Most people are used to prices that don't change. You go into a store to buy some Quaker Oats, and they're going to cost the same for you as they will for whoever tries to buy them next.
But for a long time, that's not how it worked at all.
For most of human history, you had to haggle over prices before you could buy something. The Quakers were among the first people to commit to fixed prices — and they did it because it was good morals. Turned out, it was also good business. This is the strange story of the long journey of that little piece of paper.
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