Suppose we were connected, our minds all one the same. But we didn't know each others thoughts, just experienced each others pain. It wouldn't be anything physical, we would simply feel our hearts sink, when someone cried or felt down, it'd pull our own heart strings. Well, what would be different? All sorts of things I think, we would watch what we do to others, well aware of our personal link. Actions meticulously thought out, customs surely changed, "walk a mile in my shoes" could be easily arranged. At first we'd hurt each other, on purpose or mistake but as we grow and change, new systems we'd create. War would slowly fall away as all would feel the loss, human nature slowly turning the next step as we evolve.
So suppose you felt the losses, entertain the idea of feeling despair, and if you can't then realize though numb from others it's always there.