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 ⊊ Mgm

Proof

Step Hyp Ref Expression
1 sgrpmgm ( 𝑥 ∈ Smgrp → 𝑥 ∈ Mgm )
2 1 ssriv Smgrp ⊆ Mgm
3 mgmnsgrpex 𝑥 ∈ Mgm 𝑥 ∉ Smgrp
4 ssexnelpss ( ( Smgrp ⊆ Mgm ∧ ∃ 𝑥 ∈ Mgm 𝑥 ∉ Smgrp ) → Smgrp ⊊ Mgm )
5 2 3 4 mp2an Smgrp ⊊ Mgm