"Shifted one ground" is a phrase which refers to when a person modifies their views or beliefs on a certain topic. There are several synonyms that can be used to describe this concept such as "changed one's perspective", "altered one's stance", "adjusted one's position" or "revised one's opinion". These synonyms express the idea that someone has made a conscious decision to rethink their point of view and have moved away from their original thoughts. Whatever the reason may be for this shift, it is important to consider all sides of an argument before arriving at a final, well-informed conclusion.