Imagine a row of cramped stalls on a dusty road somewhere in the Middle East, several hundred years ago. The stalls sit side-by-side on both sides of a dusty street. Some people in the crowd are simply going from one place to another, and some have come to purchase a particular item.

The vendors use all sorts of schemes and strategies to get the attention of the passersby and draw them to their own stall rather than to their neighbor’s.

Each vendor must convince one person at a time that he has the best product compared to all those around him and that it would be a grave mistake to buy from anyone else besides him. The buyer has to be convinced that what he is giving up is nothing in exchange for the value that he is getting in return.