[hackuser]

> I asked him after what it was about and he told me this dude’s kid was sick this week. Why would I care? Why would our salesman care?

This is the fundemental principle in a way. People naturally care about each other and want to be cared about. It doesn't always work out in practice because many things can get in the way: Time, stress, competing concerns, fear, etc. But we're social animals, down to the biological level. Understanding that about others and about yourself can help you with sales and with many more important human relations.