I think "numerically identical" is just a stupid way of saying "they're the same".

In English, at least, there appears to be no good way to differentiate between "this is the same thing" and "this is an exactly similar thing (except that there are at least two of them)". In programming, you can just test whether two objects have the same memory location, but the simplest way to indicate that in English about arbitrary objects is to point out that there's only one item. Hence the need for phrasing like "numerically identical".

Is there a better way?