Metamath Proof Explorer


Theorem sspwimpVD

Description: The following User's Proof is a Virtual Deduction proof (see wvd1 ) using conjunction-form virtual hypothesis collections. It was completed manually, but has the potential to be completed automatically by a tools program which would invoke Mel L. O'Cat's mmj2 and Norm Megill's Metamath Proof Assistant. sspwimp is sspwimpVD without virtual deductions and was derived from sspwimpVD . (Contributed by Alan Sare, 23-Apr-2015) (Proof modification is discouraged.) (New usage is discouraged.)

1:: |- (. A C_ B ->. A C_ B ).
2:: |- (. .............. x e. ~P A ->. x e. ~P A ).
3:2: |- (. .............. x e. ~P A ->. x C_ A ).
4:3,1: |- (. (. A C_ B ,. x e. ~P A ). ->. x C_ B ).
5:: |- x e.V
6:4,5: |- (. (. A C B ,. x e. ~P A ). ->. x e. ~P B ).
7:6: |- (. A C_ B ->. ( x e. ~P A -> x e. ~P B ) ).
8:7: |- (. A C_ B ->. A. x ( x e. ~P A -> x e. ~P B ) ).
9:8: |- (. A C_ B ->. ~P A C_ ~P B ).
qed:9: |- ( A C_ B -> ~P A C_ ~P B )

Ref Expression
Assertion sspwimpVD
|- ( A C_ B -> ~P A C_ ~P B )

Proof

Step Hyp Ref Expression
1 vex
 |-  x e. _V
2 1 vd01
 |-  (. T. ->. x e. _V ).
3 idn1
 |-  (. A C_ B ->. A C_ B ).
4 idn1
 |-  (. x e. ~P A ->. x e. ~P A ).
5 elpwi
 |-  ( x e. ~P A -> x C_ A )
6 4 5 el1
 |-  (. x e. ~P A ->. x C_ A ).
7 sstr
 |-  ( ( x C_ A /\ A C_ B ) -> x C_ B )
8 7 ancoms
 |-  ( ( A C_ B /\ x C_ A ) -> x C_ B )
9 3 6 8 el12
 |-  (. (. A C_ B ,. x e. ~P A ). ->. x C_ B ).
10 2 9 elpwgdedVD
 |-  (. (. T. ,. (. A C_ B ,. x e. ~P A ). ). ->. x e. ~P B ).
11 2 9 10 un0.1
 |-  (. (. A C_ B ,. x e. ~P A ). ->. x e. ~P B ).
12 11 int2
 |-  (. A C_ B ->. ( x e. ~P A -> x e. ~P B ) ).
13 12 gen11
 |-  (. A C_ B ->. A. x ( x e. ~P A -> x e. ~P B ) ).
14 dfss2
 |-  ( ~P A C_ ~P B <-> A. x ( x e. ~P A -> x e. ~P B ) )
15 14 biimpri
 |-  ( A. x ( x e. ~P A -> x e. ~P B ) -> ~P A C_ ~P B )
16 13 15 el1
 |-  (. A C_ B ->. ~P A C_ ~P B ).
17 16 in1
 |-  ( A C_ B -> ~P A C_ ~P B )