66

Here's a mathematical explanation: Calculate the number of blocks per 4 year cycle: 6 blocks per hour * 24 hours per day * 365 days per year * 4 years per cycle = 210,240 ~= 210,000 Sum all the block reward sizes: 50 + 25 + 12.5 + 6.25 + 3.125 + ... = 100 Multiply the two: 210,000 * 100 = 21 million. Economically, because the currency is effectively ...


22

There will definitely be a tragedy of the commons problem if things stand as they are now. This was discussed at some length here and elsewhere. There are some proposed ways to address this and make transaction fees nonzero (block size limit, hardcoded fees, insurance entities, mining cartel, gentleman's agreements which are maintained for fear defection ...


22

I don't know if this was thought up ahead of time, but it sure makes sense in hindsight. The reason 21 million is the right number is because people don't know how to value currencies. For instance, right now a Euro is worth $1.30 USD and a Japanese yen is worth about a U.S. penny. Ask someone which currency they would rather hold right now and most will ...


21

Wikipedia (Gold): A total of 174,100 tonnes of gold have been mined in human history, according to GFMS as of 2012.2 This is roughly equivalent to 5.6 billion troy ounces or, in terms of volume, about 9261 m3, or a cube 21.0 m on a side. Since Bitcoin is often compared to gold, total number of bitcoins matches total amount of gold mined in human ...


19

Mike Hearn just posted about how Network Assured Contracts handle this problem. I don't find an immediate flaw with this. This is how I understand the proposed solution: Anyone with an interest in a high hash rate (basically, anyone holding a large amount of coins), can initiate or cooperate on SIGHASH_ANYONECANPAY transactions. Those are an ...


16

No, you can't prevent fractional reserve banking technically. For example, IOUs can circulate just like Bitcoins and there's no technical means to stop it. Essentially, anything worth X Bitcoins (once risk and the like are factored in) can act just like X Bitcoins, even if it's not X Bitcoins. And since it's not Bitcoins, nothing Bitcoins can do can stop it. ...


15

Bitcoin is really a little strange because it doesn't know if it is a currency or a commodity. And this is why this question has many answers and is a popular item of discussion. If Bitcoin were just a commodity, the thing to do is to hoard it. There are lots of commodities that are almost totally hoarded. For example: emeralds or works of art. Now if ...


14

A non-malicious reason to deliberately destroy notable amounts of Bitcoins would be for a hypothetical alternative blockchain that recognizes Bitcoins sent to a special address as newly generated coins. One could for example try to establish a new "Altcoin" which is incompatible to Bitcoin, but every private key that signs a Bitcoin transaction to a special ...


14

The exchange rate at any one point in time is determined by supply and demand at the markets. The value of all bitcoins at the current market price is $80 million because the current market price is the point where the demand for bitcoins at a certain price meets the supply. You are describing introducing an artificial demand that would indeed cause ...


12

Some possible reasons I read: Merchant adoption through payment processors While merchant adoption is growing, it is currently mostly through payment processors, hardly any merchants keep a significant portion of their bitcoin earnings. With the broader selection of things to spend bitcoins on, more people are shopping with bitcoins, yet, not necessarily ...


11

Satoshi created a system that: Allowed users to trust transactions without having to trust any single entity. Opened it up so that anyone could participate and exchange computation power for Bitcoins. Is designing with a fixed size (21 million Bitcoins), he created an incentive for users to get involved early while Bitcoins are relatively cheap to generate; ...


10

With my only knowledge of the concept of "antifragile" being the slideshow I just read, my initial assessment is yes, Bitcoin is antifragile. Antifragile benefits from randomness and gains from disorder. Randomness in Bitcoin appears in the random generation of keys and in the whims of its users' spending habits. No one person controls the system, and a ...


10

the protocol allows a miner when he creates a block to send himself 25 BTC which do not have a proper source (input). that's how those 25 BTC are created, they're bitcoins that come from nowhere.


9

Certain escrow techniques rely on one party being able to "destroy" these bitcoins, without being able to steal them. For example I could put 10 bitcoins in escrow, giving a second person the ability to destroy them. Now if that second party lends me, say, 5 bitcoins, I can't simply run away from my debts without incurring a loss larger then the debt itself, ...


9

You could explain the coin limit like this: When Bitcoin started, its creator set a rule - "No more than 21 million Bitcoins will ever be created, and they will be given out gradually for creating blocks" (Add further explanation of block reward or proof-of-work here if needed). Everyone who joined Bitcoin knew about this rule, and they were all for it. As ...


9

The exact number of Bitcoins is not important. Whether the end result is 1 million or 100 billion makes little real difference. The important aspect here is the process, not the quantity. New Bitcoins enter the system in an orderly, predicable way. Outside forces cannot arbitrarily flood the currency with new money. An incentive is provided for people ...


8

I've read some of the linked discussions, and it seems some of the participants fail to understand the basic economic theory of the marginal cost. In any high fixed-capital business, the net present value (NPV) determines the ROI (IRR) and determines the opportunity cost where investors apply their capital. Thus, in normal functioning markets, the lowest ...


8

The process of attempting to buy all of the currency would drive the price up arbitrarily high. For example, I have some bitcoins and plan to sell 10% of what I have left every time the price doubles. I will never run out of bitcoins to sell, no matter how high the price, so it is impossible for anybody to buy them all. The US government could try to ...


8

The main issue with Bitcoin is not attracting late developers, but early developers. At its infancy, Bitcoin was an interesting curiosity - people would play around with it but not necessarily use it as money. But due to its scarcity and many benefits, Bitcoin came to be recognised as a digital currency. At that point people could either wait and see if it ...


8

Are Bitcoin Days Destroyed a measure of hoarding? Sometimes. But just because bitcoins changed addresses doesn't mean they changed hands. Is it also possible to derive velocity of bitcoin (money) from bitcoin days destroyed? Not directly. Although velocity of money and BDD are related, they are not entirely the same. velocity of money is based on a ...


7

Neither. The client chooses the best fit of coins for your spending. This is known as the knapsack problem. The coins chosen will be the ones that yield the lowest amount of change, with exceptions for very recent (unconfirmed or newly confirmed) coins. Even when there are multiple solutions that yield the same amount of change, it will not necessarily ...


7

Idealists might argue that Bitcoin was developed to forever change the financial landscape, and would be affronted at the suggestion that Satoshi was out for profit. Skeptics might call the whole thing the most elaborate Ponzi scheme ever envisioned. Realists might suggest that Satoshi, emotionally traumatized by the recent unceremonious departure of his ...


7

Here's the page on the wiki where weaknesses are addressed.


7

The upper boundary for energy usage can be described with a function of the profit and energy costs. Miners won't ever pay more for energy than they get from profits. The actual energy usage formula will also have to count for the hardware costs. The formula will look something like this : max energy usage = (profit - hardware costs) / energy cost per unit ...


6

I don't know if any of this data is of any use or significance, but... I calculated the Gini coefficient at the end of each month of Bitcoin's history. I did it in two different ways: The vast majority of Bitcoin addresses that have ever been used are now empty. They don't represent the "have nots", they're just addresses that have been used and ...


6

There are huge differences between FIAT and Bitcoin. Fiat is created out of thin air "with fractional reserve banking" and other mechanisms, there is no stop on how many will be created. Another problem is that every country is FORCED to create more of it. Since otherwise the value of their money would increase to much, ending all export industry and ...


6

Assuming blocks are solved at the targeted rate of one block every six minutes going forward from today, the date the block block reward subsidy drop will occur happens in late November. http://www.BitcoinClock.com Currently the target rate is 7,200 BTC per day. Starting with block 210,000, this will drop to a targeted rate of 3,600 BTC per day. This ...


6

There are many causes for inflation, but the two most often agreed upon, according to Investopedia, are these: Demand-Pull Inflation - This theory can be summarized as "too much money chasing too few goods". In other words, if demand is growing faster than supply, prices will increase. This usually occurs in growing economies. Cost-Push ...


6

There were only about 2 million Bitcoins mined when the system was fully announced and opened to the public. They are owned by Satoshi and other early adopters. While they have a huge present value, that's because their value increased. Long after the Bitcoin system was public, Bitcoins dropped down to $2. At that time, the value of the early adopters ...


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