Restorationism is a way of thinking where people focus on trying to get things back to how they were in the past. For example, if someone wanted to restore a precious painting that was very old, they might try to carefully clean the canvas and use special paint to repair any cracks or missing pieces. People who believe in restorationism also sometimes think that it would be good if society and culture was more like it was in the past. They might try to bring back old customs and use traditional methods to do things again.