ (𝑥 = 𝑋 → (¬ 𝑥 ∈ 𝐹 ↔ ¬ 𝑋 ∈ 𝐹)) | 
| 75 | 74 | biimpcd 249 | . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
⊢ (¬
𝑥 ∈ 𝐹 → (𝑥 = 𝑋 → ¬ 𝑋 ∈ 𝐹)) | 
| 76 | 72, 75 | sylan9 507 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ ((𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹) → (𝑋 ⊆ 𝑥 → ¬ 𝑋 ∈ 𝐹)) | 
| 77 | 76 | adantl 481 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ⊆ 𝑥 → ¬ 𝑋 ∈ 𝐹)) | 
| 78 | 70, 77 | biimtrrid 243 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((𝑋 ∖ 𝑥) = ∅ → ¬ 𝑋 ∈ 𝐹)) | 
| 79 | 78 | necon2ad 2954 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∈ 𝐹 → (𝑋 ∖ 𝑥) ≠ ∅)) | 
| 80 | 29, 79 | mpd 15 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ≠ ∅) | 
| 81 |  | snfbas 23875 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝑋 ∖ 𝑥) ⊆ 𝑋 ∧ (𝑋 ∖ 𝑥) ≠ ∅ ∧ 𝑋 ∈ 𝐹) → {(𝑋 ∖ 𝑥)} ∈ (fBas‘𝑋)) | 
| 82 | 69, 80, 29, 81 | syl3anc 1372 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → {(𝑋 ∖ 𝑥)} ∈ (fBas‘𝑋)) | 
| 83 |  | fbunfip 23878 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ {(𝑋 ∖ 𝑥)} ∈ (fBas‘𝑋)) → (¬ ∅ ∈
(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ↔ ∀𝑓 ∈ 𝐹 ∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅)) | 
| 84 | 68, 82, 83 | syl2anc 584 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (¬ ∅ ∈
(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ↔ ∀𝑓 ∈ 𝐹 ∀𝑔 ∈ {(𝑋 ∖ 𝑥)} (𝑓 ∩ 𝑔) ≠ ∅)) | 
| 85 | 66, 84 | mpbird 257 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ¬ ∅ ∈
(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) | 
| 86 |  | fsubbas 23876 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (𝑋 ∈ 𝐹 → ((fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ∈ (fBas‘𝑋) ↔ ((𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ 𝒫 𝑋 ∧ (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ≠ ∅ ∧ ¬ ∅ ∈
(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))))) | 
| 87 | 29, 86 | syl 17 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ∈ (fBas‘𝑋) ↔ ((𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ 𝒫 𝑋 ∧ (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ≠ ∅ ∧ ¬ ∅ ∈
(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))))) | 
| 88 | 35, 40, 85, 87 | mpbir3and 1342 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ∈ (fBas‘𝑋)) | 
| 89 |  | fgcl 23887 | . . . . . . . . . . . . . . . . . . 19
⊢
((fi‘(𝐹 ∪
{(𝑋 ∖ 𝑥)})) ∈ (fBas‘𝑋) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ∈ (Fil‘𝑋)) | 
| 90 | 88, 89 | syl 17 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ∈ (Fil‘𝑋)) | 
| 91 |  | filssufil 23921 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ∈ (Fil‘𝑋) → ∃𝑓 ∈ (UFil‘𝑋)(𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) | 
| 92 | 90, 91 | syl 17 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ∃𝑓 ∈ (UFil‘𝑋)(𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) | 
| 93 |  | r19.29 3113 | . . . . . . . . . . . . . . . . . 18
⊢
((∀𝑓 ∈
(UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ∧ ∃𝑓 ∈ (UFil‘𝑋)(𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) → ∃𝑓 ∈ (UFil‘𝑋)((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ∧ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓)) | 
| 94 |  | biimp 215 | . . . . . . . . . . . . . . . . . . . . 21
⊢ ((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) → (𝐹 ⊆ 𝑓 → 𝑓 = 𝑔)) | 
| 95 |  | simpll 766 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝐹 ∈ (Fil‘𝑋)) | 
| 96 |  | snex 5435 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ {(𝑋 ∖ 𝑥)} ∈ V | 
| 97 |  | unexg 7764 | . . . . . . . . . . . . . . . . . . . . . . . . . . 27
⊢ ((𝐹 ∈ (Fil‘𝑋) ∧ {(𝑋 ∖ 𝑥)} ∈ V) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ∈ V) | 
| 98 | 95, 96, 97 | sylancl 586 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ∈ V) | 
| 99 |  | ssfii 9460 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢ ((𝐹 ∪ {(𝑋 ∖ 𝑥)}) ∈ V → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ (fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) | 
| 100 | 98, 99 | syl 17 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ (fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) | 
| 101 |  | ssfg 23881 | . . . . . . . . . . . . . . . . . . . . . . . . . 26
⊢
((fi‘(𝐹 ∪
{(𝑋 ∖ 𝑥)})) ∈ (fBas‘𝑋) → (fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ⊆ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 102 | 88, 101 | syl 17 | . . . . . . . . . . . . . . . . . . . . . . . . 25
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})) ⊆ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 103 | 100, 102 | sstrd 3993 | . . . . . . . . . . . . . . . . . . . . . . . 24
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝐹 ∪ {(𝑋 ∖ 𝑥)}) ⊆ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 104 | 103 | unssad 4192 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝐹 ⊆ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 105 |  | sstr2 3989 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝐹 ⊆ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → 𝐹 ⊆ 𝑓)) | 
| 106 | 104, 105 | syl 17 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → 𝐹 ⊆ 𝑓)) | 
| 107 | 106 | imim1d 82 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((𝐹 ⊆ 𝑓 → 𝑓 = 𝑔) → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → 𝑓 = 𝑔))) | 
| 108 |  | sseq2 4009 | . . . . . . . . . . . . . . . . . . . . . . 23
⊢ (𝑓 = 𝑔 → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 ↔ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 109 | 108 | biimpcd 249 | . . . . . . . . . . . . . . . . . . . . . 22
⊢ ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → (𝑓 = 𝑔 → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 110 | 109 | a2i 14 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → 𝑓 = 𝑔) → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 111 | 94, 107, 110 | syl56 36 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) → ((𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓 → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔))) | 
| 112 | 111 | impd 410 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ∧ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 113 | 112 | rexlimdvw 3159 | . . . . . . . . . . . . . . . . . 18
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (∃𝑓 ∈ (UFil‘𝑋)((𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ∧ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 114 | 93, 113 | syl5 34 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ((∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) ∧ ∃𝑓 ∈ (UFil‘𝑋)(𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑓) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 115 | 92, 114 | mpan2d 694 | . . . . . . . . . . . . . . . 16
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔)) | 
| 116 | 115 | imp 406 | . . . . . . . . . . . . . . 15
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔) | 
| 117 | 116 | an32s 652 | . . . . . . . . . . . . . 14
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)}))) ⊆ 𝑔) | 
| 118 |  | snidg 4659 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝑋 ∖ 𝑥) ∈ V → (𝑋 ∖ 𝑥) ∈ {(𝑋 ∖ 𝑥)}) | 
| 119 | 30, 118 | syl 17 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ {(𝑋 ∖ 𝑥)}) | 
| 120 |  | elun2 4182 | . . . . . . . . . . . . . . . . 17
⊢ ((𝑋 ∖ 𝑥) ∈ {(𝑋 ∖ 𝑥)} → (𝑋 ∖ 𝑥) ∈ (𝐹 ∪ {(𝑋 ∖ 𝑥)})) | 
| 121 | 119, 120 | syl 17 | . . . . . . . . . . . . . . . 16
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ (𝐹 ∪ {(𝑋 ∖ 𝑥)})) | 
| 122 | 103, 121 | sseldd 3983 | . . . . . . . . . . . . . . 15
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 123 | 122 | adantlr 715 | . . . . . . . . . . . . . 14
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ (𝑋filGen(fi‘(𝐹 ∪ {(𝑋 ∖ 𝑥)})))) | 
| 124 | 117, 123 | sseldd 3983 | . . . . . . . . . . . . 13
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (𝑋 ∖ 𝑥) ∈ 𝑔) | 
| 125 |  | simpllr 775 | . . . . . . . . . . . . . 14
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝑔 ∈ (UFil‘𝑋)) | 
| 126 |  | simprl 770 | . . . . . . . . . . . . . 14
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → 𝑥 ⊆ 𝑋) | 
| 127 |  | ufilb 23915 | . . . . . . . . . . . . . 14
⊢ ((𝑔 ∈ (UFil‘𝑋) ∧ 𝑥 ⊆ 𝑋) → (¬ 𝑥 ∈ 𝑔 ↔ (𝑋 ∖ 𝑥) ∈ 𝑔)) | 
| 128 | 125, 126,
127 | syl2anc 584 | . . . . . . . . . . . . 13
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → (¬ 𝑥 ∈ 𝑔 ↔ (𝑋 ∖ 𝑥) ∈ 𝑔)) | 
| 129 | 124, 128 | mpbird 257 | . . . . . . . . . . . 12
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ (𝑥 ⊆ 𝑋 ∧ ¬ 𝑥 ∈ 𝐹)) → ¬ 𝑥 ∈ 𝑔) | 
| 130 | 129 | expr 456 | . . . . . . . . . . 11
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ 𝑥 ⊆ 𝑋) → (¬ 𝑥 ∈ 𝐹 → ¬ 𝑥 ∈ 𝑔)) | 
| 131 | 130 | con4d 115 | . . . . . . . . . 10
⊢ ((((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) ∧ 𝑥 ⊆ 𝑋) → (𝑥 ∈ 𝑔 → 𝑥 ∈ 𝐹)) | 
| 132 | 131 | ex 412 | . . . . . . . . 9
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → (𝑥 ⊆ 𝑋 → (𝑥 ∈ 𝑔 → 𝑥 ∈ 𝐹))) | 
| 133 | 132 | com23 86 | . . . . . . . 8
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → (𝑥 ∈ 𝑔 → (𝑥 ⊆ 𝑋 → 𝑥 ∈ 𝐹))) | 
| 134 | 24, 133 | mpdd 43 | . . . . . . 7
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → (𝑥 ∈ 𝑔 → 𝑥 ∈ 𝐹)) | 
| 135 | 134 | ssrdv 3988 | . . . . . 6
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝑔 ⊆ 𝐹) | 
| 136 | 19, 135 | eqssd 4000 | . . . . 5
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝐹 = 𝑔) | 
| 137 |  | simplr 768 | . . . . 5
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝑔 ∈ (UFil‘𝑋)) | 
| 138 | 136, 137 | eqeltrd 2840 | . . . 4
⊢ (((𝐹 ∈ (Fil‘𝑋) ∧ 𝑔 ∈ (UFil‘𝑋)) ∧ ∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔)) → 𝐹 ∈ (UFil‘𝑋)) | 
| 139 | 138 | rexlimdva2 3156 | . . 3
⊢ (𝐹 ∈ (Fil‘𝑋) → (∃𝑔 ∈ (UFil‘𝑋)∀𝑓 ∈ (UFil‘𝑋)(𝐹 ⊆ 𝑓 ↔ 𝑓 = 𝑔) → 𝐹 ∈ (UFil‘𝑋))) | 
| 140 | 13, 139 | biimtrid 242 | . 2
⊢ (𝐹 ∈ (Fil‘𝑋) → (∃!𝑓 ∈ (UFil‘𝑋)𝐹 ⊆ 𝑓 → 𝐹 ∈ (UFil‘𝑋))) | 
| 141 | 12, 140 | impbid2 226 | 1
⊢ (𝐹 ∈ (Fil‘𝑋) → (𝐹 ∈ (UFil‘𝑋) ↔ ∃!𝑓 ∈ (UFil‘𝑋)𝐹 ⊆ 𝑓)) |