I am working through this thought, which came to me this morning while thinking about how to make a happy society.
"I should be free to do what I want."
The substantive moral argument is over whether the more important part of this claim is "free to do" or "what I want."
The substantive ethical argument is over whether the more important part is whether social structures ought to try to guarantee the "should be" or try to shape the "what I want."
I believe the ancients, including all three biblical faiths, take the latter position.
The moderns, including all kinds of Enlightenment thought, take the former.