Metamath Proof Explorer


Theorem sgrpssmgm

Description: The class of all semigroups is a proper subclass of the class of all magmas. (Contributed by AV, 29-Jan-2020)

Ref Expression
Assertion sgrpssmgm
|- Smgrp C. Mgm

Proof

Step Hyp Ref Expression
1 sgrpmgm
 |-  ( x e. Smgrp -> x e. Mgm )
2 1 ssriv
 |-  Smgrp C_ Mgm
3 mgmnsgrpex
 |-  E. x e. Mgm x e/ Smgrp
4 ssexnelpss
 |-  ( ( Smgrp C_ Mgm /\ E. x e. Mgm x e/ Smgrp ) -> Smgrp C. Mgm )
5 2 3 4 mp2an
 |-  Smgrp C. Mgm