A few centuries ago, almost everyone had the same job: surviving. This meant growing, gathering, or hunting food and providing oneself with shelter and building bonds with your community and raising children and taking a little time for stories or music or other arts. Each human family created very little beyond what its members needed.
Suddenly, in geologic time, humans started becoming very efficient at providing themselves with food -- which was previously the largest portion of daily needs. That freed up time for us to make more interesting clothes and start writing down our discoveries. It began letting some people divert their time from food tasks to trade and medicine and painting and many more new specialties. With more hours to spend on fascinating new pursuits, those who delved deeply into them became very good at them. Think of how much more someone who works full-time healing others learns about how to do it and how much better he or she becomes than one who does it in the spare hours from farming. Imagine this extra efficiency spreading to every pursuit, until someone gets the idea to print pages from moveable type rather than writing them by hand or the idea to automate and power the weaving previously done with simple tools in off hours.
So, prosperity comes when people have time beyond what they need to spend on survival tasks, and that use that time to create trade goods.
Also, the more people have this surplus time, the more prosperity they create. It would do no good to be the only human in a continent who knew how to make everything that our current civilization builds. If everyone else was busy farming to survive, that knowledge could not recreate the lifestyle we take for granted. At best, the knowledge holder could teach some of that knowledge to some of the neighbors and help a small community live a little better. Hoarding the knowledge would do very little good at all.
So, in my model, the more others are prosperous, the more prosperous I will be myself. A fair market is an efficient way to let people with one advanced skill trade with people with another advanced skill.
There's no room in my idea of prosperity for making trades that make either partner worse.
And this model implies that the most valuable way to spend one's time is in the activities that create the greatest value for the greatest number.
Happy green candle day! Wishing prosperity to myself, to you, and to all the world.