Theorem fbssfi 23775

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 9435	. . . 4 ⊢ (𝐹 ∈ (fBas‘𝑋) → (fi‘𝐹) = ∩ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)})
2		sseq2 3985	. . . . . . . . . . . . . . . 16 ⊢ (𝑡 = (𝑢 ∩ 𝑣) → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ (𝑢 ∩ 𝑣)))
3	2	rexbidv 3164	. . . . . . . . . . . . . . 15 ⊢ (𝑡 = (𝑢 ∩ 𝑣) → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑢 ∩ 𝑣)))
4		inss1 4212	. . . . . . . . . . . . . . . . 17 ⊢ (𝑢 ∩ 𝑣) ⊆ 𝑢
5		simp1r 1199	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → 𝑢 ∈ 𝒫 ∪ 𝐹)
6	5	elpwid 4584	. . . . . . . . . . . . . . . . 17 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → 𝑢 ⊆ ∪ 𝐹)
7	4, 6	sstrid 3970	. . . . . . . . . . . . . . . 16 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ⊆ ∪ 𝐹)
8		vex 3463	. . . . . . . . . . . . . . . . . 18 ⊢ 𝑢 ∈ V
9	8	inex1 5287	. . . . . . . . . . . . . . . . 17 ⊢ (𝑢 ∩ 𝑣) ∈ V
10	9	elpw 4579	. . . . . . . . . . . . . . . 16 ⊢ ((𝑢 ∩ 𝑣) ∈ 𝒫 ∪ 𝐹 ↔ (𝑢 ∩ 𝑣) ⊆ ∪ 𝐹)
11	7, 10	sylibr 234	. . . . . . . . . . . . . . 15 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑢 ∩ 𝑣) ∈ 𝒫 ∪ 𝐹)
12		simpl 482	. . . . . . . . . . . . . . . . 17 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) → 𝐹 ∈ (fBas‘𝑋))
13		simpl 482	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) → 𝑦 ∈ 𝐹)
14		simpl 482	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣) → 𝑧 ∈ 𝐹)
15		fbasssin 23774	. . . . . . . . . . . . . . . . 17 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝑦 ∈ 𝐹 ∧ 𝑧 ∈ 𝐹) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑦 ∩ 𝑧))
16	12, 13, 14, 15	syl3an 1160	. . . . . . . . . . . . . . . 16 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ (𝑦 ∩ 𝑧))
17		ss2in 4220	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝑦 ⊆ 𝑢 ∧ 𝑧 ⊆ 𝑣) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
18	17	ad2ant2l 746	. . . . . . . . . . . . . . . . . . 19 ⊢ (((𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
19	18	3adant1 1130	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝐹 ∈ (fBas‘𝑋) ∧ 𝑢 ∈ 𝒫 ∪ 𝐹) ∧ (𝑦 ∈ 𝐹 ∧ 𝑦 ⊆ 𝑢) ∧ (𝑧 ∈ 𝐹 ∧ 𝑧 ⊆ 𝑣)) → (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣))
20		sstr 3967	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑥 ⊆ (𝑦 ∩ 𝑧) ∧ (𝑦 ∩ 𝑧) ⊆ (𝑢 ∩ 𝑣)) → 𝑥 ⊆ (𝑢 ∩ 𝑣))
21	20	expcom 413	. . . . . . . . . . . . . . . . . 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 3155	. . . . . . . . . . . . . . . 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 3673	. . . . . . . . . . . . . 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 1118	. . . . . . . . . . . . 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 3142	. . . . . . . . . . . 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 3136	. . . . . . . . . . 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 3985	. . . . . . . . . . . . . 14 ⊢ (𝑡 = 𝑣 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝑣))
30	29	rexbidv 3164	. . . . . . . . . . . . 13 ⊢ (𝑡 = 𝑣 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑣))
31		sseq1 3984	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑧 → (𝑥 ⊆ 𝑣 ↔ 𝑧 ⊆ 𝑣))
32	31	cbvrexvw 3221	. . . . . . . . . . . . 13 ⊢ (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑣 ↔ ∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣)
33	30, 32	bitrdi 287	. . . . . . . . . . . 12 ⊢ (𝑡 = 𝑣 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑧 ∈ 𝐹 𝑧 ⊆ 𝑣))
34	33	ralrab 3677	. . . . . . . . . . 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 234	. . . . . . . . . 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 3142	. . . . . . . . 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 3132	. . . . . . . 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 3985	. . . . . . . . . . 11 ⊢ (𝑡 = 𝑢 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝑢))
39	38	rexbidv 3164	. . . . . . . . . 10 ⊢ (𝑡 = 𝑢 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑢))
40		sseq1 3984	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝑥 ⊆ 𝑢 ↔ 𝑦 ⊆ 𝑢))
41	40	cbvrexvw 3221	. . . . . . . . . 10 ⊢ (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑢 ↔ ∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢)
42	39, 41	bitrdi 287	. . . . . . . . 9 ⊢ (𝑡 = 𝑢 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑦 ∈ 𝐹 𝑦 ⊆ 𝑢))
43	42	ralrab 3677	. . . . . . . 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 234	. . . . . . 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 4921	. . . . . . . 8 ⊢ 𝐹 ⊆ 𝒫 ∪ 𝐹
46		ssid 3981	. . . . . . . . . 10 ⊢ 𝑡 ⊆ 𝑡
47		sseq1 3984	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑡 → (𝑥 ⊆ 𝑡 ↔ 𝑡 ⊆ 𝑡))
48	47	rspcev 3601	. . . . . . . . . 10 ⊢ ((𝑡 ∈ 𝐹 ∧ 𝑡 ⊆ 𝑡) → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡)
49	46, 48	mpan2 691	. . . . . . . . 9 ⊢ (𝑡 ∈ 𝐹 → ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡)
50	49	rgen 3053	. . . . . . . 8 ⊢ ∀𝑡 ∈ 𝐹 ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡
51		ssrab 4048	. . . . . . . 8 ⊢ (𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ (𝐹 ⊆ 𝒫 ∪ 𝐹 ∧ ∀𝑡 ∈ 𝐹 ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡))
52	45, 50, 51	mpbir2an 711	. . . . . . 7 ⊢ 𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}
53	44, 52	jctil 519	. . . . . 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 7734	. . . . . . 7 ⊢ (𝐹 ∈ (fBas‘𝑋) → ∪ 𝐹 ∈ V)
55		pwexg 5348	. . . . . . 7 ⊢ (∪ 𝐹 ∈ V → 𝒫 ∪ 𝐹 ∈ V)
56		rabexg 5307	. . . . . . 7 ⊢ (𝒫 ∪ 𝐹 ∈ V → {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ V)
57		sseq2 3985	. . . . . . . . 9 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → (𝐹 ⊆ 𝑧 ↔ 𝐹 ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
58		eleq2 2823	. . . . . . . . . . 11 ⊢ (𝑧 = {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} → ((𝑢 ∩ 𝑣) ∈ 𝑧 ↔ (𝑢 ∩ 𝑣) ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡}))
59	58	raleqbi1dv 3317	. . . . . . . . . 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 3317	. . . . . . . . 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 632	. . . . . . . 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 3655	. . . . . . 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 257	. . . . 5 ⊢ (𝐹 ∈ (fBas‘𝑋) → {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ∈ {𝑧 ∣ (𝐹 ⊆ 𝑧 ∧ ∀𝑢 ∈ 𝑧 ∀𝑣 ∈ 𝑧 (𝑢 ∩ 𝑣) ∈ 𝑧)})
65		intss1 4939	. . . . 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 3993	. . 3 ⊢ (𝐹 ∈ (fBas‘𝑋) → (fi‘𝐹) ⊆ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
68	67	sselda 3958	. 2 ⊢ ((𝐹 ∈ (fBas‘𝑋) ∧ 𝐴 ∈ (fi‘𝐹)) → 𝐴 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡})
69		sseq2 3985	. . . . 5 ⊢ (𝑡 = 𝐴 → (𝑥 ⊆ 𝑡 ↔ 𝑥 ⊆ 𝐴))
70	69	rexbidv 3164	. . . 4 ⊢ (𝑡 = 𝐴 → (∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡 ↔ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴))
71	70	elrab 3671	. . 3 ⊢ (𝐴 ∈ {𝑡 ∈ 𝒫 ∪ 𝐹 ∣ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝑡} ↔ (𝐴 ∈ 𝒫 ∪ 𝐹 ∧ ∃𝑥 ∈ 𝐹 𝑥 ⊆ 𝐴))
72	71	simprbi 496	. 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 206   ∧ wa 395   ∧ w3a 1086   = wceq 1540   ∈ wcel 2108  {cab 2713  ∀wral 3051  ∃wrex 3060  {crab 3415  Vcvv 3459   ∩ cin 3925   ⊆ wss 3926  𝒫 cpw 4575  ∪ cuni 4883  ∩ cint 4922  ‘cfv 6531  ficfi 9422  fBascfbas 21303

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 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2157  ax-12 2177  ax-ext 2707  ax-sep 5266  ax-nul 5276  ax-pow 5335  ax-pr 5402  ax-un 7729

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3or 1087  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2065  df-mo 2539  df-eu 2568  df-clab 2714  df-cleq 2727  df-clel 2809  df-nfc 2885  df-ne 2933  df-nel 3037  df-ral 3052  df-rex 3061  df-reu 3360  df-rab 3416  df-v 3461  df-sbc 3766  df-csb 3875  df-dif 3929  df-un 3931  df-in 3933  df-ss 3943  df-pss 3946  df-nul 4309  df-if 4501  df-pw 4577  df-sn 4602  df-pr 4604  df-op 4608  df-uni 4884  df-int 4923  df-br 5120  df-opab 5182  df-mpt 5202  df-tr 5230  df-id 5548  df-eprel 5553  df-po 5561  df-so 5562  df-fr 5606  df-we 5608  df-xp 5660  df-rel 5661  df-cnv 5662  df-co 5663  df-dm 5664  df-rn 5665  df-res 5666  df-ima 5667  df-ord 6355  df-on 6356  df-lim 6357  df-suc 6358  df-iota 6484  df-fun 6533  df-fn 6534  df-f 6535  df-f1 6536  df-fo 6537  df-f1o 6538  df-fv 6539  df-om 7862  df-1o 8480  df-2o 8481  df-en 8960  df-fin 8963  df-fi 9423  df-fbas 21312

This theorem is referenced by:  fbssint  23776  fbunfip  23807  fmfnfmlem1  23892  fmfnfmlem4  23895