Theorem filss 17842

Description: A filter is closed under taking supersets. (Contributed by FL, 20-Jul-2007.) (Revised by Stefan O'Rear, 28-Jul-2015.)

Assertion

Ref	Expression
filss	|- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> B e. F )

Proof of Theorem filss

Dummy variable x is distinct from all other variables.

Step	Hyp	Ref	Expression
1		isfil 17836	. . . 4 |- ( F e. ( Fil ` X ) <-> ( F e. ( fBas ` X ) /\ A. x e. ~P X ( ( F i^i ~P x ) =/= (/) -> x e. F ) ) )
2	1	simprbi 451	. . 3 |- ( F e. ( Fil ` X ) -> A. x e. ~P X ( ( F i^i ~P x ) =/= (/) -> x e. F ) )
3	2	adantr 452	. 2 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> A. x e. ~P X ( ( F i^i ~P x ) =/= (/) -> x e. F ) )
4		elfvdm 5720	. . 3 |- ( F e. ( Fil ` X ) -> X e. dom Fil )
5		simp2 958	. . 3 |- ( ( A e. F /\ B C_ X /\ A C_ B ) -> B C_ X )
6		elpw2g 4327	. . . 4 |- ( X e. dom Fil -> ( B e. ~P X <-> B C_ X ) )
7	6	biimpar 472	. . 3 |- ( ( X e. dom Fil /\ B C_ X ) -> B e. ~P X )
8	4, 5, 7	syl2an 464	. 2 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> B e. ~P X )
9		simpr1 963	. . 3 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> A e. F )
10		simpr3 965	. . . 4 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> A C_ B )
11		elpwg 3770	. . . . 5 |- ( A e. F -> ( A e. ~P B <-> A C_ B ) )
12	9, 11	syl 16	. . . 4 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> ( A e. ~P B <-> A C_ B ) )
13	10, 12	mpbird 224	. . 3 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> A e. ~P B )
14		inelcm 3646	. . 3 |- ( ( A e. F /\ A e. ~P B ) -> ( F i^i ~P B ) =/= (/) )
15	9, 13, 14	syl2anc 643	. 2 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> ( F i^i ~P B ) =/= (/) )
16		pweq 3766	. . . . . 6 |- ( x = B -> ~P x = ~P B )
17	16	ineq2d 3506	. . . . 5 |- ( x = B -> ( F i^i ~P x ) = ( F i^i ~P B ) )
18	17	neeq1d 2584	. . . 4 |- ( x = B -> ( ( F i^i ~P x ) =/= (/) <-> ( F i^i ~P B ) =/= (/) ) )
19		eleq1 2468	. . . 4 |- ( x = B -> ( x e. F <-> B e. F ) )
20	18, 19	imbi12d 312	. . 3 |- ( x = B -> ( ( ( F i^i ~P x ) =/= (/) -> x e. F ) <-> ( ( F i^i ~P B ) =/= (/) -> B e. F ) ) )
21	20	rspccv 3013	. 2 |- ( A. x e. ~P X ( ( F i^i ~P x ) =/= (/) -> x e. F ) -> ( B e. ~P X -> ( ( F i^i ~P B ) =/= (/) -> B e. F ) ) )
22	3, 8, 15, 21	syl3c 59	1 |- ( ( F e. ( Fil ` X ) /\ ( A e. F /\ B C_ X /\ A C_ B ) ) -> B e. F )

Syntax hints:   -> wi 4   <-> wb 177   /\ wa 359   /\ w3a 936   = wceq 1649   e. wcel 1721   =/= wne 2571   A.wral 2670   i^i cin 3283   C_ wss 3284   (/)c0 3592   ~Pcpw 3763   dom cdm 4841   ` cfv 5417   fBascfbas 16648   Filcfil 17834

This theorem is referenced by:  filin  17843  filtop  17844  isfil2  17845  infil  17852  fgfil  17864  fgabs  17868  filcon  17872  filuni  17874  trfil2  17876  trfg  17880  isufil2  17897  ufprim  17898  ufileu  17908  filufint  17909  elfm3  17939  rnelfm  17942  fmfnfmlem2  17944  fmfnfmlem4  17946  flimopn  17964  flimrest  17972  flimfnfcls  18017  fclscmpi  18018  alexsublem  18032  metustOLD  18554  metust  18555  cfil3i  19179  cfilfcls  19184  iscmet3lem2  19202  equivcfil  19209  relcmpcmet  19226  minveclem4  19290  fgmin  26293

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1552  ax-5 1563  ax-17 1623  ax-9 1662  ax-8 1683  ax-13 1723  ax-14 1725  ax-6 1740  ax-7 1745  ax-11 1757  ax-12 1946  ax-ext 2389  ax-sep 4294  ax-nul 4302  ax-pow 4341  ax-pr 4367

This theorem depends on definitions:  df-bi 178  df-or 360  df-an 361  df-3an 938  df-tru 1325  df-ex 1548  df-nf 1551  df-sb 1656  df-eu 2262  df-mo 2263  df-clab 2395  df-cleq 2401  df-clel 2404  df-nfc 2533  df-ne 2573  df-ral 2675  df-rex 2676  df-rab 2679  df-v 2922  df-sbc 3126  df-csb 3216  df-dif 3287  df-un 3289  df-in 3291  df-ss 3298  df-nul 3593  df-if 3704  df-pw 3765  df-sn 3784  df-pr 3785  df-op 3787  df-uni 3980  df-br 4177  df-opab 4231  df-mpt 4232  df-id 4462  df-xp 4847  df-rel 4848  df-cnv 4849  df-co 4850  df-dm 4851  df-rn 4852  df-res 4853  df-ima 4854  df-iota 5381  df-fun 5419  df-fv 5425  df-fil 17835