>>13234641If you're speaking of sets and categories, an element is a member of set, i.e. an x on the left hand side of "x in y". In standard set theory all members of sets are also sets.
An object is an auxiliary notion in category theory. There it can be seen as one among many things which together provide source and targets of arrows. It's not very off to think of all object of a category as a class (or even a set), so that objects are members too. This is because if you adopt set theoretical foundations, then you merely model categories (again via sets) and don't treat category their, as a first order theory on it's own
