A currency is an attributable symbol whose meaning is common – consistently accepted, acknowledged – within a group of people, and over time.
The commonality, commonplace of a symbol is what distinguish a currency from other symbols. Currency is etymologically what runs, what is everywhere, not necessarily because it measures a flow, but rather because its meaning is everywhere. I would argue that the existence of currency precedes in time the flow of wealth it may at some point trigger. I would also argue that a currency can but does not have to be formal, agreed upon, well-defined, it can be instead informal, emergent.
For a symbol to become currency requires either (or combination of):
- force: this is the easiest. someone forces onto others the meaning of the symbol, such as is the case of the Government legal tender laws and monetary policy.
- emergence: this is the most fascinating, because it is uncontrollable and can result in very quick social changes. An example is: having a Web site, blog, LinkedIn profile, twitter stream is a currency, if you don’t have one, it will raise strong doubts from a hiring manager.
- agreement: this is probably the hardest. A group of people decide together that something will be used as currency.
Clearly, understanding how a currency emerges, and designing for a symbol to emerge as a currency seems to me to be a potentially very powerful piece of knowledge that I feel isn’t much written about in the Internet literature.