'Misinformation' is a hot topic these days, with social media platforms being accused both of helping to spread it and of doing too much to stop it. But who decides what is misinformation, and how does one distinguish it from what is merely an unfamiliar idea or unpopular opinion that might be true after all? Are social media platforms shutting down important discussion by labelling plausible theories as misinformation? Should free speech protections apply to social media sites? Jonathan speaks with AI researcher and misinformation specialist Robert Moro of the Kempelen Institute of Intelligent Technologies, about just these questions.