Description: The first argument of a binary relation exists. (An artifact of our ordered pair definition.) (Contributed by NM, 4-Jun-1998)
Ref | Expression | ||
---|---|---|---|
Hypothesis | brrelexi.1 | |
|
Assertion | brrelex1i | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | brrelexi.1 | |
|
2 | brrelex1 | |
|
3 | 1 2 | mpan | |