The definition of money, like most foundational ideas in economics, has not changed much since William Stanley Jevons codified it in 1875. The six characteristics of money —durability, portability, divisibility, uniformity, limited supply, and acceptability— have served as the standard ever since, a framework so durable that it survived the shift from gold to paper, from paper to plastic, and from plastic to the first generation of digital payments without requiring meaningful revision. What has changed, or shifted, is the range of assets those characteristics can now be applied to. When Satoshi Nakamoto mined Bitcoin's genesis block in 2009, embedding in its code a headline about the fragility of the banking system he was building an alternative to, it marked the first serious challenge to a definition that had gone uncontested for over a century. 

 

For the first decade, that challenge was largely philosophical. Today, it is structural, and the six characteristics that Jevons defined are being stress-tested by assets he could never have imagined. 

 

The six characteristics of money

 

Durability

 

The original concern was physical. Gold doesn't rust. Paper money deteriorates. Commodity currencies spoil. For most of monetary history, durability was a question of whether the medium of exchange could survive long enough to be used again. Digital infrastructure movies the question away from the physical properties of a medium and toward the systemic robustness of the network that carries it. Well-established blockchain networks have demonstrated a form of durability that many traditional financial systems, built on aging technology and single points of failure, struggle to match. In a digital context, durability is no longer a constraint. It is a baseline.

 

Portability

 

For centuries, portability meant how easily you could carry value across physical space. For Gold and cash that principle is easily applied. Wire transfers can also be moved, but have been slow, expensive, and dependent on correspondent banking relationships. Consider how portable a wire transfer actually is. Sending money across borders can take several days, involves multiple financial institutions, and extracts fees at every touchpoint. But move the same value in stablecoins and the transaction settles in minutes, globally, at a fraction of the cost. Value that once required institutional mediation to move can now travel as freely as an email. 

 

Divisibility

 

Traditional money divides well. Most real-world assets do not. You cannot spend a third of a share, transact in fractional real estate, or deploy a partial bond position to make a payment. The indivisibility of assets has always been one of the primary reasons they don't function as money, even when they hold significant value. But when an asset exists on a blockchain, it can be divided to whatever granularity the protocol allows. A far-reaching principle as it removes the barrier that has historically kept entire asset classes out of the monetary conversation. Thanks to the blockchain, fractional ownership of real estate, equities and commodities is possible. An asset once too coarse to function as a medium of exchange can, once tokenized, transact in increments smaller than a cent.

 

Uniformity

 

For money to work, each unit must be interchangeable with every other. A dollar is a dollar regardless of which bill it's printed on. In a similar vein, each token representing a share in a money market fund is, by the logic of the blockchain that records it, identical to every other token in that same fund; a form of enforced uniformity that physical assets, with their variations in condition, provenance, and authenticity, have never been able to guarantee. Within a given tokenized system, uniformity is an architectural property.

 

Limited supply

 

Scarcity has always been a foundational principle to monetary value. Currencies inflate when supply is unconstrained, and Gold held its value in part because producing more of it was genuinely difficult. But to pose an example of digital assets, unlike fiat, Bitcoin's supply is fixed at 21 million by the mathematics embedded in its very protocol, making it immutable and publicly verifiable by anyone at any time. For the first time, scarcity was programmed rather than simply promised. The market is already sorting the credible assets with transparent, verifiable supply constraints that are attracting institutional capital, from those without, which face the fate of every currency that has ever been inflated into irrelevance.

 

Acceptability

 

This has always been the hardest characteristic to engineer and the easiest to lose. A currency is only money if people accept it, which is partly rational, partly social, and, fundamentally, backed by institutions. Today, digital assets are undoubtedly gaining acceptability, but the speed at which institutional infrastructure is being built around them is truly remarkable. Custody solutions, settlement rails, regulatory frameworks, and payment integrations are lowering the barrier to adoption for both retail and institutional participants. Stablecoins are already being used for cross-border payments, treasury operations, and everyday transactions in markets where traditional infrastructure is slow or inaccessible. Acceptability is not yet “universal”, but it is accelerating faster than most would have predicted even five years ago.

 

The seventh characteristic of money 

 

For the first time in monetary history, the six characteristics of money offer a framework that can be satisfied by a far broader range of assets. A tokenized equity, a stablecoin, a digitized dollar demonstrate durability, portability, divisibility, uniformity, limited supply, and acceptability in ways that would have been technically impossible a generation ago. But meeting the six characteristics individually is not, it turns out, sufficient. An asset can pass every one of Jevons' tests and still fail the most important one of all: the ability to move freely, convert instantly, and interact with other assets across the fragmented ecosystems that make up the modern financial system. That condition has no name in the 1875 textbook. Today, I call it interoperability. 

 

Interoperability is not necessarily a feature, but rather the precondition for everything to work as one. A tokenized asset that meets all six of Jevons' characteristics but cannot move freely between networks, jurisdictions, and use cases is technically trapped, limited. The six characteristics of money describe what an asset is, whereas interoperability determines what it can do. Take the internet, for example. It didn’t reshape the world because information became digital, it reshaped the world because common protocols allowed it to move freely across previously isolated systems. The value was therefore, not in digitization, but in its connectivity. 

 

Finance is approaching the same point. The tokenization race now underway across Wall Street is the digitization phase. What comes next is connectivity, and with it, infrastructure capable of moving value freely across blockchains, asset classes, and settlement systems, collapsing the chain of liquidation, intermediaries, and settlement delays. Today, deploying an asset in a transaction still requires that chain, regardless of whether the underlying asset is tokenized. Interoperability removes it. Conversion happens at the point of transaction and the asset goes directly to the payment.

 

This is the problem ForumPay is built to solve: to build the payment rails that make asset class irrelevant. Whether it is Bitcoin, a digitized dollar, or a tokenized equity position, the infrastructure will handle the payment, transaction, conversion because it’s dealing with fungible value, not separate assets. The fabric that allows that to happen is connectivity. If the six characteristics of money tell us what money must be, interoperability is becoming the condition without which none of the others fully count.