Metamath Proof Explorer


Theorem grpbn0

Description: The base set of a group is not empty. (Contributed by Szymon Jaroszewicz, 3-Apr-2007)

Ref Expression
Hypothesis grpbn0.b B=BaseG
Assertion grpbn0 GGrpB

Proof

Step Hyp Ref Expression
1 grpbn0.b B=BaseG
2 eqid 0G=0G
3 1 2 grpidcl GGrp0GB
4 3 ne0d GGrpB