Kimberly White/Getty Images for Vanity Fair
Twitter cofounder and chairman and Square CEO Jack Dorsey speaks onstage during 'From 7 Dwarves to 140 Characters' at the Vanity Fair New Establishment Summit at Yerba Buena Center for the Arts on October 9, 2014 in San Francisco, California.
"It's disappointing, but reflective of the world," Dorsey said. "We see as much optimism as we see negativity."
He went on to explain that he sees Twitter as "empowering dialogue" so that people can talk about issues.
Lauer asked Dorsey whether he ever gets trolled on the site. "I get some complaints. I get some nastiness every now and then," Dorsey said.
Most people would just block someone if they're getting abuse online, but Dorsey hasn't done so. "I've never blocked anyone. I want to see what people are saying and I want to hear from them," he said.
Dorsey isn't the only famous person who has never blocked anyone on Twitter. Another high-profile user who has the same policy is President Obama. A 13-year-old child in the US claimed that he had been blocked by the President, a claim that was quickly denied by the White House.
Public Service Announcement: Nobody is or has ever been blocked from the @POTUS twitter account
- Frank Benenati (@Benenati44) September 23, 2015You can view the first part of Dorsey's Today show interview here, and the second part here.