Do we still need cash? Humans have used all sorts of things as stores of value — rare metals, strings of shells, even jugs of whiskey. Over time the objects have become more ephemeral, from coins to paper to digital forms. Economists see great payoffs in a cashless society: lower costs for businesses and new tools to manage economies, stymie tax evasion and fight money laundering. Critics see an erosion of privacy, frightening new powers for governments and another sign of widening inequality.