【Terms of service】

Edward Snowden thinks the answer to hate speech is Terms of serviceto drown it out with other voices.

The former NSA contractor-turned-whistleblower spoke with Twitter CEO Jack Dorsey via video on Tuesday, and touched on Twitter's struggle to figure out how to handle those who use the platform to spread hate.

"The answer to bad speech is not censorship," Snowden said. "The answer to bad speech is more speech."

Twitter has at times seemed to agree and disagree with Snowden on that point. The social media platform has become proficient at banning accounts that recruit for and promote ISIS, suspending some 235,000 extremist accounts from its service as of August. It also recently barred many accounts that espoused white nationalism. Both moves are obvious instances of a social media company controlling the speech allowed on its platform. Yet the company isn't devoted to this type of censorship.

After an initial suspension, Twitter reinstated perhaps the most prominent white nationalist in the United States, Richard Spencer. And though users have issued complaint after complaint about being harassed on the platform, many feel Twitter often does little to combat the nastiest behavior with which it is associated.

Twitter and other social media companies ramped up their efforts to track down and block ISIS accounts and messaging this year after not-so-subtle nudges from government officials. And several tech giants recently announced the goal to build a joint database in which they'd be able to track terrorist photos, videos and messages across platforms.

And this is where Snowden and these companies seem to differ. Snowden's obviously not a fan of ISIS, but he's worried about the definition of "terrorist."

"Nobody wants to see ISIS recruiting on the internet," Snowden said. "But at the same time there is no common definition of terrorism that's recognized around the world." What happens when "terrorist" is defined as "political opponent," for example?

Dorsey, microphone in hand, moved on to his next question.