Why are we sometimes moved to tears by someone else’s suffering? What makes us want to risk our lives to save a stranger? How do we experience and acknowledge the feelings of others over our own, and how does this alter our behaviour? What if we can’t do any of these things, and find it difficult to treat others as anything other than objects?
http://www.thersa.org/events/audio-and-past-events/2011/zero-degrees-of-empathy