At 3:15 AM +0300 4/16/01, Sampo Syreeni wrote:

On Sun, 15 Apr 2001, Tim May wrote:

...

But the "paving stone," or touch stone, I want to bring up is this: the role of third party escrow agents.

Escrow is practically useless unless Esther can verify that both parties have kept to their promise. If the data Esther keeps is encrypted, this will not, barring ZKPs, be possible. In an anonymous economy, having the data in a usable form will give Esther an incentive to use up the tradeable goods escrowed by Bob. Anonymity also gives her a real possibility to do that, unlike with traditional escrow. Of course there are a host of nasty complications, like how different sorts of tradeable items might be protected from this sort of conduct (e.g. anonymous cash probably could be protected from Esther, while sensitive corporate memos being sold to a competitor perhaps couldn't), and the possibility of linking Esther to the damage done to Bob in different kinds of transactions. Nevertheless, I think this is a valid objection.

The canonical example is of an escrow agent handling a deposit by a buyer of an untraceable killing. When the killer presents the appropriate form of evidence that this happened, and that he or she was "there" (*), the escrow holder pays. "You slay, we pay!" (Details of what the evidence might be are for the market to shake out.) (I have been using this example since 1988. Not as an advocacy of contract killings, but as an illustration of the issue. This scheme is different from AP, which is a lottery form.) Can the buyer of the hit renege? The escrow agent already holds the digital cash. (This assumes nonrepudiable digital cash.) --Tim May -- Timothy C. May tcmay@got.net Corralitos, California Political: Co-founder Cypherpunks/crypto anarchy/Cyphernomicon Technical: physics/soft errors/Smalltalk/Squeak/agents/games/Go Personal: b.1951/UCSB/Intel '74-'86/retired/investor/motorcycles/guns