# Math, logic symbol for "instance of"

I saw a discussion of a possible symbol for "example," but I need "example/instance of." There is of course

$a \in S$

which is a is a member of/in S, but is there a specific way of stating

$a "instanceOfSymbol" S$ ?

• "If $a$ satisfies _______ then..." May 23, 2015 at 15:58
• What you're asking isn't exactly clear; could you give a concrete example? May 23, 2015 at 15:58
• Symbols themselves are just shorthands. There might be such a thing in typed languages, which are becoming more and more common in various theoretical computer science studies, and some foundational studies. May 23, 2015 at 16:00
• "I have a collection of names, $N=\{n~:~n~\text{is a name}\}$, e.g. Bill." Here "e.g. Bill" is interpreted as "Bill" is an example of one of the $n\in N$. E.g. means exempli gratia, loosely translated as for example. May 23, 2015 at 16:03
• If $S$ is precisely the set of instances of $[\text{thing}]$, then the symbols $\in S$ exactly denote "instances of" $[\text{thing}]$ :) Careful if your $[\text{thing}]$ includes too many instances, you'll run into some paradoxes. May 23, 2015 at 16:07