It’s not a bad guess. Back has long been an influential figure in crypto circles, and is also famous as the inventor of Hashcash, a form of digital money that predates Bitcoin. Back is also CEO of an early Bitcoin infrastructure firm known as Blockstream, and is currently operating a company that issues shares to amass a hoard of Bitcoin.
In his exposé, which runs to an eye-glazing 12,000 words, Carreyrou seizes on Back’s business activities and layers on heaps of circumstantial evidence to make the case he has found Satoshi. Carreyrou doesn’t produce any smoking guns, but instead relies heavily on characteristics that are attributable to both Satoshi and Back: the use of British spelling, libertarian beliefs, involvement in the Cypherpunk movement, and the employment of punctuation like “proof-of-work” used in the Bitcoin white paper.
Carreyrou acknowledged an obvious objection to this thesis—that there is a lengthy paper trail of Back corresponding with Satoshi—but explains it away by saying that Back was actually writing to himself as part of an elaborate ruse to throw would-be unmaskers off the trail.
It all sounds good until you recall that journalists, like anyone else, are prone to confirmation bias. This is the psychological phenomenon in which people seek out evidence that confirms their existing beliefs and ignore facts that might refute them. Confirmation bias is what tripped up Newsweek and HBO, and it appears to have tripped up Carreyrou as well.
The evidence he provides about Back’s involvement with the Cypherpunk movement and his political beliefs support his case—but are also attributes common to nearly everyone else in the early Bitcoin days. As for the common literary quirks between Back and Satoshi, Carreyrou himself acknowledges they are not dispositive.
Even as Carreyrou frantically pursues every scrap of information that might confirm his thesis, he is quick to gloss over a better suspect that is right under his nose. That suspect is the reclusive polymath Nick Szabo who ticks all of the same boxes as Back and whose initials are conveniently the inverse of Satoshi Nakamoto. What’s more, you can make the case Szabo is Satoshi without having to explain away mounds of correspondence as an elaborate ruse concocted years after Bitcoin’s invention.
Finally, Carreyrou engages in what looks like another serious instance of confirmation bias. He seizes on specific moments from his encounters with Back where the would-be Bitcoin inventor appears to shuffle and prevaricate in the face of tough questions. Carreyrou accepts this as proof he has his man—but rejects another equally compelling explanation.
There is also the commonsense test. Would the inventor of Bitcoin, knowing that exposing his identity would make him the target of every criminal and tax authority in the world, repeatedly sit down with journalists to discuss the topic? Or would they do their best to fade into the shadows?
The temptation to unmask the inventor of Bitcoin is understandable. It is one of the most delicious mysteries in tech, and one that a series of prestigious media brands have failed to solve. Alas for Carreyrou and the Times, they appear to be the latest in a growing list of big swings-and-misses.
