| Step |
Hyp |
Ref |
Expression |
| 1 |
|
wevsev.1 |
|- S = { <. x , y >. | ( ( rank ` x ) e. ( rank ` y ) \/ ( ( rank ` x ) = ( rank ` y ) /\ x R y ) ) } |
| 2 |
|
ssv |
|- { z e. _V | ( rank ` z ) = ( rank ` w ) } C_ _V |
| 3 |
|
wess |
|- ( { z e. _V | ( rank ` z ) = ( rank ` w ) } C_ _V -> ( R We _V -> R We { z e. _V | ( rank ` z ) = ( rank ` w ) } ) ) |
| 4 |
2 3
|
ax-mp |
|- ( R We _V -> R We { z e. _V | ( rank ` z ) = ( rank ` w ) } ) |
| 5 |
4
|
ralrimivw |
|- ( R We _V -> A. w e. _V R We { z e. _V | ( rank ` z ) = ( rank ` w ) } ) |
| 6 |
1
|
werankwe2 |
|- ( A. w e. _V R We { z e. _V | ( rank ` z ) = ( rank ` w ) } -> S We _V ) |
| 7 |
5 6
|
syl |
|- ( R We _V -> S We _V ) |
| 8 |
1
|
rankse |
|- S Se _V |
| 9 |
7 8
|
jctir |
|- ( R We _V -> ( S We _V /\ S Se _V ) ) |