Why Proof of Stake won’t be used for intergalactic first contact: A Bitcoin Astronomy essay

Ethereum’s “merge” to full Proof of Stake has put the consensus mechanism top of mind for many, and I thought it would be a good opportunity explore what—to me—was one of the most mind-blowing implications of Dhruv Bansal’s prior Bitcoin Astronomy III piece: PoS’s subjectivity means it can never scale to an intergalactic, interspecies society.

The Hash Horizon’s Shadow

A long time ago, in a galaxy far, far away a civilization developed. It was a social society, made up of self-interested individuals who lack “perfect” knowledge (no hive-mind Formics here). Like life in our own galaxy, they evolved in a world with finite resources that demanded competition for survival. This galaxy exists in a universe that follows the same natural laws as our own. Assuming no Zones of Thought where the rules of relativity can be broken, the same Terran laws of physics must apply.

This civilization is known across the cosmos as the Nakamotans.

By following three rules of Cosmic Sociological evolution of civilizations as laid out in Dhruv Bansal’s Bitcoin Astronomy Part III, a theory for the universality of PoW blockchains can be seen. An evolutionary pattern takes shape whereby this civilization will develop some form of money as a trust-minimizing technology to facilitate economic coordination amongst disparate communities of self-interested individuals. This will eventually take the form of a blockchain for settling economic activity in a trust-minimized way, and, by the laws laid out in Bitcoin Astronomy parts I and II, this blockchain should be secured by Proof of Work (PoW) or risk civilizational stagnation and galactic irrelevancy.

The Nakamotan blockchain is called Xenocoin and, as Bansal writes, it is “the largest, most valuable, and lowest time-preference blockchain in their civilization. In many ways, it is their civilization.”

What good is such a monument to technological and economic achievement if it couldn’t be used as a tool to spread the glories of the Nakamotan empire?

An interesting implication of The Law of Hash Universality—which first shows not just how, but why a (PoW) blockchain like bitcoin will be used to establish first contact with an alien civilization—is that we can use the same underlying thesis to show why Proof of Stake (PoS) cannot be a mechanism in the same way.

Proof of Work is based on the laws of physics

A universal law can be understood to be an objective, observable, and eternal description of some facet of the universe. As such, they can be independently discovered by disparate societies living within the same universe as long as both societies are able to observe the same facets of that universe. It may not be known as Newton’s Law to the Nakamotans, but they will likely have discovered that “every particle attracts every other particle in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.”

Similarly, we can assume that electricity, the number π, relativity, and any other universal law of nature can be eventually discoverable or taught by any civilization given sufficient technological advancement and time because they are all features of our natural universe. They are also prerequisites to so many other innovations required for civilizational (and interplanetary) expansion.

Money and language as technology

Language and money are similar types of innovation, but social ones. The best monies survived because they could transcend culture, appealing to certain fundamental laws.

Precious metals worked as money because any civilization could get access to them given sufficient resources and technological advancement. You could prove the legitimacy of metal coinage without understanding the language or culture of the party being traded with, i.e. both universal and trust-minimized. Characteristics such as fungibility, divisibility, durability, and portability were universally valuable for any social, trading society without even ever having to express this reasoning.

The universal (at the terrestrial scale) value of what was considered “good” money also created a self-reinforcing process of innovation. The drive to participate and dominate these economies drove advancements across nations in business, shipping, navigation, military, and geology. This cycle perpetuates human flourishing: To scale beyond a barter system requires money; the best money is universally valued; intra-civilizational competition for access to this money drives innovation; innovation in turn promotes economic growth; growth increases the difficulty of competition for access to money; this difficulty increase drives more innovation.

Money, like language, is a necessary innovation that must be developed for any civilization that has developed according to the rules of Cosmic Sociology laid out above. Blockchains similarly will arise to allow this money to scale to match advancements in telecommunications (telephones, fax machines, TCP/IP, mobile phones). As knowledge becomes more valuable and data transmission more instantaneous, faster and trust-minimized transfer of value becomes an ever-growing imperative.

From these patterns of universality, we can start to see how Proof of Work will become the only mechanism that survives as the consensus protocol for any sufficiently advanced space-faring civilization. In the words of Ethereum founder and lead developer Vitalik Buterin: “Proof of Work is based on the laws of physics, so you have to work with the world as it is.”

As such, it is also the case that a Proof of Work block is the most likely means by which first contact is made with another alien civilization, as I’ll explain below.

Introducing the Buteranians

In the farthest regions of the expansive trading empire of the Nakamotans, there is a group that believe that they can improve upon Xenocoin by taking more direct control of the currency. They believe that the perpetual pressure applied by the Proof of Work that secures their intergalactic economy represents a waste of resources.

These are the Buteranians.

Rather than incentivize ever more efficient means of harnessing energy, this band of rebels believes such commodities should be preserved, if possible indefinitely. To them, the laws of the universe represent an impediment to their ambitions of designing a universe that behaves in the way they believe it should. The rules are simply an obstacle, not to overcome, but rather to ignore entirely.

The Buteranians want to design a blockchain for a society of like-minded individuals, either with similar goals of resource preservation or trust in the designers of such a system to optimize for the goals they represent. The Buteranian Council of Efficient Resource Allocation and Output Maximization (the BCERAOM) offers to convert the existing stores of Xenocoin of their collective into a new currency that anyone will be able to verify and whose supply and security will be guaranteed by a system carefully designed to achieve the goals set out by the council.

One of the last Xenocoin blocks mined by the Buteranian system is received by the rest of the Nakamotans participating in the Xenocoin network and in it is encoded a message sent from the celebrations of their supposed emancipation of their Proof of Work induced oppression:

Proof of Work is based on the laws of physics, so you have to work with the world as it is … whereas because Proof of Stake is virtualized in this way it’s basically letting us create a simulated universe that has its own laws of physics.

Thus XenoPoS was born.

It’s hard to know exactly how the civilization of the Buteranians developed over the centuries since their last Xenocoin block transmission. Their new system operates in an economic universe that incentivizes the priorities of their own culture at the expense of the objective laws of physics foundational to the Nakamotan empire.

Interstellar imagery shows a stabilization of population growth and halted interplanetary expansion within their solar system within the following two Xenocoin blocks. Occasional transmissions received from that corner of space, however, show an explosion in virtual experimentation within the subjective universe of their blockchain. New, relative blockchains are birthed within their system and die out faster than the Nakamotans put out trading outposts. Nothing in these transmissions reveal much to motivate the re-establishment of trading relations.

But like their cousins the Nakamotans, the Buteranians are social and curious. They also believe they have the superior way to structure society. With this familiar drive to make first contact with new civilizations, they have to figure out what kind of message to send.

Et tu Nakamotans?

If choosing to send a signal to make first contact, would our two intergalactic civilizations send a cryptographic puzzle, a sonnet by the Nakamotan Shakespeare, or perhaps a Non-Fungible Bored Buteranian?

The universality—the objective reality of “the world as it is”—inherent to the mathematics underlying the puzzle makes the answer pretty clear. A sonnet would have no subjective reference for a discretely evolved civilization to grab onto. “A rose by any other name” only has cultural significance when you know what a rose is or why it matters that it would still smell sweet, whereas cryptography is just math and every technologically advanced society will have math.

And what else is a blockchain but a cryptographic puzzle? This is even true for PoS where the rules of the cryptographic signatures and one-way hashing functions are based on certain rules of mathematics that should be transferable.

A PoW blockchain makes an excellent message to send out for first contact. It tells you a civilization’s rough age, the energy that they are harnessing, and more. As illustrated in Bitcoin Astronomy III, Proof of Work helps resolve the Fermi Paradox by explaining how the absence of proof of life in the universe is simply a reflection of our own society’s sluggish progress towards a sufficiently advanced, PoW-secured economic system.

From this perspective, we see how deficient Proof of Stake is for the purposes under discussion.

With a XenoPoS blockchain used for first contact, once the receiving civilization (i.e humanity receiving XenoPoS) has “solved” the block and interpreted it, what next? We can’t actually do anything with it nor is our interpretation of much use to the Buteranians. Humanity can demonstrate we understand the network but we can’t participate in it. A “simulated universe” is self-evidently not universal. PoS for first contact at best tells us about the complexity and hubris of that civilization’s imagination.

As Friedtoshi Hayamoto might have written in The Fatal Galactic Conceit:

The curious task of the Proof of Stake mechanism designer is to demonstrate to Buteranians how little they really know about what they imagine they can design.

This is not super useful to anyone and could even be dangerous. Subscribing to the Dark Forest theory of the universe, part of the point of first contact would be to establish the relative danger another civilization poses and determine whether or not a first-strike Xenocide might be prudent.

A more optimistic option for first contact is to use it for productive means by establishing a profitable trading network with the civilization as quickly as possible. If the potential for future prosperity sufficiently outweighs the risks of intergalactic destruction and the cost of establishing such potential were made sufficiently worthwhile, first contact can be more likely to be used for positive ends as opposed to that envisioned by The Dark Forest.

Traders and merchant princes

One of the first things early human explorers would do when finding foreign societies was to establish trade. Exchange of physical goods was step number one; coinage quickly followed. Trade was thus the foot in the door to establishing cross-cultural relations.

But physical trade does not scale to a galactic level. The gap between exploration, first contact, learning to communicate and finding some medium of exchange that we could trust would be inefficient at best, and dangerous at worst. A star system 100 light years away would take 100 years to receive the first message, and another 100 to respond (not counting time to interpret). If we develop space travel that can travel at 1% the speed of light then it would take us… 10,000 years to travel with our goods in tow (and we’ll just ignore the issue of time dilation).

This is why blockchains as a universal principle of Cosmic Sociology is so important. These messages and therefore the very money itself can travel near the speed of light. In economies where information can be a tradable good itself, this makes the amount of time it takes to start participating in an interstellar, cross-civilizational economy shrink by orders of magnitude.

Xeno Phone Home

What happens when the conduit for first contact is a PoW block? Upon receipt, humanity is able to learn quite a bit on our own, bringing with it the possibility for technological advancement and providing a roadmap to more easily bootstrap trade relations:

• We learn something of the energy required to transmit the message
• We learn about their cryptographic capabilities, likely even learning new, more secure techniques for our own use
• Their blocktimes tell us about how far their civilization has spread (see The Second Law of Bitcoin Astronomy)
• We can even start to piece together some of their language (figuring out the math, the serialization, etc.)

Some of this is true with the XenoPoS block. Only with the Proof of Work Xenocoin block in hand, however, does humanity have everything it needs to immediately participate in the Nakamotan economy… entirely permissionlessly.

How this story plays out will depend a lot on where we are as a civilization, but as has already been repeated throughout human history, the drive to participate in the economy of this advanced society would spur a new Golden Age of innovation, not least of all an order of magnitude leap in harnessing energy production because the first group of humans able to mine a block on the Xenocoin chain would be entitled to the block rewards and transaction fees of the hardest, scarcest money in the known galaxy.

XenoPoS, on the other hand, would require the coin to be gifted to us for participation and would further require humanity to trust whatever source of randomness that is dictated by the Buteranians for being chosen as a validator. This would be a “simulated universe” after all that adheres to whatever subjective laws its creators feel they should be and thus totally unknown and unknowable to humanity.

So, what have we learned?

1. We established that blockchains and Proof of Work are universal, independently discoverable characteristics of the universe
2. It follows from #1 that a PoW blockchain is the most efficient and likely means to establish first contact with alien civilizations
3. PoW blockchains allow for a mutually beneficial, intergalactic, cross-civilizational relationship thus facilitating the advancement of galaxy-spanning Kardeshev Type 2.x+ civilizations
4. This is only possible w/ a blockchain that adheres to objective physical laws and is impossible via the subjective “virtualized” ones in “a simulated universe that has its own laws of physics” inherent to Proof of Stake.

You don’t have to believe in Proof of Work, but the universe does. To ignore this is to risk stagnation at best, tyranny or civilizational collapse at worst. Rarely does civilization advance, grow, or flourish by adhering only to virtualized, subjective rules that are by definition exclusionary.

I don't believe in proof of work!

— vitalik.eth (@VitalikButerin) December 25, 2018

Why should we care? Well, first because it’s fun to think about space and aliens and interstellar travel. But almost as important is that it has implications for earthbound life.

In the words of the great Cosmic Sociologist Dhruv Bansal: “PoS cannot support interstellar commerce in the future for the same reasons it should not support global commerce today. This may not be the first reason to dismiss PoS, but it may also be the best reason to do so.”

As shown, PoW’s universality is what makes it permissionless. How do we imagine an Iranian or Russian under international sanctions might become an equal participant in a blockchain network where the largest holders could easily be legally punished for providing the starting capital for such entities to become a validator? Proof of Work simply requires participants to reach sufficient technological advancement to harness the energy and compute power necessary to join. Not only is this the most just system, but such universality is a prerequisite for surviving at the timescales implied when planning for a galaxy-spanning civilization.

Special thanks to Dhruv Bansal whose incredible three part essay on Bitcoin Astronomy was foundational inspiration for this post and to Phil Geiger for encouraging me to write it and flesh out the ideas further.

Several images in this article were generated using OpenAI’s DALL-E 2.