Bernard explained the difference between money and currency. What a central authority requires in payment of taxes, thereby imposing it as legal tender, is money. Taxes lock us into money. Money is the Yang. It promotes competition and scarcity created through hierarchy. Currency is whatever a community chooses as a medium of exchange, thereby accepting it as common tender. Social currency is the Yin.

wealth comprises three key elements: the natural capital (forests, minerals, aquifers, fertile land, etc.), the produced capital (factories, industrial and urban infrastructure, services, machines, etc.) and the intangible capital (education, quality of the institutions, the rule of law, transparency, stability, beliefs and attitudes, etc.)

The third part deepens the analysis by considering the importance of human and institutional capital, and by linking wealth to production. The fourth part reviews existing applications of resource and environmental accounting in developed and developing countries.

In the early 1930s the small town of Worgl in the Austrian Tyrol, suffering like every other town in Europe and America from the Great Depression, took the unlikely step of issuing its own currency.