Thank you for your response, that does make sense. It's going to be
interesting to follow what is going to happen!

2015-05-14 3:41 GMT+12:00 Gavin Andresen <gavinandresen@gmail.com>:

> On Tue, May 12, 2015 at 7:48 PM, Adam Back <adam@cypherspace.org> wrote:
>
>> I think its fair to say no one knows how to make a consensus that
>> works in a decentralised fashion that doesnt weaken the bitcoin
>> security model without proof-of-work for now.
>>
>
> Yes.
>
>
>> I am presuming Gavin is just saying in the context of not pre-judging
>> the future that maybe in the far future another innovation might be
>> found (or alternatively maybe its not mathematically possible).
>>
>
> Yes... or an alternative might be found that weakens the Bitcoin security
> model by a small enough amount that it either doesn't matter or the
> weakening is vastly overwhelmed by some other benefit.
>
> I'm influenced by the way the Internet works; packets addressed to
> 74.125.226.67 reliably get to Google through a very decentralized system
> that I'll freely admit I don't understand. Yes, a determined attacker can
> re-route packets, but layers of security on top means re-routing packets
> isn't enough to pull off profitable attacks.
>
> I think Bitcoin's proof-of-work might evolve in a similar way. Yes, you
> might be able to 51% attack the POW, but layers of security on top of POW
> will mean that won't be enough to pull off profitable attacks.
>
>
> --
> --
> Gavin Andresen
>
>