Where does the Constitution define "natural born citizen?"
You can argue common law but that would still make him a natural born citizen.
The 14th Amendment is now naturalization at birth. At the time when it was adopted, there was about 4+ million former slaves who were not US citizens. The 14th Amendment naturalized them as citizens. It is a man made law and not natural law. So people considered as 14th Amendment citizens are not natural born citizens.
Where does the Constitution define "natural born citizen?"
You can argue common law but that would still make him a natural born citizen.