Description: Even the monoid of endofunctions on the empty set is actually a monoid. (Contributed by AV, 31-Jan-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | efmnd0nmnd | |- ( EndoFMnd ` (/) ) e. Mnd | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 0ex | |- (/) e. _V | |
| 2 | eqid | |- ( EndoFMnd ` (/) ) = ( EndoFMnd ` (/) ) | |
| 3 | 2 | efmndmnd | |- ( (/) e. _V -> ( EndoFMnd ` (/) ) e. Mnd ) | 
| 4 | 1 3 | ax-mp | |- ( EndoFMnd ` (/) ) e. Mnd |