To find Satoshi, we are looking for someone very specific, with such a rare set of skills. There are only few people in the world who could match this.
For example, if some kind of crazy VR game came up, with a few awesome features - of all the billions of people in the world, only very few people would even be able to code it. So the entire search space reduces to VR coders, and now we are at just a few thousand of people. The more clues we have, the closer we will get.
So let us gather all the evidence we have about who Satoshi Nakamoto is:
Using the evidence above, we can zoom in on who our most likely candidate is.
A) 35 to 50: Satoshi uses a form of writing that was common on the internet from 2000 to 2010. This style of writing was used in usenet, in sites like slashdot, metafilter and so on. The internet writing style nowadays has changed significantly - people growing up in the 2010 to 2018 internet write completely differently. This naturally ages him.
B) Windows: Satoshi uses a form of variable naming that was common in Microsoft Visual Studio 6. People who professionally coded for windows around that time used that particular variable naming convention.
C) Usenet: Generally, most of the information that Satoshi built Bitcoin on was available in Usenet. It is quite unlikely that Satoshi was only lurking and never posted. He would have posted, but never as the name Satoshi. That means that any serious candidate would certainly have a Usenet presence.
D) Prior Postings: Long before getting involved in the BitCoin project, Satoshi would have left a footprint of his interest in digital money online. It would be impossible for him to have made the anonymous plan, way before he even knew that it would work. There must be some prior postings indicating interest.
E) Math: Bitcoin does not live in isolation - the type of people who research about such things would typically have interests in math, physics, algorithms or encryption. Traces of this would be available online.
F) Prior Art: It is highly unlikely that Satoshi has never released any software, commercial or open source before. Our candidate will certainly have done so before.
Combining all these, a single person keeps on popping up that fulfils all the criteria. Someone who until now has not been linked to the bitcoin founder. A quote about him:
He's very good at his strengths. When he gets an idea in his head, he works it over until he has it solved or knows it can't be solved. I've rarely seen him give up on problems - Len Sassaman
In the year 2000, 9 years before the public release of Bitcoin, he posted on Usenet:
Some tweaks of time-release crypto/non-parallel hashcash In the second technique, Bob would like to prove to Carol that he did some work to Carol without having to get a challenge from her beforehand. To do this, he takes a message he wants to prove he mulled over and hashes it, then squares the result repeatedly (mod N) a total of 10^6 - 1 times, and sends his message and the result to Carol, who takes the hash to the E power and verifies that it's equal to the value Bob sent her squared (mod N). This technique can be made to work for work factors greater than 10^6 by taking the hash of one bit of work and including it in the next repeatedly, but that results in a much larger proof of work than the constant-sized one the previous technique does.
In this message, he is talking to the founder of HashCash. He gets replies from Adam Back, the creator of HashCash, which has often been called the inspiration for Bitcoin.
Who was this person? None other than Bram Cohen, the founder of BitTorrent. The name of his website was BitConjurer.org. It kind of makes sense that he would call his digital money BitCoin, but lets not be hasty in jumping to conclusions yet.
Let's look at the evidence linking Satoshi to Bram Cohen.
First of all, they are both the same age. Bram was born in 1975 and Satoshi was born in 1975. Which fits in quite well with the age we expect Satoshi to be.
Bram invented the big hit software BitTorrent, so he has some good past experience developing big software.
Bram comes from a time when the particular variable naming was common for windows code - basically, he codes like Satoshi
Bram was ousted from BitTorrent as CEO in 2005, and the domain Bitcoin.org was registered in 2008. 3 years is about the right time to develop this.
Bram has shown regular online interest in cryptography, mathematics, puzzles and algorithms
More importantly, the following are true:
The evidence is circumstantial, but there are really very few people who are gifted enough to have come up with Bitcoin. Bram Cohen is one of the few - and he showed interest in this as far back as the year 2000. He is also born in the same year as Satoshi, has very similar opinions, and created software prior to that called BitTorrent.
I could be wrong, but in my opinion, it is possible that Bram Cohen is Satoshi Nakamoto.
Final quotes from Bram Cohen:
I can come off as pretty arrogant, but it's because I know I'm right. I'm very, very good at writing protocols. I've accomplished more working on my own than I ever did as part of a team.
I am a technological activist. I have a political agenda. I am in favor of basic human rights: to free speech, to use any information and technology, to purchase and use recreational drugs, to enjoy and purchase so-called 'vices', to be free of intruders, and to privacy.
You get so tired of having your work die. I just wanted to make something that people would actually use.