Each person works for himself. Each wants to earn and enjoy. And yet in doing so he also works for all the others.

How is this possible?

Because all depend on each other. The shoemaker makes shoes to earn money. But in this way he supplies others with shoes. Self-seeking turns into a contribution for all.

A shared wealth:

In this way, a kind of shared wealth of society arises. Each person can take part in it through his culture and his skill. In this way he secures his livelihood. And through his labor he increases the shared wealth in turn.

Summary: Because all depend on each other, the self-seeking of each person serves all. So a shared wealth arises. Each takes part in it through culture and skill.