Step |
Hyp |
Ref |
Expression |
1 |
|
on2ind.1 |
|- ( a = c -> ( ph <-> ps ) ) |
2 |
|
on2ind.2 |
|- ( b = d -> ( ps <-> ch ) ) |
3 |
|
on2ind.3 |
|- ( a = c -> ( th <-> ch ) ) |
4 |
|
on2ind.4 |
|- ( a = X -> ( ph <-> ta ) ) |
5 |
|
on2ind.5 |
|- ( b = Y -> ( ta <-> et ) ) |
6 |
|
on2ind.i |
|- ( ( a e. On /\ b e. On ) -> ( ( A. c e. a A. d e. b ch /\ A. c e. a ps /\ A. d e. b th ) -> ph ) ) |
7 |
|
eqid |
|- { <. x , y >. | ( x e. ( On X. On ) /\ y e. ( On X. On ) /\ ( ( ( 1st ` x ) _E ( 1st ` y ) \/ ( 1st ` x ) = ( 1st ` y ) ) /\ ( ( 2nd ` x ) _E ( 2nd ` y ) \/ ( 2nd ` x ) = ( 2nd ` y ) ) /\ x =/= y ) ) } = { <. x , y >. | ( x e. ( On X. On ) /\ y e. ( On X. On ) /\ ( ( ( 1st ` x ) _E ( 1st ` y ) \/ ( 1st ` x ) = ( 1st ` y ) ) /\ ( ( 2nd ` x ) _E ( 2nd ` y ) \/ ( 2nd ` x ) = ( 2nd ` y ) ) /\ x =/= y ) ) } |
8 |
|
onfr |
|- _E Fr On |
9 |
|
epweon |
|- _E We On |
10 |
|
weso |
|- ( _E We On -> _E Or On ) |
11 |
|
sopo |
|- ( _E Or On -> _E Po On ) |
12 |
9 10 11
|
mp2b |
|- _E Po On |
13 |
|
epse |
|- _E Se On |
14 |
|
predon |
|- ( a e. On -> Pred ( _E , On , a ) = a ) |
15 |
14
|
adantr |
|- ( ( a e. On /\ b e. On ) -> Pred ( _E , On , a ) = a ) |
16 |
|
predon |
|- ( b e. On -> Pred ( _E , On , b ) = b ) |
17 |
16
|
adantl |
|- ( ( a e. On /\ b e. On ) -> Pred ( _E , On , b ) = b ) |
18 |
17
|
raleqdv |
|- ( ( a e. On /\ b e. On ) -> ( A. d e. Pred ( _E , On , b ) ch <-> A. d e. b ch ) ) |
19 |
15 18
|
raleqbidv |
|- ( ( a e. On /\ b e. On ) -> ( A. c e. Pred ( _E , On , a ) A. d e. Pred ( _E , On , b ) ch <-> A. c e. a A. d e. b ch ) ) |
20 |
15
|
raleqdv |
|- ( ( a e. On /\ b e. On ) -> ( A. c e. Pred ( _E , On , a ) ps <-> A. c e. a ps ) ) |
21 |
17
|
raleqdv |
|- ( ( a e. On /\ b e. On ) -> ( A. d e. Pred ( _E , On , b ) th <-> A. d e. b th ) ) |
22 |
19 20 21
|
3anbi123d |
|- ( ( a e. On /\ b e. On ) -> ( ( A. c e. Pred ( _E , On , a ) A. d e. Pred ( _E , On , b ) ch /\ A. c e. Pred ( _E , On , a ) ps /\ A. d e. Pred ( _E , On , b ) th ) <-> ( A. c e. a A. d e. b ch /\ A. c e. a ps /\ A. d e. b th ) ) ) |
23 |
22 6
|
sylbid |
|- ( ( a e. On /\ b e. On ) -> ( ( A. c e. Pred ( _E , On , a ) A. d e. Pred ( _E , On , b ) ch /\ A. c e. Pred ( _E , On , a ) ps /\ A. d e. Pred ( _E , On , b ) th ) -> ph ) ) |
24 |
7 8 12 13 8 12 13 1 2 3 4 5 23
|
xpord2ind |
|- ( ( X e. On /\ Y e. On ) -> et ) |