An advantage of monetary exchange is the clean beginning, and end of the transaction. If someone gives you something, there is a subtler, relationship based, exchange going on. It is a fuzzier world. One where expectations are unclear. How do you say thank you? Will you be called on to act in the future? What are the conditions? In a world where everyone see the world in the same way, culture gives you clarity about how to behave. Unwritten rules, learnt through gossip, and friendships, extend each act from being a transaction to being a relationship. Money allows people who don't speak the same language, or have the same beliefs, to trust each other temporarily. Deep trust requires time, and uncomfortable conversations. Deep trust requires disappointment, pain, tears and a willingness to rebuild. Deep trust is a beautiful thing, built without a clean beginning and end.