In 1949, businessman Frank McNamara was about to pay for dinner when he realized something terrible: he’d forgotten his wallet. While this scenario isn’t that uncommon, McNamara’s response was. Determined to ensure he’d never be caught without cash again, he invented the Diners Club Card— a wallet-sized piece of cardboard that allowed carriers to dine at associated restaurants and settle their bills at the end of each month.1949 年，商人弗兰克·麦克纳马拉在准备付晚餐账单时，突然发现一个糟糕的情况：他忘带钱包了。虽然这种情况并不少见，但麦克纳马拉的反应却与众不同。为了确保自己不再因为没带现金而陷入窘境，他发明了“大来俱乐部卡”（Diners Club Card）——一张钱包大小的纸板卡片，持卡人可以在合作餐厅用餐，并在每个月底统一结账。

McNamara wasn’t the first person to codify the IOU— there’s evidence of deferred payment systems stretching all the way back to ancient Mesopotamia. In America’s Wild West, ranchers and farmers used metal plates as credit placeholders. And just a few years before McNamara's dining disaster, many department stores and airlines had already begun rolling out reward programs and charge cards.麦克纳马拉并不是第一个把“欠条”制度化的人——早在古代美索不达米亚，就已经有延期支付的系统存在。在美国西部拓荒时期，牧场主和农民们会用金属牌作为信用的凭证。而就在麦克纳马拉“晚餐危机”的前几年，许多百货公司和航空公司已经开始推出奖励计划和记账卡。

But the Diners Club Card was different. Where previous credit arrangements saw one business authorizing credit for one individual, McNamara’s card gave users credit with over two dozen otherwise unassociated businesses. This decentralized credit was revolutionary, and in just one year, the Diners Club Card gained 10,000 users. Soon, several US banks recruited local merchants and launched their own credit programs. For these merchants, credit cards provided increased business and upfront financing. For consumers, the cards offered financial flexibility, allowing them to make larger purchases so long as they could pay them off at the end of each month.但“大来俱乐部卡”却与众不同。以往的信用安排是某一家商户为某一个人提供信用额度，而麦克纳马拉的卡片则让用户在二十多家互不相关的商户中都能获得信用支持。这种去中心化的信用体系是革命性的，仅仅一年时间，大来俱乐部卡就拥有了一万名用户。很快，美国几家银行也招募本地商户，推出了自己的信用计划。对商户来说，信用卡能带来更多生意和预付款资金；而对消费者而言，信用卡则提供了财务上的灵活性，让他们能够进行更大额的消费，只要月底能还清账单即可。