I just came across Why This Computer Scientist Says All Cryptocurrency Should “Die in a Fire”. I can't find any point in there that hasn't already been refuted many times. But it's relatively rare to find so many of them in one place, and it has been going around, so I thought I should make a little effort to rebut it.
Security
Though not the most important aspect of the article, the "computer scientist" in the title is a not-too-subtle argument from authority, so it behooves us to take a look. The computer scientist in question is Nicholas Weaver, who I haven't heard of before, though from a brief look at his publications, I recognize some of his co-authors. It seems like his expertise is network security. So his most important contribution as an expert would be if he could find an actual technical security problem in Bitcoin. But of course he hasn't, in fact no one has successfully exploited Bitcoin. This is a rarely appreciated aspect of the network. Even though it's the world's largest honey pot, with literally several hundred billion dollars there for the taking, the entire codebase is open source, and all the data is on the public blockchain, no one has actually technically been able to "crack" Bitcoin. There is plenty of theft of Bitcoin of course, because people make mistakes with their keys etc. A scary bug was luckily fixed in the early days. Still no one has exploited the system itself. For any computer scientist, or anyone who has ever written software, this is very remarkable. As a network security expert, you'd think Weaver would at least mention it.
Maybe he has motivation for not saying anything positive? Indeed, apparently he's been declaring the death of Bitcoin so many times since 2013 that Weaver has earned a place in the Bitcoin Skeptic Hall of Fame. It seems like he has dug himself into an anti-Bitcoin emotional trap which is hard to climb out of.
Bubbles
Credentialism aside, his actual criticism consists of economic arguments. He points to the price of Bitcoin in USD and "bubbles" where it rose from $10 to $100 then "crashed". Then to $1000 and crashed. Then to $20,000 and crashed. Then to $60,000 and crashed. And confidently asserts that there won't be a fifth bubble, that this time it's really dead. But this only inadvertently points to the fact that he's been wrong so many times. Without any coherent explanation of why his previous predictions have failed, it's hard to believe him this time. A more honest view is to zoom out and look at it on a log scale, and notice that each "crash" bottoms out much higher than the previous one. So if one is going to reason purely from historical prices, then a reasonable observer would not confidently say that the last peak happens to be the final one before it goes to zero forever. That's like looking at a toddler learning how to walk and after the fourth time he falls down saying the kid will never walk. A more reasonable take is that if the Bitcoin price chart tells us anything, it's more likely the story of an emergent store of value. Of course, chart analysis to predict future prices is generally a fool's errand, and even more so with this unique phenomenon. There are not many analogues in history -- we don't have exchange rates of gold from 2500 years ago. It's better to think about Bitcoin from first principles and think about long term adoption while avoiding short term price predictions.
Adjacent crypto: altcoins, blockchains etc.
To make matters more confusing, most critics (and Weaver is no exception) put Bitcoin in a bucket with all the other cryptocurrencies, ICOs, NFTs etc. But almost all of the other stuff around "crypto" is junk, much of it unethical or even fraudulent.
Leaving aside the many outright frauds, the whole "altcoin" space reminds me a bit of the history of the Internet. In the 1980s and 90s, TCP/IP had alternatives like ATM (Asynchronous Transfer Mode). A lot argued that the IP network wouldn't scale, or wouldn't offer good enough QoS, etc. They argued that the net would never be used for serious things like the phone network or television. It's true that there are various trade-offs in the design of TCP and IP, even some arbitrary choices. You can argue for different ones in hindsight. And things do evolve, albeit slowly. Witness IPv6 getting deployed in a backward compatible way over more than 2 decades, while IPv4 continues to chug along. Even ATM was absorbed as a short-lived layer 2 protocol under IP. But there's only one Internet. That's the so-called network effect. If the protocol is good enough, early enough, it becomes the standard.
And that is where proponents and critics of "altcoins" are causing confusion and driving unjustified hostility to Bitcoin. Viewing Bitcoin as one of many "cryptocurrencies" masks a basic reality: Bitcoin is like the Internet of money and it is here to stay.
That said, I'm not against all other cryptocurrencies. For example a broader smart contract platform makes sense long term, and Ethereum may be the one for the ages. But there are significant technical hurdles remaining. And it's already so bloated very few people actually run a full Ethereum node. And that's all before the much delayed eth 2.0 migration, which if it succeeds may introduce a potentially fatal governance change called proof-of-stake. Building a "world computer" as it needs to be is much harder than what has been achieved to date.
"Blockchain not Bitcoin" is another common theme among "crypto" hopefuls. But without a real reason for decentralization, a blockchain is just an expensive and slow database. Most of the envisioned applications for blockchains can be more easily achieved with traditional databases.
Bitcoin's proof-of-work ledger for sound commodity money is to date the only real world blockchain use case.
Energy and Proof-of-Work
Speaking of proof of work, energy use is the most common and dangerous vector of FUD against Bitcoin, and Weaver recycles the usual points. He claims that Bitcoin miners are "wasting tons of electricity". This topic is deep and generally misunderstood. Here's my attempt to distill it in my paper entitled "Dynamics of Bitcoin mining":
Does mining use too much energy?
This question assumes the system requires some amount of computation to be done and that it ”wants” to minimize the energy to achieve it. That is indeed how most systems work. But not Bitcoin. Proof-of-work does the reverse of that. The system ”wants” a certain value to be spent on energy, and the amount of computation adjusts to achieve it. Of course individual miners compete by being as efficient as possible, but the resulting collective behavior is to achieve a certain cost of energy with variable amounts of computation, not to perform a specific amount of computation with variable amounts of energy.
This unusual combination – individual participants being efficiency-seeking but their collective behavior being efficiency-neutral – is very counter-intuitive and probably the root cause of much misguided hostility. It’s also worth emphasizing that the amount of energy doesn’t matter, only the cost. If the price of electricity relative to everything else in the world doubles, but nothing else changes, then Bitcoin would simply use half the amount of energy to achieve the same relative cost[...] The cost of energy is a feature not a bug, and ”waste” is impossible by design. All of the energy is ”work”.
And where there’s no ”waste”, the question of energy use boils down to a moral judgement. Can you argue that heating in the winter, even if perfectly efficient, is not justified and people should move to warmer climates? What about air conditioning, or electric clothes dryers, or ice cream? When is any purposeful energy use justified? Morally, as long as access to and the price of energy is fair, what it’s used for should be accepted as a subjective choice. Bitcoin offers the possibility of inflation-resistant savings, low-cost long-distance value transfer, and censorship-resistant money. For its users, these are important benefits which are no less justified than most other uses of energy.
In the same interview, Weaver attacks the notion that Bitcoin "incentivizes green power", and goes on to misrepresent the incentives, and the supply and demand dynamics of electric power. I covered this too in the same paper:
Many sources of renewable energy are highly variable: solar and wind power depend on time of day and weather, hydroelectric power is seasonal, etc. In general, these ups and downs on the supply side do not line up perfectly with the demand for electricity. Further, even with the largest possible batteries, water reservoirs, etc., electric energy remains extremely difficult to store for later use at a large scale. Thus there is often a lot of ”stranded” energy when using renewable sources. Just like off-peak bandwidth in telecommunication networks, or empty seats on scheduled airline flights, the cost of production is already sunk, and so for the supplier, selling stranded power at any price is better than letting it go unused. [...] The competitive dynamics of Bitcoin mining are such that it shifts in time and space to the lowest available cost of electricity. This occurs not just by deploying hardware to various locations, but also by turning miners on or off instantly. This flexible demand-side support makes mining the ideal customer to balance variable supply, and as variability tends to affect renewable much more than fossil fuel sources, in effect, Bitcoin subsidizes the development of ”green” electricity.
Adoption
Finally, Weaver claims that Bitcoin will permanently fall apart Real Soon Now™, when it runs out of suckers. But there's really no basis for his claim. He doesn't give any reason why the number of suckers is a particular fraction of the world's population and why that limit has been reached now. Why didn't it run out after 1M people? Or 100M? Why not 8 billion people?
Of course, the success of Bitcoin depends on widespread adoption. Why is gold used as money? You can try to explain it based on some key properties: it's impossible to synthesize, the supply is limited, it's fungible and can be shaped easily, it doesn't degrade... Those are useful, but we don't know if they are sufficient. The emergence of a monetary good is a fascinating topic, one that most people don't understand and don't even realize that they don't know. ("The Origins of Money", an article which predates Bitcoin, is a good read). Ultimately, Bitcoin is just a Schelling point whose emergence is highly path dependent.That's just a fancy way of saying "we'll see", but every day that passes makes the ultimate success more likely, and it's been almost 5000 days already.
No comments:
Post a Comment