# Creating a living currency

I'd like to implement a currency that is "alive".

Picture a small, rat-sized animal that is:

• only found in a small geographic region, making it reasonably scarce.
• lethargic, or in hibernation most of the time, unless to fly/burrow away from predators.
• derives energy automagically through exposure to the sun or other celestial body.
• has surface composition such that it is prohibitive, but not impossible, to counterfeit.
• is scratch- and heat-resistant.
• reproduces asexually at a slow, constant rate.

My initial references were something like Crystal Lizards from Dark Souls.

Knowing that

"Anything can serve as a currency and ultimately the winners will possess the characteristics that people demand: portable, fungible, easily divisible, and reasonably scarce" - John Matonis

Assuming a technology level no later than 19th century, does the fact that it is not easily divisible and not necessarily fungible preclude it from being used as a currency?

• Is the animal used as currency alive, or dead? It can be divisible on the latter state... ; – adonies Jun 6 '17 at 19:34
• Anything can be a currency if people believe it has value, take bitcoin for example which is only 0's and 1's but they are worth thousands – Ben Poulter Jun 6 '17 at 19:40
• Fun fact: in the medieval times squirrel skins/furs ("oravannahka") were used as currency in Finland. According to linguists, the current Finnish word for money, raha, directly derives from some old word that stood for squirrel skin/fur. A cow would be worth about 100 squirrel skins, and a good hunter could catch between 10-15 squirrels a day. – ZeroOne Jun 6 '17 at 20:26
• Animal-related words evolving into money-related words is not uncommon: etymonline.com/index.php?term=pecuniary. – chepner Jun 7 '17 at 0:34
• "derives energy automagically through exposure to the sun or other celestial body" makes it a plant, not an animal... – L.Dutch Jun 7 '17 at 10:12

Could it be used as a currency? Possibly. It is reasonably valuable and durable. There are some issues:

## Inflation

Depending on how slow they reproduce, and how long they live, you could just get a bunch of "money" and leave it alone in the back closet for a while and it would breed new money. You don't even have to feed it. This means, concentrated efforts over time will eventually make the currency worthless, as every available dollar rat would be bred as often as possible (and I'm sure plenty of research will go into making them breed more often). This, naturally, leads to inflation.

## Portability

This ties in with Inflation and Value. Basically, you need to be able to easily transport enough money to buy what you need. A small, rat-sized object might be fine if that can buy something of value, but since you can't "break" a rat into change, that's a problem. Now one small rat is the base unit of currency. Imagine a world where 100 dollars was the smallest unit of currency. If you had to spend 100 dollars every time you bought anything, it'd be a nightmare (one eventually solved by the other side of the problem: low value).

If rats were worth next to nothing, say \$1 each, now you need to bring a lot of rats to pay for anything. This is the exact opposite of the too valuable rat problem.

## Value

I touched this in the portability issue, because they are related. Basically a rat, as the base unit of currency, needs to be able to represent the smallest transaction. Since it cannot be divided, you have to spend "whole rats" to buy anything. A rat being too pricey relative the costs of goods makes buying things hard. A rat being too cheap relative the cost of goods makes buying things annoying.

## Conclusion

Rats could conceivably be used in trade, but I doubt they'd be a unit of currency. There are so many other things that could be used that are better stores of value, are more divisible, and easier to manage.

• Specific traits could value the rats. If it has red eye, it worths 100 brown-eyed rat, if it has two tails, it worths 1000,000. The weird, asexual, magical genetics of the rats could ensure that these traits remain rare, and their latency does not change. – b.Lorenz Jun 6 '17 at 19:40
• Still has the issue of the base unit of currency being a small rat. Plus it would be very easy to counterfeit things like eye color – Marshall Tigerus Jun 6 '17 at 19:42
• Not so easy. Mind, pre 19. century technology. But maybe red eye is not the best example. – b.Lorenz Jun 6 '17 at 19:48
• @nuclearwalrusnetwork You probably didn't use enough fertilizer. I find quarters work best. I fertilized a buried penny with a roll of quarters once... a few years later, when I checked on it, I found a root structure worth almost 9 bucks. I'm still waiting on it blossom above-ground, but it's a solid start. – HopelessN00b Jun 7 '17 at 22:41
• If the money isnt immortal, then inflation could easily be balanced out. I actually would worry more about deflation. "I fell on my pack and killed all my money" would be a common occurrence, and so they would have to reproduce fast enough to counter it. In the current world countries always want a little bit of inflation as it makes it more valuable to invest money rather than store it. – theinvisibleduck Jun 8 '17 at 19:32

I think the problematic word is "currency". If that word were changed to "investment" then you could easily have a situation like the Dutch Tulip Mania that occurred in the 1600s. An investor class awash in money and looking for unexploited niches to return fast cash could create a bubble out of almost anything (for a while), even living things like flower bulbs.

But currency alone doesn't actually have value. It's just paper that we agree has a value. We use it for convenience, but it evolved as a receipt for a commodity. In ancient times that was grain in storage, but later it was a banknote serving as a receipt for a bank account. Currency isn't the thing of value, it's the convenient token you carry that represents the value.

Your "bitcoin rat" would have actual value. Its scarcity and steady reproduction would guarantee inflation. It's durability and un-counterfietability would make them very reliable longterm investments. The very wealthy might have rats to spend, but the average middle class shopkeeper would still use paper and coin currency.

• +1 for "bitcoin rat", anyway I think that if they had some intrinsic value (as ex. magic component) then they would not only be technically possible, but actually even reasonable. – Shadow1024 Jun 7 '17 at 11:19
• I would change that word again... not currency or investment, but rather that which you mention later: commodity. In effect these rats would be Commodity Money. – MichaelK Jun 8 '17 at 9:35
• +1 for Dutch Tulip Mania. One of the fun examples of how crazy we humans are. – Marshall Tigerus Jun 9 '17 at 13:29

Assuming a technology level no later than 19th century, does the fact that it is not easily divisible and not necessarily fungible preclude it from being used as a currency?

No, it does not prohibit it, but it makes it extremely unlikely. For one, it is easily divisible; the same way gold was: A "bank" that has many rats can issue a promissory note in rat fractions that becomes money. They can also have something difficult to reproduce or fake on their promissory notes; much like our own money: Special paper, ink, and an extremely intricate design hard to reproduce particularly with late 19th century technology. Remember, our own early money IRL was a promissory note redeemable in silver or gold. Your is just redeemable in Rat! But it takes (for example) 100 single notes to actually get a Rat. For lesser denominations, they are still good for trade: The baker knows that he needs to sell 100 loaves to get a hundred singles, but at the Bank he really could trade those 100 singles for an actual Rat. If he wants. But he might prefer to let the Bank take any risk of accidental Rat death, and just keep the stack of promissory notes that are just as exchangeable. It is safer.

This is the flaw in your system, I think. It will be replaced by promissory notes almost immediately.

It is a misconception to think Scarcity is important for a currency. It is not exactly so. Money must be difficult to forge, and difficult to just find lying around in nature.

The scarcity of gold and silver just meant it was hard to fake, and hard to just go on a hike and get some. In real life, our currencies are hard to fake, but are not themselves made of anything scarce. And they don't just occur in nature, so it is hard to just hike in the woods and find some growing on a tree.

But that said, not everything scarce and hard to find makes a suitable currency: Consider Truffles. They can be extremely expensive, they can't be faked, they are hard to find, but they are an unlikely currency.

The defining characteristic of currency is widespread trust that it can be exchanged for equal value of goods, labor or services. Now "equal value" is nebulously defined, a fuzzy definition. Still we know what it means; that if a guy gets paid 100 singles for a day of labor, he knows what else he can buy for that 100 singles, in food, in entertainment, in tools or travel or transportation. He trusts that the five Twenties he was given are going to be accepted in trade for almost anything he wants to buy. The money does not have to be backed by anything as long as effectively everybody believes it will be accepted in trade; that is why vendors take it, and workers accept it as pay.

So the biggest concern about money is forgery and theft. If your Rats are very difficult to forge and not easy to find ; and no easier to steal than modern currency, then they can be a basis. But like Gold and Silver, IRL, they would likely be replaced by promissory notes, and then just replaced by hard-to-counterfeit paper products.

Added: This occurred to me later: You provide the perfect reason that Banks for rats would arise, how it is in their self-interest and why people would use them (in their self-interest): The rats sometimes reproduce. So the bank, in return for ensuring the life of your Rat (the promissory notes they give you, upon deposit, are redeemable for any Rat, not just your own), also keep any new Rats your rat may produce. Instead of our massive vaults for holding Gold and money, they have massive guarded rat gardens; with the rats in trays, perfectly sunned, watered, cooled or shaded, provided medical care as needed to optimize reproduction: That is their profit; it minimizes rat death and rewards them for being custodians of the rats. Like our own first banks, they can "loan" rats, by producing promissory notes collateralized by real property; e.g. a mortgage on your farmland so you can purchase animals, equipment and seed to farm it. Interest bearing loans, of course. People use the banks because they provide free (or low cost) life insurance on their rats, in return for the rights to offspring. Like life insurance, it is better to give up the rare lucky chance of offspring, to be protected against the unlucky chance of losing a rat in an accident, fire or assault.

• It will be replaced by promissory notes almost immediately. If the author wishes to avoid this occurrence, they could introduce some general mistrust of banks, whether well founded or not. If people are afraid that a bank is going to go broke and all their wildcat currency will become useless, they'll sooner stash their rats safely in their mattresses than put faith in paper IOUs from smooth-talking usurers. – Thriggle Jun 8 '17 at 20:28
• @Thriggle A bit of a transparent deus ex machina; for such an otherwise useful function; I think. Transparent because the only purpose of such an irrational fear is to perpetuate the living currency conceit of this story. But if it happens, at least we will have done our part in helping to make this story seem a little less contrived. – Amadeus Jun 8 '17 at 21:36
• The 19th century was when the Panic of 1837 occurred, so bank mistrust in an analogous timeframe would not be too artificial given similar circumstances, but you're right... it certainly didn't stop the use of paper money in our timeline! – Thriggle Jun 8 '17 at 22:04

Shells.

In China, cowries were so important that many characters relating to money or trade contain the character for cowry: 貝. Starting over three thousand years ago, cowry shells, or copies of the shells, were used as Chinese currency.[2] The Classical Chinese character for "money/currency", 貝, originated as a pictograph of a cowrie shell.[3]

Your lethargic, unusually-surfaced, scratch resistant creatures are like shell money in all respects except for the energetic automagic. It is not immediately obvious how a creature like the cowrie does get its nutrition; exposure to the water instead of exposure to the sun.

I am not sure if you meant for the creatures to stay alive while they were used as money - probably you did. Live cowries were not used because the organism would die, then stink. But suppose cowries were more robust and durable. Would cowries be less suitable as money if they could survive alive in your drawer / purse / treasure chest? Sure - why not?

That said I would hesitate to use my front pocket to keep something that can burrow.

I don't see why not. We have historical records of cows and horses being used as the basis for a barter economy. It also has some amusing possibilities for a get rich scheme where someone discovers growth hormones.......

• Oh, yes. That's quite true. To nomadic herding people, livestock is traditionally how wealth was measured. – T.E.D. Jun 6 '17 at 19:50
• All livestock had trade/barter value because they had intrinsic value of their own as livestock. Rats have no such - they're proposed to be used as tokens instead of coins, in representation of value in some (undefined) bank system. So I think your answer doesn't stand. – adonies Jun 6 '17 at 19:57
• My cat thoroughly disagrees with you. – steverino Jun 6 '17 at 20:04
• @steverino because it's looking forward to your using rats as currency. – adonies Jun 6 '17 at 20:19
• there is a difference between a valuable trade good and a currency. – John Jun 8 '17 at 21:07

Hibernating Beetles

Your currency is not a rat, but a species of incredibly rare beetle. So rare that there is only one queen beetle left, which is firmly under control of the Department of Treasury. These beetles are roughly the size of a coin, and when taken far enough away from the hive mind of the queen and colony, enter a state of hibernation wherein they are not dead, but are simply dormant, and can remain that way more or less indefinitely if kept away from the hive mind. In addition, these beetles have several different morphs in the style of snakes, with each morph having unique coloration and being relatively consistent in the percentage of each generation which will have that coloration, providing you with different denominations for your currency. Obviously the queen beetle is kept in an underground bunker, thoroughly guarded and buried so deeply that even someone walking directly above does not have their beetle purse come alive and trying to burrow through their pants.

• This would be an interesting RPG event, hard, golden coloured, coin shaped bugs, they appear in a nearby treasure mound, heroes bring them to the surface, the locals start using them as currency, demand increases so others go back to collect more, the queen wakes one cycle to notice 9/10th of her hive is gone. She follows the trail. As soon as she gets close to the town, the coins "come alive" Mummy style, and eat all the towns-people, she then burrows down below the town for the next cycle. – BaneStar007 Jun 8 '17 at 23:40
• @BaneStar007, that would be great. The party hears one day that a town they had recently been to and spent a considerable amount of money at had been mysteriously decimated, every corpse reduced to nothing but bones, and small holes dotting the ground. The party returns to the town to investigate, only to find their own coin purses coming alive. – Cameron Jun 9 '17 at 13:01
• @BaneStar007 I'm stealing that idea for my next D&D game. – Marshall Tigerus Jul 7 '17 at 17:45

I dont think any living creature could realistically be used as currency.

Any living thing needs to reproduce, so reproduction alone would cause runaway inflation. Death is always uncontrollable, you wouldnt want to be paid in creatures that suddenly die the next day. You wouldnt want to have to pay to feed your money to keep it alive. Its simply unrealistic any society would adopt such a high maintenance currency.

This being said living organisms have been used as trade goods throughout human history. Slaves as one example. As long as the organism fulfills a role people will pay for it, or be willing to trade it for something else.

• Please read the question thoroughly, it was stated that it "derives energy automagically through exposure to the sun or other celestial body." – Cameron Leary Jun 6 '17 at 21:03
• True, but what happens when left in a dark place like a home or vault cut off from their energy source? And @Reproduction if they are reproducing anywhere other than a controlled provider (like a treasury) then it becomes runaway inflation. Ultimately my point is, using a living thing as a currency in place of low maintenance static objects, becomes infeasible, not worth the time for a civilization to implement. – anon Jun 6 '17 at 21:58
• Sheep, goats, cows and camels are perfectly good currency in a suitable economy and have often been used as such. – Separatrix Jun 7 '17 at 8:13
• Frankly, +1 for pointing out that patience will cultivate wealth without the involvement of any other party. I wish I could give you +2 for pointing out that dying critters means no stuffing of mattresses. It almost mandates a cottage industry (let's call it a "bank") supplying currency husbandry ("We guarantee to replace your dead rat with a new, live one!") – JBH Aug 28 '18 at 0:34

Cattle has been used as currency, means of exchange and wealth store.

Horses in Mongolia, camels in deserts, cows in America, goats, sheep, etc.

The upside is portability (they can be driven en masse), inherent value (can be butchered / milked / shorn / worked), and protection from inflation (they reproduce, but slowly, require a lot of food to grow; reproduction is offset by disease).

However, when you get to 19th century society, your currency is likely to change to account for amount of money available (i.e. trust). A natural transition is to skins or pelts (middle ages to 16th century), and from then on to something more... malleable, like promissory notes.

In summary, rats are fine early on, but not in 19th century.

A couple points: First to answer your question, I believe your "currency" is fungible. I further believe divisibility is a problem and I don't think it is a viable currency. But you have bigger problems.

Your currency does not hold value. Your beings will lose their value by dying or by flying off or burrowing. I would see it as a great risk to have to place my money in the sun to prevent it from dying. Besides, no creature on earth is free from predators.

Further, I would contend that I would prefer not to carry more than 5 rat sized things at a time for any distance to pay a person for a loaf of bread. There is also the chance of dropping one and waking it up and it escaping. You also cannot hide that you are or how much money you are carrying making you especially vulnerable to robbers.

And finally, if anyone finds out the geographic location this scarce (endangered) animal can be collected, its habitat will be devastated is a short time and there will be no more.

BTW, I giggled a little because I imagined this asexual reproduction would not be spontaneous and at some point, when one was about to become two, the value would double. Unless there were complications at birth and you lose both... such risk. Lets go back to trading shiny rocks.

Yes, but:

While Living Beings have been used as trade-able currency, They also produce goods or are goods in their own right, milk, wool, meat, transport.

Currency that does nothing, other than be currency, are so because they have perceived wealth. But originally, they also had an ability: Gold/Silver could be made into jewelry, so large wealth could carried on your person.

So for your rat-coin to be worthy of the title currency in the pre-promissory note world, it would need this 'value' too.

You say it derives energy without physical need, can that energy be transferred partly to the owner? If I carry 5 of them, can I skip lunch? 15 of them, no food required? Or can mages tap into that energy for spells?

If you added worth to the rat (why would I ever want a rat in my pocket - eww) then yes, it could become a 'tradable' currency.

Inherent vs Backed Value

Most currencies either have inherent value (gold, livestock) or value backed by a government agency. In both cases it's a matter of perception that grants the currency its purchasing power.

Currencies that rely on their inherent value, provide a direct benefit or utility to an individual. Take the example of livestock, which can provide food, labor in the fields, or a means of transportation. Gold or other precious metals are sought out for their chemical, physical or aesthetic properties. In Frank Herbert's Dune a special spice is considered a currency for granting its users psychic powers required for space travel. When a substance, object, or phenomenon grants utility that is fundamental for the vast majority of individuals of a society, then it can easily be integrated as a form of currency.

Luxury goods that are only desired by a small fraction of a society will struggle to be accepted as a currency, unless the target group provides some other function that supports the whole of the society. Example: Mages that provide nation wide transportation and who seek out special crystals that others find useless. Such crystals might become currency for the entire society.

In contrast, backed currencies rely on an agency with government-like authority within a society to stabilize and standardize its use. Often such currencies are linked to other goods or limited resources that do have inherent value (e.g. originally USD and gold), which helps build trust in the currency in its earlier stages. Currencies work because members of the society perceive them as having value and are willing to exchange their present goods and services for the reassurance that said currency will allow them to acquire future goods and service when needed.

When a currency functions appropriately each individual will agree for the most part with the value attributed to such a currency (give or take). However, if enough people lose faith in a backed currency or disagree on the inherent value of a currency, then trade is burdened and devaluation or hyper-inflation of the currency may occur.

Creating a fictional currency

For your rat-based currency to be believable, you must find either a way for them to have inherent value (e.g. medicinal properties or production of some byproduct) or find adequate reason why society would have decided to use the rats as a backed value. What properties must they have that makes them functionally better than alternatives to be a backed value. Scarcity of paper and metals to mint and print other currency and the lack of digital technology, might be one way to approach the problem.

Issues with divisibility, transportation, and functionality of a currency are moot as long as the perceived value within the currency is apparent. Past societies have managed to get around clunkier means of trading using cumbersome currencies to haggle with.

Forging or in the rat's case breeding more currency could easily be avoided by adding some biological caveat. Some ways to address this would either be having the ruling faction or government be the sole owner of the female rat(s) and only male offspring being spread across the society. Another way is to limit the procreation means of said rats making it difficult to breed them.

Genetic-algorithm infused cryptocurrencies. I would mark it as Sci-Fi, but it's actually happening today, so maybe you're looking for a more fictional and less realistic answer.

• only found in in virtual space, making it relatively inaccessible to those without necessary infrastructure

• lethargic, or in hibernation most of the time, mutations occur at a slow rate so as to allow AB testing via a test user base, imagine Alpha, Beta versions tested and implemented on mainstream after confirmed benefits

• derives energy from miners aka people devoting their processing power to the betterment of the self-improving alhorithm
• has hashed cryptography, making it incredibly difficult, but not impossible, to counterfeit / hack
• is resistant to anything barring a fallout of electrical technology. reproduces asexually at a slow, constant, predetermined rate, impossible to change. bonus: this rate can be self-adjusting to maintain optimal availability and inflation. alternative: can be capped at a fixed rate (like bitcoin), making it a deflationary currency, making it thus an investment asset as well as a currency.

It's a bit difficult to get in the technical aspects of how the genetic algorithm works, but i'll give it a quick shot via this link:

1. The algorithm begins by creating a random initial population.
2. The algorithm then creates a sequence of new populations. At each step, the algorithm uses the individuals in the current generation to create the next population. To create the new population, the algorithm performs the following steps:
• Scores each member of the current population by computing its fitness value.
• Scales the raw fitness scores to convert them into a more usable range of values.
• Selects members, called parents, based on their fitness.
• Some of the individuals in the current population that have lower fitness are chosen as elite. These elite individuals are passed to the next population. Produces children from the parents.
• Children are produced either by making random changes to a single parent—mutation—or by combining the vector entries of a pair of parents—crossover.
3. Replaces the current population with the children to form the next generation. The algorithm stops when one of the stopping criteria is met

Basically a currency which self-evolves by assessing the needs of the economy.

For example it could discover bugs and exploits faster than humans could, and fix them before giving anyone a chance to take advantage of it.

In addition to it being a blockchain, which would essentially make it a public (but hashed, i.e. encrypted) distributed ledger wherein every single transaction (bonus: and mutation) is recorded in the metadata of the currency itself.

Imagine having a dollar note which has its entire history attached to it, along with key metrics e.g. Money Supply, Inflation, Velocity, etc. printed on it.

Pretty neat.

EDIT:

"Assuming a technology level no later than 19th century, does the fact that it is not easily divisible and not necessarily fungible preclude it from being used as a currency?"

Admittedly, I skipped over this part, because there are already great answers pertaining to that specific criterion. However, I'm using a definition of "alive" meant to challenge typical assumptions. The OP takes it extremely literally (an actual living rat), but a self-acting agent such as the one described above is by most means alive. Only it was discovered 1 century later than specified.

• can you flesh out this answer a bit more? – L.Dutch Jun 8 '17 at 9:45

Not as currency

The real problem is size, you can't carry enough rats for workable transactions.

Imagine if every bill in your wallet was the dimensions of a can of soda, now imagine trying to carry decent amount of currency, 20-30 bills of various value. You will need a backpack for a wallet. It's just too cumbersome people will switch to something else very quickly. If you can't fit half a dozen of them in your hand they will not make for good currency.

your rats may be valuable trade goods, they may even be the base value your currency is based on, but as physical currency they are useless.

Picture a small, rat-sized animal

That's not small enough. Think size and weight of coin. A rat is like a large bag of coins.

Which makes them either very valuable (too heavy/bulky to carry many), and so not suitable for normal transactions, or requires them to be of low value and forces everyone to carry a lot of them. This is pointless for a currency.

only found in a small geographic region, making it reasonably scarce.

So in effect the entire world's ability to produce money can be either wiped out by a culling or a bad winter or a virus, or the region can be taken over by force.

That's not a currency, it's a war zone waiting to happen.

lethargic, or in hibernation most of the time, unless to fly/burrow away from predators.

A solar powered creature that burrows ? No.

And a hibernating solar powered creature is even worse.

derives energy automagically through exposure to the sun or other celestial body.

This isn't possible in my view as even if they could somehow generate enough energy to live doing this, they could not grow as growth requires food for raw materials and a digestive system to deal with it. No growth means no way to develop from infant to adult.

And of course if you need to feed your creature, because you can't have a solar powered one, then just having money will cost you money.

has surface composition such that it is prohibitive, but not impossible, to counterfeit.

I don't see how you could counterfeit a living currency. We can't counterfeit a rat in a laboratory now.

is scratch- and heat-resistant.

Everything has some level of scratch and heat resistance. But compared to a simple metal coin, these things won't be durable.

If they have a scratch resistant shell or skin, you'd discard the body and use the skin as a currency. Why would you carry around the live creature at all, when the skin is what's useful ?

reproduces asexually at a slow, constant rate.

Which makes spending them a very poor way to use your money ! These would inevitably be hoarded.

This is not possible anyway with a solar powered rat as it's is prevented by the same issue as my "growth" argument above.

The fact that just leaving them in a heap will produce more of them means that, in effect, the money has a built-in devaluation effect. This is just disastrous for an economy. More of them being "born" is equivalent to printing more paper money - you haven't really made more assets to back the currency, so the currency's value must decrease.

does the fact that it is not easily divisible and not necessarily fungible preclude it from being used as a currency?

As I've explained, that's the least of the problems.