It’s a question that he asks, too. It could become a real question for test tube babies to ask themselves should we ever get to that point in cloning, creating a potential existential crisis in future generations. Right now, it acts as a hypothetical, something that doesn’t need to be answered (do we have souls, either? There’s no way of actually knowing, but depending on our upbringing, we’re asked to believe that yes, we do), or if it does, it’s something that we can approach from the relatively safety of thinking about literature. Does Superboy have a soul? Does Frankenstein’s monster?
It can provide a lot of comfort to only have to think about things in abstract.