Count well-known author Michael Lewis as a bitcoin skeptic.

"I do get the blockchain idea -- but I don't completely get bitcoin," the author of popular business books such as Liar's Poker and The Big Short told TheStreet in an interview.

Despite the many skeptics of bitcoin, the cryptocurrency has had one heck of a run of late. It recently surged past the $15,000 level for the first time.

The cryptocurrency has seen renewed upward momentum following the Chicago Mercantile Exchange (CME) Group's announcement to launch Bitcoin futures this year.

Meanwhile, Lewis also says he isn't a big fan of Twitter (TWTR) - Get Report .

"When I saw Twitter, I remember thinking if I want to speak in haiku -- like why would I ever do that," Lewis said. "If I have something useful to say, it's not going to happen in two sentences."

Lewis practices what he preaches: he has no Twitter account.

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