A History of Payments — Part I: From Barter to Institutional Trust

People may disagree about the role money should play in our lives, but everyone has to interact with it. Payments cross geographic, cultural, and demographic boundaries: we use them every day, from a Netflix subscription or a morning matcha to rent, tuition, and a taxi ride. AI has significantly accelerated financial technology developments, and we are now approaching another major shift in payments. The new prophecy in the bubble is that agents will increasingly take on the role of making and executing payment decisions on our behalf. This is a special moment in our history, as money is a fundamental concept of human interaction that serves as a foundation for trust, exchange of resources, settlement of obligations, and enable of specialization.

Reflecting on this, I decided to research payments from first principles: how we evolved from barter to metals to now binary code as the way to save and transact our money. This is an important topic for anyone, especially now. Decentralized currencies like crypto and blockchain-based payment technologies like stablecoins have already been developed and are increasingly regulated, while widespread consumer adoption is still unfolding. Looking at the history of payment technology adoption can reveal how trust and consensus around new forms of money develop among the general population and whether today’s emerging technologies show similar signs of successful adoption.

From barter to exchange

Adam Smith famously described the “propensity to truck, barter, and exchange one thing for another” as a trait of human nature. However, there is limited evidence that the instinct to exchange may not be uniquely human. Chimpanzees have been observed trading food, protection, and social services, while researchers taught Capuchin monkeys to exchange aluminum coins for food. Humans, however, went much further, inventing increasingly complex technologies of exchange, which I view as driven in part by the recognition of basic economic concepts.

Early humans began directly exchanging goods and services, recognizing the value of specialization and comparative advantage. The opportunity cost of producing everything individually was often greater than specializing in a particular activity and trading the surplus for something else. As societies evolved into early civilizations, new forms of governance and social organization brought larger groups of people together, creating more complex systems of trade, taxation, and storage of value. These systems increasingly required standardized payment instruments that people on both sides of a transaction could recognize and trust.

Metals and the first money

One of the most important solutions was the use of valuable metals. Unlike water, food, tools, or other objects with an obvious direct use, metals could serve as a shared anchor of value because both parties were willing to recognize and trust their worth. That trust was never automatic: around 1750 BCE, the merchant Ea-nasir received a now-famous complaint from Nanni over the poor quality of copper he had delivered, showing that even early commodity exchange depended not only on the metal itself, but on confidence in its quality and the person providing it. Early forms of metal money were often valued by weight (an idea reflected in the origins of names such as the shekel, which originally referred to a unit of weight). Over time, weighing pieces of metal evolved into standardized coins and other physical representations of value, creating a form of payment that has survived for thousands of years. I classify this first stage as Type 1: Physical Exchange of Physical Value. This is the direct transfer of physical objects that carry or represent value, from barter and precious metals to coins and, eventually, physical cash.

Bills of exchange

Commodity money and coinage made value more portable, standardized, and easier to compare, but metals created a new problem: they were expensive to transport, protect, divide, and verify. As trade expanded across longer distances, merchants began finding ways to transact without physically moving the underlying metal. By the fourteenth century, Italian merchants were increasingly using bills of exchange, which allowed a buyer to promise payment at a specified place and later date; these claims could eventually be transferred to others and used to settle other debts.

This development introduced a fundamentally different concept of payments: instead of transferring something valuable itself, people could transfer a claim to value. Paper money extended this idea much further. China introduced paper money centuries before Europe, with forms of paper currency appearing as early as the seventh century. In Europe, Sweden became the first country to issue banknotes in 1661, while the Bank of England began issuing notes payable to the bearer shortly after its founding in 1694.

Paper money and institutional trust

These early banknotes were not valuable because of the paper they were printed on. Their value came from the promise behind them—the ability to exchange the note for an underlying asset such as gold or silver, and increasingly from trust in the institution making that promise. This allowed economies to use less physical bullion in everyday transactions and made it easier for banks to hold deposits, extend credit, and move larger amounts of value.

But this convenience introduced a new type of risk. With a gold coin, much of the value was physically in your hand. With a banknote or bank deposit, the value depended on whether the issuer could honor its promise. Trust therefore began shifting from the payment instrument itself toward the institution behind it.

Central banks

The development of central banks helped strengthen that trust. The Bank of England was founded in 1694 as a private bank and banker to the government, primarily to help finance England's war with France. Over time, the government increasingly formalized the monetary system around it. The Bank Charter Act of 1844 restricted private banknote issuance in England and Wales and formalized the Bank of England's role in issuing notes.

The first transformation

By this point, payments had gone through their first fundamental transformation. We moved from directly exchanging objects with physical value, to standardized metals and coins, and eventually to paper claims whose value depended increasingly on trust in the institution behind them. The object itself became less important, while the system guaranteeing its value became more important. But money was still largely physical, and moving it between people and institutions remained slow and costly. The next stage of this history would begin separating the movement of money from the movement of physical objects altogether. In Part II, I will look at how checks, banks, the Federal Reserve, cards, and eventually electronic payment networks built the foundations of the payment system we use today.