1. Where does it come from?
2. How do we know for sure that it's Nick Szabo?
I don't know. All I know is it was linked from this page: http://dave.liberty.me/2014/05/02/who-is-satoshi-nakamoto/ with this statement regarding it: "**edit – 6/7/2014 – a picture of Nick Szabo at a 1997 conference has since surfaced (via Adrian Chen)". Don't shoot the messenger
It would be an incredible story if it were Nash or if he were a significant player.
But that man in that picture looks like a BOSS! Looks like he could dismantle a government with 10 lines of code. It would also be quite interesting if he was Szabo, reminds me of an irl Bruce Banner.
It would be quite surprising to me, and I would be just as happy to know it were Szabo, some random dude no one otherwise knows in the general public sphere. However I cannot comprehend the coincidences between Szabo, Satoshi, and Nash's works. There are very few people in the history of man that have a such a wholistic view to produce such knowledge. Szabo's blog seems like random posts about random subjects, but if you really read it wholistically and understand the different directions in points to, the person behind them has an extensive understanding of the history of man up until present day and future technologies and social systems.
I can't help but think the information presented and alluded to in the szabo blog would take a lifetime to accumulate.
Szabo also backhandedly (not sure if correct word) solved many previously known but unsolved "problems" that really needed bitcoin to solidify them as proofs. He sort of "metaphorically" slid in solutions without presenting them in an academic form. And this is why I understand bitcoin to be a unifying solution, once the person had the concept of "bitcoin" all of a sudden they could privately run around "solving" all sorts of problems previously thought not solvable. Law, programming, economics, cryptology, quantum physics, quantum computing, history, archeology, and who knows what else.
My understanding is "someone" has pretty much won every academic award out there...
I seems really clear to me if someone has read the majority of Szabo's blog, it is a past/present/future account of everything that has to do with bitcoin and it was started in 1995.