Not so fast. Where does it define them? It doesn't. It references citizens, natural born citizens and naturalized citizens. No where in the constitution does it say all people are either naturalized or natural born. So it's important to understand what the founders thought those terms meant.
Point taken. It would have been more accurate to say that the Constitution identifies two, and only two, classes of citizen: naturalized and natural-born.
No where in the constitution does it say all people are either naturalized or natural born.
Those are the only two forms of citizenship specifically mentioned in the Constitution. So by default if you are not one then you are the other.
So it's important to understand what the founders thought those terms meant.
If the founders has wanted their definition to be the definitive one then I would expect they would have incorporated it into the Constitution itself. But they did not. Nor did they define it in their writings or during the debates. So if you're trying to read their minds then one definition is as good as another.