Arthur Hayes, CEO of one of the biggest cryptocurrency exchanges in the world, wrote that next month he would “wipe the floor” with the world-famous economist and ardent bitcoin hater Nouriel Roubini, but then deleted his tweet.

On 3 July, Taipei will host a blockchain summit during which fierce debates will be held between crypto enthusiasts and bitcoin opponents. Confirming his participation in the debates, CEO BitMEX Arthur Hayes promised to defend bitcoin in a dispute with one of the most ardent haters of cryptocurrencies, world famous economist Nouriel Roubini.

“I’m going to wipe the floor with that chump,” Hayes promised on Twitter. A few hours later he deleted this tweet.

Nouriel Roubini is a famous crypto skeptic. Roubini, who is also called Doctor Doom for predicting the financial crisis of 2008–2009, has repeatedly criticized bitcoin and forecasted its imminent death.

A few days ago, Roubini reposted an article by Alex Sobel, a member of the British House of Commons, in which he criticized bitcoin.

The Bitcoin Scam: Despite the utopian claims of its proponents, Bitcoin is a right-wing nightmare which facilitates tax evasion, money laundering and environmental degradation. By Alex Sobel, only UK MP with a computer science degree. So science-literate,” Rubini wrote in his Twitter.

In the article Sobel calls bitcoin a set of unsubstantiated promises, utopian and extremely energy-intensive project.