Description: The proper subset relation is a relation. (Contributed by Stefan O'Rear, 2-Nov-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | relrpss | |- Rel [C.] |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-rpss | |- [C.] = { <. x , y >. | x C. y } |
|
2 | 1 | relopabiv | |- Rel [C.] |