Subject: Re: [Bitcoin-development] Coinbase reallocation to discourage Finney attacks

From: Adam Back <[email-masked]>
Date: Mon, 28 Apr 2014 14:41:02 -0700

On Sun, Apr 27, 2014 at 10:53:08PM +1000, Gareth Williams wrote:
>Bitcoin is this perfect /trustless/ mathematical machine [...]
>
>2. the economic majority will not cooperate to reinterpret history
>
> [this proposal was...] replacing it with:
> 
>2. the economic majority will not cooperate to reinterpret history
>against any good guys, only against bad guys; "please trust their good
>judgement."

Nicely put.

I agree the idea of a populist vote to redistribute or remove mining reward
is an inelegant thing which would probably devolve into politics.

I think the reason that it would likely work out badly is that its not
provable, and so no consensus rule can be constructed requiring proof, so
then it risks devolving to a political decision.  

Step 1: Finney attackers for hire anonymize their blocks (publish via Tor,
use a different reward address for each block, and each pool miner). 
Demanding identification of blocks is generally undesirable for the
objective of avoiding centralization and policy abuse.  Dont even think
about demanding identity, there is no identity in a distributed system.

Step 2: people send tracer payments through Finney attackers, and use that
evidence to decide to vote away their reward.  (However the proof is
non-transitive so people can vote anyway they like for any reason).

Step 3: Finney attackers vote down other pools to make the point.

Adam