What it is about seeing a loving act on the part of one person, towards another, that moves us to tears? Or, when we hear about someone acting in a heroic way to help or save others from injury or death, why it is that we become choked up?

How many of us are moved when we view or hear about someone’s act of generosity—such as aiding a homeless person with getting food or shelter, or providing food, shoes and warm coats to a mother whose children are going without in the dead of winter?