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

From: Gareth Williams <[email-masked]>
Date: Sun, 27 Apr 2014 22:53:08 +1000

On 27/04/14 11:42, Christophe Biocca wrote:> This seems like splitting
hairs, no? A block isn't a guarantee (it can
> get orphaned). And as a user of bitcoin (as opposed to a miner), this
> change cannot affect any payment you ever receive.

Disagree. Maybe we just have a fundamental disagreement about what
Bitcoin is? :)

Bitcoin is this perfect /trustless/ mathematical machine, built - most
unfortunately - upon a foundation of mushy humans.

We depend specifically upon these three assumptions:
1. >50% of hashpower will not cooperate to rewrite history
2. the economic majority will not cooperate to reinterpret history
3. enough people believe in the illusion of artificial scarcity to give
it real value

Given that the above hold, from there up the system operates completely
trustlessly, with predictable security parameters. (Of course a block
isn't a guarantee of anything, but I know the probability that you can
cause a re-org from depth N with X% hashpower, which allows me to reason
about security.)

Now, some people on this thread might point to the above 3 points and
say "that isn't really a trustless system, it's a democratic system."
And then advocate that we can do without assumption 2, 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."

That moves us away from a pure trustless system built upon a small
democratic foundation (as something of a necessary evil in an imperfect
world where humans run our computers and use our system) and toward a
"democratic system".

You don't have to agree, but I hope you can understand the point I'm
making :-) It's a fundamental shift in the nature of the system, and to
some people a violation of the social contract. Definitely not splitting
hairs.

I feel I've now consumed rather more bytes of everyone's inboxes than I
ought to have with this topic. I appreciate you and Mike taking the time
to reply to a newbie/lurker.

-Gareth