“Cash is private by default.
The old world was private by default.
The new world is not private by default.
So we are defaulting into tracking.
Zero knowledge is the defense.”

— Balaji Srinivasan

Money is one of the oldest technologies. It evolved to solve what economists call the problem of the double coincidence of wants. Before money, people bartered goods and services directly. However, this approach had obvious limitations—finding someone who not only had what you wanted but also wanted what you had (in the right quantities on both sides of the trade) was often impractical. For example, if a baker needed shoes but the cobbler didn’t need bread, the baker had to find a third party to facilitate the trade, making the process cumbersome and inefficient.

Over time, societies gradually adopted a common medium of exchange—money—as a natural solution to the inefficiencies of barter. Because of its universal acceptability, money, allowed people to focus on producing what they were most skilled at, rather than on only those goods that they could directly barter with. Said another way, the emergence of money transformed economies from fragmented and limited exchanges into interconnected markets, paving the way for unprecedented specialization, free trade, growth, and cooperation.

Throughout history, money has taken many forms—shells, stones, gold, and paper—but its function remains unchanged: a medium of exchange trusted by those who use it. However, this trust is fragile. Throughout history, those in power have often manipulated money’s value by inflating its supply, resulting in a breakdown of said money’s utility and the economic order it supported. Even a child understands that an oversupply of something diminishes each unit’s worth; yet governments and authorities persist in this folly, at the expense of the broader society.

Alchemy—the attempt to turn base materials into gold—is one of humanity’s oldest desires. Modern-day “alchemists” can be found in government offices and their central banks around the world, where monetary authorities try in vain to create value from nothing by issuing endless fiat currency. Like the alchemists of old, they operate on illusion, believing their money will retain its value long enough to achieve their goals. However, history shows that these illusions are unsustainable, leading to economic distortions, the erosion of wealth, and cultural degradation.

The dominant form of money today is fiat currency—money that derives its value not from inherent qualities but from government decree. The primary flaw of fiat money lies in its centralization and near-zero marginal cost of production. Those who control its supply wield extraordinary power, with the ability to shape economies and societies at will. A clear example is Sri Lanka’s recent economic meltdown, during which the government’s excessive printing of money to finance debt and cover import costs triggered hyperinflation. This led to skyrocketing prices, severe shortages of essentials like fuel and medicine, and widespread protests as citizens struggled to cope with the crisis.

Furthermore, to use modern monetary technologies and institutions, we must sacrifice our privacy for convenience. Banks, credit card companies, and governments have access to every electronic transaction we make. In just the last four years, the percentage of global transactions conducted in cash—the most private medium of exchange—has decreased from 27% to only 16%. Whether maliciously or not, governments’ successful encouragement of a cashless future grants them increased surveillance and enables them to monitor your every move. 

For example, China has already implemented a social credit system that meticulously tracks citizens’ financial transactions, online activities, and certain social behaviors to assign them scores. Low scores may lead to difficulties in finding employment, getting loans, booking flights, and even restricted access to services such as high-speed trains and certain public amenities. By consolidating vast amounts of personal data, the system not only monitors but also controls and influences behavior, demonstrating the extent to which authorities can dominate individuals with the power of controllable, trackable fiat currency in hand.

Even in democracies like the United States, debanking is common among what are called “politically exposed persons”. Recently, a clip of Marc Andreessen on Joe Rogan’s podcast went viral on X, in which he talked about how many people have been kicked out of the banking system for “having the wrong politics and saying unacceptable things.” Scores of famous tech and crypto founders reshared the clip on X, talking about their experiences of getting debanked and the nonsensical reasons for it. I encourage you to watch the clip if you haven’t done so already.

Bitcoin, as its supporters like to say, solves this (partially). Nobody can cut off your access to your funds except by forcibly accessing your private keys, a rather expensive endeavor as you scale up to millions or billions of people. 

But the problem with Bitcoin as it is implemented today is that the entire history is public. Transactions are attributed to random identifiers that, in themselves, carry no information about the person controlling the accounts. However, if users are not extremely careful, network analysis can reveal both the financial behavior and the real identities of the people behind the accounts. (Several companies, such as Chainalysis, now provide such a service.)

A stark example of this weakness is the recent Canadian trucker protests against national policies. Supporters contributed Bitcoin to the movement, but Bitcoin’s transparent nature enabled the government to trace and seize the funds. Without privacy, those who hold the monopoly on force can control and dictate the actions of others—at least, when the targets are limited enough in scope that the government can afford to do so.

Physical cash is anonymous but is not a great tool for the new world, where people want to transfer large sums of money across oceans quickly and repeatedly. Bitcoin is decentralized, but Edward Snowden aptly described it as “Twitter for your bank account.” Every transaction is visible to the entire network. If I buy a cup of coffee with Bitcoin, the barista can figure out my salary and other transactions I’ve made.

We need a digital alternative that is both private and decentralized to protect people’s sovereignty.

To address Bitcoin’s privacy issues, developers turned to the concept of zero-knowledge proofs—a method of proving the validity of information without revealing the information itself. First introduced in 1985, this technology could theoretically encrypt blockchain transactions while ensuring they remain verifiable. However, implementing zero-knowledge proofs efficiently was a significant challenge until 2013, when a team of scientists developed “Zerocash,” a method to make zero-knowledge proofs fast enough for practical use. This innovation laid the foundation for Zcash, launched in 2016 as the first cryptocurrency to implement zero-knowledge proofs.

Zcash also has a blockchain that records and publicly broadcasts every transaction ever made with it, but it hides all identifying information about who made the transactions and how much was spent. So, it provides decentralization akin to Bitcoin and privacy akin to cash.

Zcash combines the best features of both the old and new worlds. It is the true internet of money. With Zcash, you can make transactions without relying on profit-driven companies like credit card firms or exposing your personal data on public blockchains like Bitcoin. And this is just the beginning. Unstoppable private money that scales has the potential to become the engine of global prosperity, sparking a transformation even greater than the shift from barter to currency and fueling exponential growth.

Resources to learn more

• What are zero-knowledge proofs? - Z.Cash

• How is Zcash different than Bitcoin? - Z.Cash

Patron Saints of Zcash

• @zooko

• @nate_zec

• @aquietinvestor

• @ebfull

• @nuttycom

• @jswihart

• @Zerodartz

• @In4Crypto

• @zksquirrel

• @michae2xl

• @roommatemusing

• @zechub

• @zcashmedia

• @cameron

• @tyler

• You?

Thanks to Logan Chipkin for reading and giving feedback on drafts of this.