Replying to Avatar waxwing

An interesting essay from Vitalik Buterin a few years ago, that I missed at the time:

https://vitalik.ca/general/2019/04/03/collusion.html

In the first half he nicely elucidates concrete reasons behind an intuition I've always had: that using game theory to build decentralized financial systems always suffers because they have a dependency on identity (and how I'd put it: the problem with that fundamentally, comes from the fact that identity is a fiction, an arbitrary and unanchored construct).

This problem manifests as the impossibility of avoiding collusion in various forms.

Quote:

"But in the version of game theory that allows for the possibility of coalitions working together, called cooperative game theory, there are large classes of games that do not have any stable outcome that a coalition cannot profitably deviate from."

This is the problem - a lot of academic game theory posits isolated actors, however that is *never* the real world (see: sockpuppets or simply, communication!). That's why I've always told people, just like Nick Szabo did to Manfred Karrer back in the days of bitsquare, "don't rely on game theory, replace it with cryptographic verification").

He then correctly identifies, in the middle of the article, the best solution to the collusion problems described: proof of work, because it is identity-less.

The remaining part of the article feels like a reach, looking for increasingly Byzantine (pun intended) partial solutions to what he clearly understands to be an insoluble problem.

Proof of Work relies on game theory as well as Cryptography. Just like Proof of Stake. Both systems can be used without real-world identities.

The crucial difference I think is what Saylor said: PoW is inherently tied to the thermodynamic reality. PoS isn't.

That changes the incentives for PoS to a politicized consensus, just like central banking. In theory both could work. But of course, that's not reality.

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Interesting points, thanks.

I agree re: real world anchor, see this that I wrote a few years ago:

https://reyify.com/blog/pow-a-pictorial-essay

The game theory basis of pow for consensus is about as simple as it gets, it's like "minimally game theory dependent" somehow. I don't think it's really correct that bitcoin consensus depends on non-real world identity in the same way as PoS; yes miners mine coins to addresses, but they are purely ephemeral. With stake, it's really not quite like that; those ephemeral identities/accounts are used as *inputs* to consensus.

Great article!

...Yes, basically in PoS I literally have to convince someone to sell/send me coins while in bitcoin anyone could just mine coins without permission.

I just need to start generating hashes in whatever way I can.