Submonoid

Meta

context $\langle\!\langle M,*\rangle\!\rangle$ … monoid
definiendum $\langle\!\langle S,*\rangle\!\rangle\in$ it
inclusion $S\in$ closed monoid subset of $\langle\!\langle M,*\rangle\!\rangle$
exists $e\in S$
postulate $e$ … unit of $\langle\!\langle M,*\rangle\!\rangle$


Subset of

closed monoid subset