Description: A commutative monoid is a monoid. (Contributed by Mario Carneiro, 6-Jan-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | cmnmnd | |- ( G e. CMnd -> G e. Mnd ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqid | |- ( Base ` G ) = ( Base ` G ) |
|
| 2 | eqid | |- ( +g ` G ) = ( +g ` G ) |
|
| 3 | 1 2 | iscmn | |- ( G e. CMnd <-> ( G e. Mnd /\ A. x e. ( Base ` G ) A. y e. ( Base ` G ) ( x ( +g ` G ) y ) = ( y ( +g ` G ) x ) ) ) |
| 4 | 3 | simplbi | |- ( G e. CMnd -> G e. Mnd ) |