Theorem fbssfi 23561

Description: A filter base contains subsets of its finite intersections. (Contributed by Mario Carneiro, 26-Nov-2013.) (Revised by Stefan O'Rear, 28-Jul-2015.)

Assertion

Ref	Expression
fbssfi	⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝐴 ∈ (fi‘𝐹)) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐹   𝑥,𝑋

Proof of Theorem fbssfi

Dummy variables 𝑡 𝑢 𝑣 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		dffi2 9420	. . . 4 ⊢ (𝐹 ∈ (fBas‘𝑋) → (fi‘𝐹) = ∩ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)})
2		sseq2 4007	. . . . . . . . . . . . . . . 16 ⊢ (𝑡 = (𝑢 ∩ 𝑣) → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ (𝑢 ∩ 𝑣)))
3	2	rexbidv 3176	. . . . . . . . . . . . . . 15 ⊢ (𝑡 = (𝑢 ∩ 𝑣) → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑢 ∩ 𝑣)))
4		inss1 4227	. . . . . . . . . . . . . . . . 17 ⊢ (𝑢 ∩ 𝑣) ⊆ 𝑢
5		simp1r 1196	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → 𝑢 ∈ 𝒫 ∪ 𝐹)
6	5	elpwid 4610	. . . . . . . . . . . . . . . . 17 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → 𝑢 ⊆ ∪ 𝐹)
7	4, 6	sstrid 3992	. . . . . . . . . . . . . . . 16 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ⊆ ∪ 𝐹)
8		vex 3476	. . . . . . . . . . . . . . . . . 18 ⊢ 𝑢 ∈ V
9	8	inex1 5316	. . . . . . . . . . . . . . . . 17 ⊢ (𝑢 ∩ 𝑣) ∈ V
10	9	elpw 4605	. . . . . . . . . . . . . . . 16 ⊢ ((𝑢 ∩ 𝑣) ∈ 𝒫 ∪ 𝐹 ↔ (𝑢 ∩ 𝑣) ⊆ ∪ 𝐹)
11	7, 10	sylibr 233	. . . . . . . . . . . . . . 15 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ∈ 𝒫 ∪ 𝐹)
12		simpl 481	. . . . . . . . . . . . . . . . 17 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) → 𝐹 ∈ (fBas‘𝑋))
13		simpl 481	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) → 𝑦 ∈ 𝐹)
14		simpl 481	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣) → 𝑧 ∈ 𝐹)
15		fbasssin 23560	. . . . . . . . . . . . . . . . 17 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝑦 ∈ 𝐹 ∧ 𝑧 ∈ 𝐹) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑦 ∩ 𝑧))
16	12, 13, 14, 15	syl3an 1158	. . . . . . . . . . . . . . . 16 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑦 ∩ 𝑧))
17		ss2in 4235	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝑦 ⊆ 𝑢 ∧ 𝑧 ⊆ 𝑣) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
18	17	ad2ant2l 742	. . . . . . . . . . . . . . . . . . 19 ⊢ (((𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
19	18	3adant1 1128	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
20		sstr 3989	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑥 ⊆ (𝑦 ∩ 𝑧) ∧ (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣)) → 𝑥 ⊆ (𝑢 ∩ 𝑣))
21	20	expcom 412	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣) → (𝑥 ⊆ (𝑦 ∩ 𝑧) → 𝑥 ⊆ (𝑢 ∩ 𝑣)))
22	19, 21	syl 17	. . . . . . . . . . . . . . . . 17 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑥 ⊆ (𝑦 ∩ 𝑧) → 𝑥 ⊆ (𝑢 ∩ 𝑣)))
23	22	reximdv 3168	. . . . . . . . . . . . . . . 16 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑦 ∩ 𝑧) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑢 ∩ 𝑣)))
24	16, 23	mpd 15	. . . . . . . . . . . . . . 15 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑢 ∩ 𝑣))
25	3, 11, 24	elrabd 3684	. . . . . . . . . . . . . 14 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
26	25	3expa 1116	. . . . . . . . . . . . 13 ⊢ ((((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢)) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
27	26	rexlimdvaa 3154	. . . . . . . . . . . 12 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢)) → (∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣 → (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
28	27	ralrimivw 3148	. . . . . . . . . . 11 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢)) → ∀𝑣 ∈ 𝒫 ∪ 𝐹(∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣 → (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
29		sseq2 4007	. . . . . . . . . . . . . 14 ⊢ (𝑡 = 𝑣 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝑣))
30	29	rexbidv 3176	. . . . . . . . . . . . 13 ⊢ (𝑡 = 𝑣 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑣))
31		sseq1 4006	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑧 → (𝑥 ⊆ 𝑣 ↔ 𝑧 ⊆ 𝑣))
32	31	cbvrexvw 3233	. . . . . . . . . . . . 13 ⊢ (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑣 ↔ ∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣)
33	30, 32	bitrdi 286	. . . . . . . . . . . 12 ⊢ (𝑡 = 𝑣 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣))
34	33	ralrab 3688	. . . . . . . . . . 11 ⊢ (∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ ∀𝑣 ∈ 𝒫 ∪ 𝐹(∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣 → (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
35	28, 34	sylibr 233	. . . . . . . . . 10 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢)) → ∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
36	35	rexlimdvaa 3154	. . . . . . . . 9 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) → (∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢 → ∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
37	36	ralrimiva 3144	. . . . . . . 8 ⊢ (𝐹 ∈ (fBas‘𝑋) → ∀𝑢 ∈ 𝒫 ∪ 𝐹(∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢 → ∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
38		sseq2 4007	. . . . . . . . . . 11 ⊢ (𝑡 = 𝑢 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝑢))
39	38	rexbidv 3176	. . . . . . . . . 10 ⊢ (𝑡 = 𝑢 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑢))
40		sseq1 4006	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝑥 ⊆ 𝑢 ↔ 𝑦 ⊆ 𝑢))
41	40	cbvrexvw 3233	. . . . . . . . . 10 ⊢ (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑢 ↔ ∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢)
42	39, 41	bitrdi 286	. . . . . . . . 9 ⊢ (𝑡 = 𝑢 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢))
43	42	ralrab 3688	. . . . . . . 8 ⊢ (∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ ∀𝑢 ∈ 𝒫 ∪ 𝐹(∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢 → ∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
44	37, 43	sylibr 233	. . . . . . 7 ⊢ (𝐹 ∈ (fBas‘𝑋) → ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
45		pwuni 4948	. . . . . . . 8 ⊢ 𝐹 ⊆ 𝒫 ∪ 𝐹
46		ssid 4003	. . . . . . . . . 10 ⊢ 𝑡 ⊆ 𝑡
47		sseq1 4006	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑡 → (𝑥 ⊆ 𝑡 ↔ 𝑡 ⊆ 𝑡))
48	47	rspcev 3611	. . . . . . . . . 10 ⊢ ((𝑡 ∈ 𝐹 ∧ 𝑡 ⊆ 𝑡) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡)
49	46, 48	mpan2 687	. . . . . . . . 9 ⊢ (𝑡 ∈ 𝐹 → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡)
50	49	rgen 3061	. . . . . . . 8 ⊢ ∀𝑡 ∈ 𝐹 ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡
51		ssrab 4069	. . . . . . . 8 ⊢ (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ (𝐹 ⊆ 𝒫 ∪ 𝐹 ∧ ∀𝑡 ∈ 𝐹 ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡))
52	45, 50, 51	mpbir2an 707	. . . . . . 7 ⊢ 𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}
53	44, 52	jctil 518	. . . . . 6 ⊢ (𝐹 ∈ (fBas‘𝑋) → (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∧ ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
54		uniexg 7732	. . . . . . 7 ⊢ (𝐹 ∈ (fBas‘𝑋) → ∪ 𝐹 ∈ V)
55		pwexg 5375	. . . . . . 7 ⊢ (∪ 𝐹 ∈ V → 𝒫 ∪ 𝐹 ∈ V)
56		rabexg 5330	. . . . . . 7 ⊢ (𝒫 ∪ 𝐹 ∈ V → {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ V)
57		sseq2 4007	. . . . . . . . 9 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → (𝐹 ⊆ 𝑧 ↔ 𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
58		eleq2 2820	. . . . . . . . . . 11 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → ((𝑢 ∩ 𝑣) ∈ 𝑧 ↔ (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
59	58	raleqbi1dv 3331	. . . . . . . . . 10 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → (∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧 ↔ ∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
60	59	raleqbi1dv 3331	. . . . . . . . 9 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → (∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧 ↔ ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
61	57, 60	anbi12d 629	. . . . . . . 8 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → ((𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧) ↔ (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∧ ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})))
62	61	elabg 3665	. . . . . . 7 ⊢ ({𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ V → ({𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)} ↔ (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∧ ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})))
63	54, 55, 56, 62	4syl 19	. . . . . 6 ⊢ (𝐹 ∈ (fBas‘𝑋) → ({𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)} ↔ (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∧ ∀𝑢 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}∀𝑣 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})))
64	53, 63	mpbird 256	. . . . 5 ⊢ (𝐹 ∈ (fBas‘𝑋) → {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)})
65		intss1 4966	. . . . 5 ⊢ ({𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)} → ∩ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)} ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
66	64, 65	syl 17	. . . 4 ⊢ (𝐹 ∈ (fBas‘𝑋) → ∩ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)} ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
67	1, 66	eqsstrd 4019	. . 3 ⊢ (𝐹 ∈ (fBas‘𝑋) → (fi‘𝐹) ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
68	67	sselda 3981	. 2 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝐴 ∈ (fi‘𝐹)) → 𝐴 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
69		sseq2 4007	. . . . 5 ⊢ (𝑡 = 𝐴 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝐴))
70	69	rexbidv 3176	. . . 4 ⊢ (𝑡 = 𝐴 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴))
71	70	elrab 3682	. . 3 ⊢ (𝐴 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ (𝐴 ∈ 𝒫 ∪ 𝐹 ∧ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴))
72	71	simprbi 495	. 2 ⊢ (𝐴 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴)
73	68, 72	syl 17	1 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝐴 ∈ (fi‘𝐹)) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴)

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 394   ∧ w3a 1085   = wceq 1539   ∈ wcel 2104  {cab 2707  ∀wral 3059  ∃wrex 3068  {crab 3430  Vcvv 3472   ∩ cin 3946   ⊆ wss 3947  𝒫 cpw 4601  ∪ cuni 4907  ∩ cint 4949  ‘cfv 6542  ficfi 9407  fBascfbas 21132

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1911  ax-6 1969  ax-7 2009  ax-8 2106  ax-9 2114  ax-10 2135  ax-11 2152  ax-12 2169  ax-ext 2701  ax-sep 5298  ax-nul 5305  ax-pow 5362  ax-pr 5426  ax-un 7727

This theorem depends on definitions:  df-bi 206  df-an 395  df-or 844  df-3or 1086  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2532  df-eu 2561  df-clab 2708  df-cleq 2722  df-clel 2808  df-nfc 2883  df-ne 2939  df-nel 3045  df-ral 3060  df-rex 3069  df-reu 3375  df-rab 3431  df-v 3474  df-sbc 3777  df-csb 3893  df-dif 3950  df-un 3952  df-in 3954  df-ss 3964  df-pss 3966  df-nul 4322  df-if 4528  df-pw 4603  df-sn 4628  df-pr 4630  df-op 4634  df-uni 4908  df-int 4950  df-br 5148  df-opab 5210  df-mpt 5231  df-tr 5265  df-id 5573  df-eprel 5579  df-po 5587  df-so 5588  df-fr 5630  df-we 5632  df-xp 5681  df-rel 5682  df-cnv 5683  df-co 5684  df-dm 5685  df-rn 5686  df-res 5687  df-ima 5688  df-ord 6366  df-on 6367  df-lim 6368  df-suc 6369  df-iota 6494  df-fun 6544  df-fn 6545  df-f 6546  df-f1 6547  df-fo 6548  df-f1o 6549  df-fv 6550  df-om 7858  df-1o 8468  df-er 8705  df-en 8942  df-fin 8945  df-fi 9408  df-fbas 21141

This theorem is referenced by:  fbssint  23562  fbunfip  23593  fmfnfmlem1  23678  fmfnfmlem4  23681