Metamath Proof Explorer


Theorem bj-mndsssmgrp

Description: Monoids are semigroups. (Contributed by BJ, 11-Apr-2024) (Proof modification is discouraged.)

Ref Expression
Assertion bj-mndsssmgrp ⊢ Mnd ⊆ Smgrp

Proof

Step Hyp Ref Expression
1 df-mnd ⊢ Mnd = g ∈ Smgrp | [˙Base g / b]˙ [˙+ g / p]˙ ∃ e ∈ b ∀ x ∈ b e p x = x ∧ x p e = x
2 1 ssrab3 ⊢ Mnd ⊆ Smgrp