People want each other to share in their beliefs. This subconsciously causes them to try to change others into sharing their perception.
In close relationships people tend to empathize with each other. By empathizing, they see each other’s perspective and often combine their perceptions. This can result in one of them being able to speculate and influence what the other perceives.
For example, Omar is watching a television show with some of his friends. When a commercial comes on with an attractive woman, he makes a comment about how good looking she is. His friends completely disagree and start pointing out all of her flaws. Omar is now in a position to change his own perception by noticing the flaws and agreeing with his friends. Alternatively, Omar may try to change the group’s perception and explain why he thinks she’s attractive. If the view become unanimous, the group of friends would now share a common perception.