The notion of wrong implies that there is a natural order of ways things should be.
If there is not a Supreme consciousness who ordains that natural order the concept of “right” and “wrong” have no meaning other than “that which I like” and “that which I dislike”, which is fine, but although one’s personal likes and dislikes may be self-evident to one self, no one else is either obligated to agree or conform his behavior to them.
Right and Wrong are only universally “self-evident” because God’s existence is self-evident.
“Right and Wrong are only universally self-evident because Gods existence is self-evident.”
Or may be because we debated it and agreed on few basic things?