Now, for those of you who aren’t techno-libertarians, Bitcoin is supposed to be a visual currency you can use to buy things online. Except it's not really a currency, and you can’t really buy that much with it. It’s more like a dotcom stock - circa 1999.

　　如今，不是技术自由主义者的人认为，比特币应是可以用于网上购物的虚拟货币。只是它并不是真正的货币，你也不能真正使用它来购买太多东西。比特币更像一支1999年前后的网络公司股票。

　　See, in just the last month, one Bitcoin has gone from closing at a then-record US$192 to reaching $788 on Monday. It then opened at $502 on Tuesday, before briefly rocketing up to $900, and ultimately falling to $646. Just your average 80 percent price swing. That’s totally normal for currencies, if you multiply their biggest swing by 80.

　　看，就在上个月，1比特币在周一从收盘时当时的最高点192美元升至788美元。周二开盘502美元，随后短暂地飙升至900美元，最后又跌到646美元。只有平均80%的价格波动。对货币来说，这是完全正常的，如果你把货币最大的波动幅度乘以80的话。

　　You can kind of see these absurd price moves in the chart. But only kind of, because the vertical up-and-downs have come so fast that they've blurred into each other. It’s almost as if Bitcoin doesn’t have a single price at any one time, but rather a range of possible prices that depend on the observer. We can see this a little better if we zoom in on just the last two months. Bitcoin prices were pretty flat from the end of September through early October, but then (relatively at least) doubled slowly. Then they doubled quickly. And then even quicker - before falling fast. Not exactly a stable store of value.

　　你可以通过图表略微了解这种荒唐的价格变化，但只是略微，因为垂直涨跌线的变化如此迅速，彼此已经重叠而模糊。看起来比特币似乎在任何时候都没有单一价格，而是一系列可能的价格，这取决于观察者。如果我们只放大观察过去两个月的情况，能更清楚地明白这一点。从9月底到10月初，比特币的价格相当平稳，但随后(至少比较)缓慢倍增，后来迅速倍增，再后来更快-进接着快速下跌。完全不是稳定的价值储存手段。

　　See, the idea behind Bitcoin is to create a decentralized currency that central banks can’t inflate and governments can’t tax. Basically, digital gold. And like actual gold, the only way to get new Bitcoins is to “mine” for them. That involves running a computationally-taxing programme on your computer that mostly generates gibberish, but maybe, just maybe, some Bitcoins, too. The key, though, is that mining for more of the virtual currency doesn’t create more of it. That’s because there’s a predetermined number of Bitcoins.

　　瞧，比特币背后的设想是创造一种分散化货币，各国央行不能让其升值，各国政府也不能对其征税。它基本上是一种电子黄金。与真正的黄金一样，获得新比特币的唯一方式是“开采"它们。这要求在你的电脑上运行一种计算繁杂的程序，该程序大多数情况下生成无意义的数据，但可能，只是可能，也同时生成一些比特币。然而，问题的关键是，开采出更多这种虚拟货币并不代表可以制造出更多比特币，这是因为比特币的数量是预先确定的。

　　Specifically, there are around 12 million today, and there will be 21 million in 2040 - and no more after that. Of course, this limited supply means Bitcoin should tend to increase in value against the dollar. But only tend to. See, its deflation means Bitcoin prices will go up and down quite violently.

　　具体地说，现在大约有120万比特币，20年将达到210万-此后不会再增加。当然，这种限量供应意味着比特币易于对美元升值。不过只是易于，其通缩趋势意味着比特价格会剧上涨或下跌。

　　Think about it this way. The supply of Bitcoins can’t increase much to meet increased demand, so increased demand will make prices soar. And soaring prices will make early adopters try to cash out their winnings - which will send prices crashing back down.

　　这样来理解比特币：比特币供应量无法增加太多，从而无法满足增加的需求，因此增加的需求会使其价格飙升。飙升的价格又会导致早期接受者试图将赢利套现，这样又会使价格狂跌回去。