The term natural born citizen does not define itself for me. That is because you haven't spent sufficient time contemplating the various iterations in which it does.
Suppose someone is in orbit when they are born, flying over this and that land willy nilly. How do you know what land they happen to be over when they are counted as "born"?
The only knowable thing about a child, of which no other circumstances of birth are known is it's parentage. You can know this because it can be established with positive proof through DNA testing.
What is the natural means of determining a child's national character? Well, by establishing who is the father, and determining what is his National character.
You can't always prove where a child is born, but you can certainly prove who the child's parents are.
But let us see what an early philosopher of Natural Law (Aristotle) had to say on the subject.
But the citizen whom we are seeking to define is a citizen in the strictest sense, against whom no such exception can be taken, and his special characteristic is that he shares in the administration of justice, and in offices. ...
But in practice a citizen is defined to be one of whom both the parents are citizens;
There is a lot of wisdom at the other end of that link.
Suppose someone is in orbit when they are born, flying over this and that land willy nilly. How do you know what land they happen to be over when they are counted as "born"?The easy answer is to tell you that i will cross that bridge when it appears before me because I know that it never will. For the benefit of those of you who will probably live longer than me, I will suggest that the answer to your question may depend on whether the space ship is American space ship. I know that the United States can prosecute an American who murders another American aboard an American ship even if that ship is moored on the Congo River at the time of the murder. United States v. Flores. So, if the space ship is American, it may not matter what country it was over at the moment of birth.
The only knowable thing about a child, of which no other circumstances of birth are known is it's parentage. You can know this because it can be established with positive proof through DNA testing.
Yes, you can now, but that certainly was not true when the Constitution was written so it might not provide us with any help in determining how the Founders wanted to define natural born citizen. Determining a person's mother was usually pretty straightforward, but the identity of fathers was always a very iffy proposition. And, remember, the question does not even become important until at least 35 years after birth. There are a lot of people who believe that the definition of a word in the Constitution became fixed at the outset and is unchangeable.
As to Aristotle, it seems that he believed that the meaning of citizenship varied with different forms of government. I am not sure that he had had any experience of representative governments such as is contemplated by our Constitution. And, then, of course, if we are searching for the intent of the Founders, then his opinions might not be too important.
But, whatever works for others is fine with me. I am sticking with natural born citizen = citizen at birth.