Whether or not these concepts are really proven wrong, I would claim they're not that centeal to economics. The most central idea of economics is that there aren't enough goods for everybody to have what they want. Therefore, you have to distribute the goods somehow.

Some (more or less) fair ways to do that would be to give the goods to those that pay more, or work harder, or wait longer. There are other ways - stealing, cheating, haveing influential friends.

In any case, the scarcity simply won't go away by declaring economics unscientific.