Electronic money

Ben Laurie ben at links.org
Sun Dec 7 12:11:00 GMT 2014

On Sun Dec 07 2014 at 11:27:22 AM Francis Davey <fjmd1a at gmail.com> wrote:

> 2014-12-07 10:50 GMT+00:00 Ben Laurie <ben at links.org>:
>> "sorted out"? By who? In a completely decentralised way? (Hint: probably
>> not, how would you?).
> By the parties to the double-spend (something that is always possible).
> Note: I am not arguing against you and certainly not claiming this was done
> in a decentralised way.
> In practice a lot of errors in financial (and indeed more broadly
> commercial) systems are sorted out by agreement that is required neither by
> law nor by code. As I understand it, this was one such example.


>> As I said, you should read my writings on the matter. The title of the
>> second one gives the game away, so clearly you haven't. :-)
> No, I missed the links. Will do.

I lazily didn't sent the links (search for Bitcoin on my blog).


What I was interested in is whether anyone was working with something that
> was (i) electronic money (under the definition of the directive) (ii)
> freely circulating (i.e. not account based) and (iii) not reliant on a
> physical token (as Oyster is).

Oyster is also account-based, right?

I don't believe you can do what you're asking for. If there are no
accounts, how do you prevent double-spend?

> Eg, some cryptographic thing I store on my computer, can email around etc,
> using a distributed protocol but that is also "electronic money".
> I have been given a couple of leads which I will pursue, but the general
> lack of such things in widespread use makes me wonder whether they are
> actually useful, or maybe there are reasons for them not being used right
> now.

Yeah - their impossibility seems like a pretty strong reason.

You quoted Mondex as an example. I think that's wrong: Mondex was
account-based - the accounts live on the cards. The "reference to the
issuer" is in the behaviour of the card, which doesn't double spend because
the issuer programmed it that way (and allegedly, almost certainly untrue,
you can't persuade it to do otherwise).
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