Theorem 2pwuninelg 6286

Description: The power set of the power set of the union of a set does not belong to the set. This theorem provides a way of constructing a new set that doesn't belong to a given set. (Contributed by Jim Kingdon, 14-Jan-2020.)

Assertion

Ref	Expression
2pwuninelg	|- ( A e. V -> -. ~P ~P U. A e. A )

Proof of Theorem 2pwuninelg

Step	Hyp	Ref	Expression
1		en2lp 4555	. 2 |- -. ( A e. ~P ~P U. A /\ ~P ~P U. A e. A )
2		pwuni 4194	. . . 4 |- A C_ ~P U. A
3		elpwg 3585	. . . 4 |- ( A e. V -> ( A e. ~P ~P U. A <-> A C_ ~P U. A ) )
4	2, 3	mpbiri 168	. . 3 |- ( A e. V -> A e. ~P ~P U. A )
5		ax-ia3 108	. . 3 |- ( A e. ~P ~P U. A -> ( ~P ~P U. A e. A -> ( A e. ~P ~P U. A /\ ~P ~P U. A e. A ) ) )
6	4, 5	syl 14	. 2 |- ( A e. V -> ( ~P ~P U. A e. A -> ( A e. ~P ~P U. A /\ ~P ~P U. A e. A ) ) )
7	1, 6	mtoi 664	1 |- ( A e. V -> -. ~P ~P U. A e. A )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   e. wcel 2148   C_ wss 3131   ~Pcpw 3577   U.cuni 3811

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 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159  ax-setind 4538

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ral 2460  df-v 2741  df-dif 3133  df-un 3135  df-in 3137  df-ss 3144  df-pw 3579  df-sn 3600  df-pr 3601  df-uni 3812

This theorem is referenced by:  mnfnre  8002