Anthropologists will tell you that in almost every known culture and civilization there is an unspoken understanding that comes with a gift–a reciprocity that, in effect, says this: Because I have done this for you, you have an obligation to return the favor by doing something for me. In some cultures, there are very clear expectations that need to be followed. I remember, years ago, being invited to a child's first birthday celebration in Korea. It was not a balloons and birthday cake sort of thing for the one-year-old, but a very formal gathering of family and friends. Many were dressed in ceremonial attire and there was a veritable feast of wonderful food. But what I most remember is that everyone who attended brought quite expensive gifts or sums of money for the birthday child, and all the gifts were duly noted by the family of the birthday child in a book. With each gift there was an obligation, over a period of years, to return the same value to the donor.