Quote from: JackH on December 29, 2014, 12:31:09 AM

You imply that Satoshi neither relied on hashcash and b-money as example for what became known as Bitcoin, right? That makes his invention of Bitcoin even harder to understand, since he is not relying on historical solutions that could have led to Bitcoin.

No what I am saying is Satoshi did know about and use hashcash, because he cited it (and wrote to me in aug 2008 to ask for the correct citation). But seemingly he didnt know about B-money from what he told me & Wei Dai, and seemingly didnt know about bit-gold either from what he told Wei. I put links to those things above in the OP, which were collected by Gwern on his blog.

My point is lots of smart internet protocol aware / programmer type people knew about hashcash for 11 years before bitcoin was announced. If hashcash was the only novel required building block (other than very widely known things like digital signatures and hash functions) then the number of people who can code, are interested in internet technology and knew about hashcash is hard to enumerate but must be in the 10,000s if not 100,000s range.

To be clear Satoshi solved some difficult problems that others had tried and failed to find answers for (how to build a distributed ecash system with hashcash mining without creating a centralised mining inflation rate control, ie how to control inflation (bitcoin solves a different problem supply side inflation which is mathematically controlled - others tried to design around price inflation, which seems impossible). But there were others who tried, and independently thought of the problem that needed to be solved. The sybil resistant consensus system reusing the proof-of-work is a neat innovation too.

Adam