比特幣從今年年初的單價不到1000美元，已經一路狂飆到了今天上午的11,800美元以上，已經鐵定成為有史以來升值最快的單一資產。在比特幣誕生初期，對區(qū)塊鏈技術缺乏了解的懷疑論者斷定，“比特幣熱”注定只是曇花一現。但隨著有關知識的普及和幣值不斷創(chuàng)下新高，懷疑論者的聲音也變得溫和了許多——不過就算你也是比特幣的擁躉，這些懷疑的聲音也是非常值得一聽的。

伴隨著比特幣的幣值繼續(xù)狂漲，有幾點看跌比特幣的理由也非常值得注意：

沒有比特幣的區(qū)塊鏈？

上周，資產管理界的不少大咖齊聚紐約曼哈頓的“共識：投資”大會共話數字貨幣。在“看漲與看跌”研討環(huán)節(jié)，來自金融新聞網站Real Vision的拉烏爾·保羅提出了一個不少人看跌比特幣的原因——雖然區(qū)塊鏈是一項革命性的技術，其數據庫的安全性也是勿庸置疑的，但這些區(qū)塊鏈最終會被企業(yè)所掌握。這最終會導致像比特幣這樣的公共區(qū)塊鏈的價值變得一錢不值。

不過所謂的“私有區(qū)塊鏈”的概念至少是部分區(qū)解了這項技術的核心安全性。數字加密貨幣吸引了大量分散的“戶主”，他們并不需要對總賬戶的內容擁有所有權，就能確保一個共享總賬戶的信用。區(qū)塊鏈領域的權威觀察人士安德里斯·安東諾波洛斯就指出，所謂“私有區(qū)塊鏈”只是舊瓶裝新酒的老式數據庫。一旦真實世界的區(qū)塊鏈應用運行起來，它們大多數都將基于信用度比較高的公共區(qū)塊鏈，比如比特幣和以太幣等。

分叉是個大問題

邁克·諾沃格拉茨則是一個“嘴上說不要，身體確很誠實”的例子。他一邊說數字加密貨幣是一個泡沫，一邊成立了一支大基金專門投資數字加密貨幣。諾沃格拉茨指出，所有的數字加密貨幣并非都是生來平等的，也不是所有數字加密貨幣都能火起來。比如目前的全球第六大數字加密貨幣——萊特幣，就“沒有添加任何能令它取代比特幣的新東西”。

他最后舉的這個例子是很值得商榷的——萊特幣近來的表明已經證明，它的創(chuàng)新和改良速度可以比比特幣更快。但他的觀點總體上是沒問題的，尤其是考慮到比特幣進來已經出現了嚴重的“分叉”現象，也就是服務器運營商從現有的某種數字加密貨幣分離出來，創(chuàng)建了其代碼和資產的拷貝。這些叉分得越來越細，隨著時間的推移，如果它們不能證明自己的創(chuàng)新能力和競爭優(yōu)勢，像“比特幣現金”（Bitcoin Cash）、“比特幣黃金”（Bitcoin Gold）和“以太幣經典”（Ethereum Classic）這種數字加密貨幣都難逃崩潰一途。

沒有深層價值

Vanguard指數基金之父杰克·伯格歷來眼光獨到，因此你可能認為他一定會對比特幣的創(chuàng)新有所好評。但事實并非如此。

上周在參加美國外交關系學會的一次會議時，杰克·伯格建議聽眾“要像躲避瘟疫一樣躲避比特幣”。他還重復了在比特幣懷疑論者中很流行的一個看法：“支持比特幣的沒有任何東西，你有的只是讓別人掏更多錢接盤的希望?！?

雖然伯格是位投資大師，但他也有看走眼的時候，他的這套懷疑論早就該扔進歷史的垃圾堆了。數字加密貨幣的幣值與它當前的深層價值當然沒有多大關系，但它并不意味著它沒有任何深層價值。數字加密貨幣網絡依托于大量的先進硬件，管理它們的是成千上萬受過高等教育的工程師和業(yè)務開發(fā)者。比特幣天然具有成長為高價值資產的潛力，因為它是一個真正無法攻破且完全開放的全球金融網絡。

如果比特幣是一家上市公司，而不是一個去中心化的網絡，那么現在估計已經不少人忙著做空比特幣了。（數字加密貨幣的另一個特點，就是它很難被做空。）不過沒人會說比特幣的資產沒有價值。

易成為犯罪者的工具

數字加密貨幣另一個老生常談的“原罪”，本周又被諾貝爾經濟學獎得主約瑟夫·斯蒂格利茨提起。他想的可不僅僅是泡沫那么簡單。斯蒂格利茨認為，比特幣是有道德問題的，而且對于全球治理和宏觀經濟有害。上周他對彭博社表示：“比特幣的成功，僅僅是因為它有能力規(guī)避監(jiān)管風險。所以在我看來，它應當是非法的，況且它也不服務于任何社會職能?！?

關于這方面，斯蒂格利茨說的其實并沒有錯。比特幣早期的成功與它充當了不法活動和資金外逃的工具不無關系，現在利用比特幣偷稅逃稅的行為可能也并不鮮見。另外他還有一點說對了，那就是比特幣的核心功能——支付反而并不好用，造成這種現象的原因有網絡擁塞、高昂的手續(xù)費，當然還有幣值的極大波動性。

不過作為一種無法被黑掉的分布式貨幣，數字加密貨幣的長期前景依然是很可觀的。將來，從云計算、網絡叫車到醫(yī)療服務，數字加密貨幣也許都能搞定。而且斯蒂格利茨還忽視了重要的一點——靠監(jiān)管是很難將數字加密貨幣“和諧”掉的。它的服務器可以遷移到任何對它表示友好的國家和地區(qū)（比如那些老式的海外避稅天堂），而且它的訪問簽名也可以輕易被偽裝。

我們并不是在道德上給比特幣作辯護，但這是一個事實。歐美國家的監(jiān)管壓力當然可以讓很多機構投資人甚至對沖基金敬而遠之（這些機構進入比特幣市場的意圖從目前幣值的飆升上就能看出來），但數字加密貨幣在道德上的“陰暗小角落”，卻也確保了它的價值永遠不會下跌至零。（財富中文網）

譯者：賈政景

Bitcoin continues one of the most dramatic price runups of any asset in living memory, posting prices above $11,800 this morning after starting the year below $1,000 per digital token. In its early years, skeptics with little knowledge of blockchain technology were quick to dismiss Bitcoin as a fleeting trend. But as knowledge spreads and prices chase new highs, the skeptics have become more nuanced – and even if you love Bitcoin, they’re often worth listening to.

Here are a few of the most notable bear sentiments being aired as Bitcoin’s rip-roaring rampage continues.

Blockchain without Bitcoin?

At last week’s Consensus: Invest conference in Manhattan, some of the greatest minds in asset management came together to talk cryptocurrency. On a “Bulls and Bears” panel, Raoul Pal of the Real Vision financial news network repeated a favorite saw of today’s more informed bears – that while blockchain database security is a revolutionary technology, those blockchains will ultimately be privately managed by enterprises. That would eventually drive the value of public blockchains like Bitcoin to zero.

But the idea of a private blockchain at least partly misunderstands the core security premise of the technology. Cryptocurrency payouts attract a decentralized swarm of hosts who ensure the honesty of a shared ledger, without necessarily having a stake in its contents. Andreas Antonopoulos, long one of the smartest commentators in the space, has dismissed private blockchains as a fundamentally inefficient replacement for an old-fashioned database. Once real-world blockchain applications are up and running, most will likely be hosted on one of the trusted public blockchains, such as Bitcoin or Ethereum.

What the Fork

Not exactly a bear, Mike Novogratz has said that cryptocurrency is in a bubble, even while also starting a large fund specifically to invest in it. Novogratz has made a point that is far too rare in this realm – that not all cryptocurrencies are created equal, and not all of them will win. As an example, Novogratz has said he believes Litecoin, the 6th largest cryptocurrency, “doesn’t add enough new stuff to replace Bitcoin.”

The specific point is highly debatable – Litecoin has recently proven it can innovate and improve faster than Bitcoin. But the broader point is solid, particularly when it comes to recent “forks,” in which server operators split from an existing cryptocurrency and create copies of its code and assets. Forking spreads network resources thinner and thinner, and over time, if they don’t prove that they offer competitive innovations, forks like Bitcoin Cash, Bitcoin Gold, and Ethereum Classic will crash.

No Underlying Value

Jack Bogle, Vanguard founder and father of the index fund, was a maverick in his day, so you might think he’d have a kind word for Bitcoin’s innovation. But you’d be wrong.

Last Tuesday at a Council on Foreign Relations event, Bogle advised listeners to “avoid Bitcoin like the plague,” and went on to lay out a common sentiment among crypto-skeptics.

“There is nothing to support Bitcoin except the hope that you will sell it to someone for more than you paid for it.”

With all due respect to a titan, Bogle is fundamentally wrong, and this line of criticism should have been buried years ago. Cryptocurrency prices certainly have little relationship to underlying value right now, but that doesn’t mean there’s nothing there at all. Cryptocurrency networks include vast amounts of bleeding-edge hardware, and they’re being managed by thousands of highly trained engineers and business developers. Bitcoin has the potential to grow into something of obviously huge value – a truly unhackable and totally open global financial network.

If Bitcoin were a public corporation instead of a decentralized swarm, it would probably have some extremely aggressive short-sellers right now (actually, the fact that it’s hard to short cryptocurrency is a good reason to be wary of it). But noone would say its assets had no value.

A Tool for Criminals

One of the perennial critiques of cryptocurrency was reiterated this week by Nobel Prize-winning economist Joseph Stiglitz, who has bigger things on his mind than a bubble – he thinks Bitcoin is morally dubious, and bad for global governance and the macroeconomy.

“Bitcoin is successful only because of its potential for circumvention [and] lack of oversight,” he told Bloomberg last week, “So it seems to me it ought to be outlawed, it doesn’t serve any useful social function.”

Stiglitz is right that much of Bitcoin’s early momentum was based on either lawbreaking or capital flight, and the scale of its ongoing use for tax evasion is likely massive. He’s also right that it isn’t currently useful for its core purpose – payments – thanks to network congestion, high fees, and extreme volatility.

But the long-term above-board applications for totally unhackable, distributed ledgers are still waiting in the wings: cryptocurrency could eventually run everything from cloud computing to ride-hailing to health records. And Stiglitz misses a crucial point – it would be very, very hard to regulate cryptocurrency out of existence. Its servers can be moved to any friendly jurisdiction (much like old-fashioned offshore tax shelters), and its traffic signature can be easily disguised.

That’s not a moral defense, but it’s a fact. Regulatory pressure in jurisdictions like the United States and Europe could absolutely keep away institutional investors and even hedge funds, whose future entry to the market is increasingly priced into the current crypto-surge. But its shady underbelly nearly guarantees that cryptocurrency as a whole will never drop to zero value.