Money was created many times in many places. Its development required no technological breakthroughs—it was a purely mental revolution. Despite the persistent trend toward monetary quantification and financialization of society as a whole, money remains a mystery. Money is taken as a common denominator of value. Modern capitalism experiences and has to cope with new forms of money. Money remains scarce in an economy that no longer is merely a commodities-producing machine but a sophisticated monetary engine. New financial instruments, for example, collateralized debt obligations, trading in options, and complex packages of securitization are examples of novel forms of money originating in global financial markets. Money is more than a mute background noise or silent currency. Money facilitates social interaction. It reduces the complications of interacting with strangers. The observation about the exchangeability or exchange opportunities of money refers, in other words, to the inherent reflexivity of money.