Theorem topnex 14951

Description: The class of all topologies is a proper class. The proof uses discrete topologies and pwnex 4570. (Contributed by BJ, 2-May-2021.)

Assertion

Ref	Expression
topnex	|- Top e/ _V

Proof of Theorem topnex

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		pwnex 4570	. . . 4 |- { y | E. x y = ~P x } e/ _V
2	1	neli 2509	. . 3 |- -. { y | E. x y = ~P x } e. _V
3		vex 2816	. . . . . . . 8 |- x e. _V
4		distop 14950	. . . . . . . 8 |- ( x e. _V -> ~P x e. Top )
5	3, 4	ax-mp 5	. . . . . . 7 |- ~P x e. Top
6		eleq1 2295	. . . . . . 7 |- ( y = ~P x -> ( y e. Top <-> ~P x e. Top ) )
7	5, 6	mpbiri 168	. . . . . 6 |- ( y = ~P x -> y e. Top )
8	7	exlimiv 1647	. . . . 5 |- ( E. x y = ~P x -> y e. Top )
9	8	abssi 3313	. . . 4 |- { y | E. x y = ~P x } C_ Top
10		ssexg 4249	. . . 4 |- ( ( { y | E. x y = ~P x } C_ Top /\ Top e. _V ) -> { y | E. x y = ~P x } e. _V )
11	9, 10	mpan 424	. . 3 |- ( Top e. _V -> { y | E. x y = ~P x } e. _V )
12	2, 11	mto 668	. 2 |- -. Top e. _V
13	12	nelir 2510	1 |- Top e/ _V

Syntax hints:   = wceq 1398   E.wex 1541   e. wcel 2203   {cab 2218   e/ wnel 2507   _Vcvv 2813   C_ wss 3211   ~Pcpw 3669   Topctop 14862

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2205  ax-14 2206  ax-ext 2214  ax-sep 4228  ax-pow 4287  ax-un 4554

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-nel 2508  df-ral 2525  df-rex 2526  df-v 2815  df-in 3217  df-ss 3224  df-pw 3671  df-sn 3695  df-uni 3915  df-iun 3993  df-top 14863

This theorem is referenced by: (None)