Concisely stated, the problem with empathy (the practice of coming to see as another person does, thereby feeling) is the danger of losing perspective. We approach reality through interpretive vision. When we see through the eyes of another for a prolonged period of time we risk losing touch with our own way of seeing, and also of any way of discriminating which way of seeing captures reality, especially if we lack any other reference point.
This leads me to speculate that empathy should be a community project.