Updated—Friday, October 10
Last weekend, Bitcoin crashed. The dollar value of a single Bitcoin began to decline on electronic markets starting on Friday and by Sunday afternoon had fallen 14%, to $290.
It recovered a bit in the days that followed, but the slide appears to part of a broader trend: At the Thursday price of about $350, the digital currency has lost almost 70% of its value since its all-time high of $1,147 in December 2013. At the New York Times, Paul Krugman used the roller coaster weekend as an occasion to once again call Bitcoin a long con.
But among the Bitcoin faithful, the sun never stopped shining. On Reddit's Bitcoin discussion board, for example, home to almost 140,000 enthusiasts of the electronic currency, the price drop was framed as good news. "The good old days are back! Massive walls, manipulation and a true financial wild west - I love it" chirped one of Monday's most popular posts.
"Who else is enjoying the firesale?" asked another popular participant who claimed to be "picking up tons of cheap bit coin."
How to explain the eternal optimism? Is it possible that Bitcoin's most dedicated fans are simply more tuned in to the currency's long-term potential than the broader market and therefore have a more favorable view of its true value?
Sure, it's possible -- but Meir Statman, a professor at Santa Clara University specializing in behavioral finance, has a more plausible explanation for the findings: Confirmation bias. In short, he says, Bitcoin communities tend to be echo chambers of optimism, giving their members a false impression of the currency's true value. "What you hear, really, is what you want to hear; what is easy for you to believe: That bitcoin is going to take over and banks are a thing of the past," explains Statman. "And when you have people who reinforce it, people are not looking for the truth, they are looking for views that are going to support their prior beliefs driven by ideology and self interest and so-on."
This explanation would seem to be supported by a recent study of Bitcoin users by researchers at the University of Illinois, who found that those who participated in online Bitcoin communities were far more bullish about the currency's future price than other Bitcoin holders. When asked about the long term value of Bitcoin (which the survey defined as the coin's price in early 2019), users who talked about Bitcoin on various online platforms produced estimates 68% higher than those who did not.
Of course, that's not a phenomenon unique to Bitcoin or online forums. "There is a similar finding about communities where people describe their investment success more generally, because people tend to brag about their success and not brag about their losses" the professor warns. "If you are not careful, all you hear is that people are making tons of money."
Statman suggests yet another psychological explanation for the behavior of the Bitcoin community, noting that many people who invest in Bitcoin -- and other alternative assets like gold -- do so in part because it fits their broader global outlook and ideology. "It is fair to say that lots of the people who invest in gold invest in a view of the world: That the United States is going down, bad things are going to happen, inflation is going to rise," Statman says.
That makes hard truths particularly difficult to accept, he says. After all, divesting from a stock is easy. Divesting from a world view, well, that's a lot more painful.
Statman advises investors of all types to avoid confirmation bias and "ideological" investing by talking to people with different perspectives. For example, he jokes, Bitcoin buyers should have asked his opinion of the currency before last weekend. His take: "I think it's a scam."
After being contacted by Bitcoin advocates, Statman clarified his position to MONEY. "My initial thought when I heard about Bitcoin from my students is that is a scam. I know now that the technology of Bitcoin might prove useful but I am puzzled by the rush to it."