If you're referring to the way things are understood currently, that's different. My point was simply that the court did not hold in Marbury vs Madison that the court has final say on all matters of constitutional law.
It goes to the reason why the pro-abortion forces are so worried about Bush43 getting opportunities to replace two of the sitting SC justices.
You're talking about something else here. SCOTUS can rule one way today and the opposite way tomorrow. But that doesn't mean the law has changed. All that's changed is the extent to which the law's being respected by the court.
It's not different. It's reality! And it's a 200 year old standard of reality.
You're a purist. I'm a realist.