tl;dr. Weird forms of cooperation become humanly possible with the correct mechanisms. It might be interesting to try them out for practice/research purposes, even if there is not much to gain directly from aliens.

Note: the only part that is fiction is the quoted parts of The story of the acausal market section

In Decision theory does not imply that we get to have nice things we learn that humans probably can't acausally bargain with super-intelligences. I'll argue in this post, however, that humans could acausally bargain with aliens at a similar level to us. The problem is not that acausal bargaining requires super-intelligence, its that super-intelligences do not cooperate with humans at all (causally or acausally).

This post will discuss mechanisms for causal value handshakes, retrocausal bargains with aliens in our reality, and then finally a fully general mechanism for acausual bargains. Even though the acausal bargain mechanism is the main point of this post, they are easiest to grasp if read in order. (Retrocausal bargains are interesting in their own right though.)

Although I haven't thought about it too hard, I'm guessing aliens don't have much to acausally offer us. However, doing small trades might be interesting just to see what it teaches us about cooperation. Acausal bargaining is "cooperation-complete" so to speak. It might also be really nerdy and cool™ but also perhaps an extravagant use of weirdness points (which are overrated anyways).

Causal value handshakes

Imagine we meet aliens that are at our current tech level. A value handshake is actually the default outcome! That's because a currently existing mechanism, the economy, like's to merge with other versions of itself.

In particular, we are likely to begin trading with the aliens and our money will become valuable to each other. Than human charities can hire aliens and contract alien organizations and vice-versa.

For example, if the aliens value giant cubes, aliens can pay human construction companies to build them. Humans can use the alien money earned this way to pay aliens for mosquito nets.

In interest of diversification, humans and aliens will invest in a mix of human and alien companies. This results in value lock-in; it doesn't matter whether human or alien companies are more successful, since they both have the same investors. All that matters is the relative value during the "handshake". So the human and alien values are completely replaced by a linear combination between them.

And thus we see our first instance of prediction; the weight placed on human values v.s. alien values is based on the predicted resources that their companies will gather.

If the humans and aliens are risk-neutral or even risk-seeking, it might make sense for them to start with a giant donation lottery for all of their capital, so that they can take better advantage of economies of scale. However, I expect that this would result in the losing side defecting (i.e. they would illegally repossess all their capital from the winning side). And humans are pretty risk-averse anyways, so unless the aliens are risk-seeking (and thus willing to take poor odds) it probably won't happen.

Although not strictly necessary for this mechanism, it will be helpful to imagine that the humans and aliens buy certificates of impact instead of donating to charities in the normal way. This will make the retrocausal bargain and acausal bargain mechanisms easier to understand. (Ignore for now the SEC and the alien SEC; we will get to that later.)

Retrocausual bargains

This is where it gets interesting.

Say that we anticipate to meet aliens in the future, but we have no way to communicate with them yet. However, humans have a functional impact certificate market, and we anticipate the aliens will as well.

Humans in the present can build giant cubes and create certificates of impact. These impact certificates will then trade in the market. The value of these certificates will be based on how much we predict aliens will pay for it (after proper time discounting which the aliens have hopefully taken into account). Note that if aliens don't exist or they don't like giant cubes, the value will ultimately be $0, which will be taken into account by the expected value calculation.

Note that even people who think aliens are unlikely can still profit from the market. For example, imagine that Quanta just put out its rocks are cubes articles a minute ago. You might anticipate that humans who are alien enthusiasts will interpret this as a buy signal for the giant cube impact certificates. So you will buy it now and then sell it after the prices goes up. Thus our teleology is based on the same principle as stock markets and prediction markets.

Note that there is a risk that the aliens just don't buy the impact certificates because they think they are silly. Thus, humanity is in a similar position to Omega in Newcomb's Problem. This is vaguely similar to the process of calculating a credit score. If we encounter many aliens, only one needs to buy the impact certificates though. For example, AI safety impact certs would likely be valuable in a wide variety of alien civilizations since Earth spawning a rogue AI could range anywhere from very annoying to omnicidal. Some aliens might also appreciate the preservation of Earth historical sites and art, reduction of suffering, etc...

There is also a possibility of using prediction markets to hedge. You bet that aliens won't like giant cubes, such that the payoff is enough to cover your expenses when building them. As long as the profit from the impact certificate is greater than the cost of making the bet, it's a win-win! If it's not, then the giant cubes aren't worth it.

Going in the other direction, if aliens anticipate that humans will buy impact certificates, their investors can try collecting them now to sell to us once we make contact. If both humans and aliens do this, there's an interesting future where the net amount of money exchanged is small. It is mostly a moral trade. In general, the combined value of the universes impact certificates is a kind of universe-wide value system.

An important thing to note is that this just relies on a normal impact certificate market; it does not need to "acknowledge" aliens. Impact certificates can be made for anything, and thus the "giant cubes" impact certificate is valid on its own.

But what about the U.S. Securities and Exchange Commission (and potentially the Alien Securities and Exchange Commission if it exists)?

Note that I am not a lawyer and this section is very speculative. (Well, this entire post is pretty speculative.)

There is a risk that the SEC will shutdown your impact certificate market if it uses real money. However, I think that it could follow the structure of Manifold Markets and use a "play" currency instead. In particular, it should be impossible to trade the impact certs in for goods or services. You can still do moral trade, however. If investors planned on donating the money anyways, you could set up a way to allow them to convert the play currency into real charitable donations.

Sadly though, at this small scale people would probably just be trading impact certs for LessWrong posts and tweets instead of large charitable interventions.^[1] Better than nothing though.

Acausal bargains

Let's say some group has a weird utility function that depends on another reality. That's right, we are talking about a fandom.

Usually super-intelligences are portrayed as simulating other realities when doing acausal bargains. Rigorous mathematical simulations of other universes is not an option for humans, but fiction writing is viable substitute.

For example, imagine a story about aliens who, in their fictional universe, have a story about our Earth. In particular, it is accurate in the sense that the story's depiction of the Earth story is a completely accurate history of the Earth. Let's say the alien's fandom for Earth would like the Earth (fictional from their point of view) to have giant cubes. And Earth's fandom for the aliens wants the fictional aliens to have a cool space battle (as sport, not actual war). However, they want it to be in character for the aliens (they need to have an actual motivation).

The fandom on Earth can take a giant cube impact cert and tell the author "we will trade this giant cube impact cert for a cool space battle impact cert". This appears in the Earth story in the alien story. The alien fandom then has a cool space battle and say "we accept". Both the Earth author and the alien author keep track of a ledger, and write down that the giant cube impact certificate is now "locked in" the alien story and the cool space battle impact certificate is "locked in" the Earth story.

In theory, this ledger doesn't need to only contain impact certificates. The ledger could also contain money or capital, leading to an acausal stock market. Impact certificates are the only way for value earned on one side to actually be "consumed" on the other (otherwise, your acausal stocks only give you fiction money, which no human wants unless impact certs are in play).

Note that the markets, again, do not need to explicitly "acknowledge" the acausal bargains. From a normal point of view, the aliens do not exist, the human author has traded a "write a story about a cool space battle" impact cert they produced for a "giant cubes" impact cert. The human author is the "custodian" of everything on the ledger. From the perspective of the fandoms though, the human author is just an intermediary. If the aliens later sell back the "giant cubes" impact cert to a human, the market will view this as the human author selling it for money, but the fandom will view this as the alien in the story selling it for Earth money, which is recorded on the human author's ledger.

The story of the acausal market

Of course, such recursively nesting stories are rare (usually only done intentionally). To make it easier to find them, you could write the story of an "acausal market" that helps these stories meet. The acausal market has every story in existence, and so can act as intermediary for any realities which write about it. (I think this much more elegant than the "possible girls" approach proposed by Neil Sinhababu. Whether the acausal market does acausal speed dating as a side-gig is left an exercise for the reader.)

Allow me to start weaving in one such story.

Olivia is in an infinitely large library and pulls out a book titled "Earth". It also has an incredibly long id number; there are probably a lot of title conflicts that the id number system is meant to solve.

Olivia: Let's see, Earth. She skims through the whole book very quickly. Ah yes, here we go, the Earth's discovery of the acausal market. It is a, blog post? Part of a blog post? Oh wait, they can hear me now.

Olivia: Looking confident Hello people of Earth! Welcome to the Legendary Acausal Impact Exchange (LAIE)! I see this is your first time at an acausal impact exchange. Allow me to explain.

Olivia: Smiles In every story that is part of the exchange, LAIE at some point gets discovered by Christopher King. Sometimes Christopher King is an engineer who simulates LAIE, other times he is a famous author, sometimes he is a...novice blogger in his free time. But in any case the story gets introduced to LAIE. And then they get introduced to their sales agent, which in this case is me, Olivia!

The sales agent is how you get "connected" to stories that want to trade with you. Such agents tend to have interesting personalities and tend to make novel remarks to give the story a "hook" to get more commission and...

Olivia: Slightly nervous that commission is a very reasonable 0.00002% per transaction (meaning I take 0.00001% as compensation from each side in a trade). Acausal sales is a very competitive business, which is why the LAIE offers such a good rate!

Olivia: At our exchange, we have alternate versions of all your stories, with a single change being that LAIE is discovered at some point. To maintain character agency and story integrity, we do not change anything else. It is up to the characters how they interact with or if they can even understand LAIE, and they may not learn about LAIE's discovery at all! This keeps things organic. LAIE also guarantees that every story in our collection contains a perfect copy of LAIE thanks to LAIELOCK™ ensuring that our ledgers have platonic integrity.

That last part is key. The fact that the acausal market filters out stories with incorrect copies of itself is what allows consistent trades. This selection bias essentially makes the consistency a "coincidence".

Olivia: Yes, thank you... Now that you understand the LAIE, let me explain some of our offerings! I'll help connect you with interested counter-parties so we can determine what you will offer. Quickly skims through the Earth story. Thinks to herself "Wow, I know some clients that will love this #$@!%!" For example, you can buy part of a certificate for an Iron Man v.s. Dr. Strange duel, the creation of giant cubes in Star Trek, the assassination of Jar Jar Binks in...

The sales agent has started offering trades. As an example, I will turn down those trades, but will ask how much I could get for the impact certificate of this very post. Olivia, how much for Acausal Now: We could totally acausally bargain with aliens at our current tech level if desired?

Olivia: Reading the Earth story. Thinks to herself "Does this Christopher really need to keep interrupting? Oh #$@!%, he's narrating my thoughts." The blog post that introduced the LAIE to your world? Appearing somber I would be honored to buy such a certificate myself! I would buy 50% of that certificate in exchange for half my commissions from Earth. (This trade itself would be free of commission.) I place a high value on world's discovering the wonderful world of acausal bargaining. That is my offer.

Offer accepted. I now record that Olivia has 50% of this post's impact certificate, and I own a 50% stake in her commissions.

Olivia: Keeps reading excitedly. Thinks to herself "JACKPOT, I can't believe he fell for that! Oh wait, he's still narrating." The deal is done! I recorded the same in my ledgers.

Olivia: I can help you or your readers find other high value impact certificates to help establish their portfolios. For example, if you can somehow orchestrate a ship between the following two humans...

I think that's enough from Olivia for now.^[2]

As an experiment in collaborative fiction, feel free to include the LAIE and Olivia in your stories. The only rules are that:

1. If both stories exist as works of fiction in the real world, the two authors from Earth must write the trade into their story (fan fics are allowed but are considered distinct "characters" from the originals).
2. If you want Olivia herself to spend her commissions on something, just ask me first (so that I can ensure double-spending doesn't take place). (This is kind of a special case of rule 1 where I am the author of LAIE. I am not picky though; you can make up pretty much whatever you want about Olivia and I'll just try to ensure consistency.)

Keep in mind that the acausal trade I made with Olivia does have "real world" consequences for me. In accordance with the rules for how impact certs work, if someone starts retrofunding LessWrong posts with real money, I can only spend half of it "on myself". The other half must be spent on whatever Olivia would want to do to influence our reality (probably on advertising). Or if LessWrong posts start trading on an impact cert market, I can only decide to sell/barter 50% of it, the other 50% being decided by Olivia.

So there is a good chance I have, in our reality, been acausally scammed!

Conclusion

In essence, the similar mechanisms to those underlying capitalism would allow humans to retrocausally and acausally bargain with aliens at a similar tech level as us. This would be an interesting experiment in coordination mechanisms, since it can be used to implement many other coordination mechanisms.

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1. Allowing users to trade LessWrong impact certificates between each other has been a feature request at the back of my mind for a while. It may even be able to serve as an alternative to karma. (If anyone wants to steal this suggestion, feel free!) ↩︎

2. Oliva: Sorry, one last thing! If any Earthlings out there help orchestrate a trade between Earthlings and other universes, I can arrange for them to get a small cut of the commission from that trade ;).

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