Below are 3 emails 2008-2009 between cryptographers Wei Dai & Satoshi
Nakamoto; they were quoted in the Sunday Times’s 2 March
seeking Satoshi; From nowhere, bitcoin is now worth billions. Where
did it come from? Andrew Smithset off to find Satoshi Nakamoto, the
mysterious genius behind the hit e-currency.
They are the earliest documented communications by Satoshi Nakamoto:
Sent: Friday, August 22, 2008 4:38 PM
To: “Wei Dai” <firstname.lastname@example.org>
Cc: “Satoshi Nakamoto” <email@example.com>
Subject: Citation of your b-money page
I was very interested to read your b-money page. I’m getting
ready to release a paper that expands on your ideas into a complete
working system. Adam Back (hashcash.org) noticed the similarities and
pointed me to your site.I need to find out the year of publication of
your b-money page for the citation in my paper. It’ll look like:
 W. Dai, “b-money,” https://www.weidai.com/bmoney.txt, (2006?).You can download a pre-release draft at
https://www.upload.ae/file/6157/ecash-pdf.html Feel free to forward it to anyone else you think would be interested.Title: Electronic Cash Without a Trusted Third Party
Abstract: A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without the burdens of going through a financial institution. Digital signatures offer part of the solution, but the main benefits are lost if a trusted party is still required to prevent double-spending. We propose a solution to the double-spending problem using a peer-to-peer network. The network timestamps transactions by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work. The longest chain not only serves as proof of the sequence of events witnessed, but proof that it came from the largest pool of CPU power. As long as honest nodes control the most CPU power on the network, they can generate the longest chain and outpace any attackers. The network itself requires minimal structure. Messages are broadcasted on a best effort basis, and nodes can leave and rejoin the network at will, accepting the longest proof-of-work chain as proof of what happened while they were gone.
The second email in the sequence is the reply by Wei:
Here’s the archived post:
There are some discussions of it at
Thanks for letting me know about your paper. I’ll take a look at it and let you know if I have any comments or questions.
It is worth noting that the paper provided by Satoshi in this exchange is an early draft of what would become the Bitcoin White Paper. The full copy of that draft has been lost but a similar draft is available here.
Sent: Saturday, January 10, 2009 11:17 AM
Subject: Re: Citation of your b-money page
I wanted to let you know, I just released the full implementation of the paper I sent you a few months ago, Bitcoin v0.1. Details, download and screenshots are at www.bitcoin.orgI think it achieves nearly all the goals you set out to solve in your b-money paper.
The system is entirely decentralized, without any server or trusted parties. The network infrastructure can support a full range of escrow transactions and contracts, but for now the focus is on the basics of money and transactions.
There was a discussion of the design on the Cryptography mailing
list. Hal Finney gave a good high-level overview:
| One thing I might mention is that in many ways bitcoin is two independent
| ideas: a way of solving the kinds of problems James lists here, of
| creating a globally consistent but decentralized database; and then using
| it for a system similar to Wei Dai’s b-money (which is referenced in the
| paper) but transaction/coin based rather than account based. Solving the
| global, massively decentralized database problem is arguably the harder
| part, as James emphasizes. The use of proof-of-work as a tool for this
| purpose is a novel idea well worth further review IMO.