The value of skepticism

Al Seckel, an expert on illusions, explores the perceptual illusions that fool our brains. He shares loads of cool tricks to prove that not only are we easily fooled, we kind of like it.

The new breed of high-tech self-monitors (measuring heartrate, sleep, steps per day) might seem targeted at competitive athletes. But Talithia Williams, a statistician, makes a compelling case that all of us should be measuring and recording simple data about our bodies every day — because our own data can reveal much more than even our doctors may know.

Oxford mathematician Peter Donnelly reveals the common mistakes humans make in interpreting statistics -- and the devastating impact these errors can have on the outcome of criminal trials.

When facts are false, decisions are wrong, says editor and TED Fellow Olga Yurkova. To stop the spread of fake news, she and a group of journalists launched StopFake.org, which exposes biased or inaccurate reporting in order to rebuild the trust we've lost in our journalists, leaders and institutions. Learn more about the fight against misinformation as well as two critical ways we can ensure we're not reading (or sharing) fake news.

Legendary skeptic James Randi takes a fatal dose of homeopathic sleeping pills onstage, kicking off a searing 18-minute indictment of irrational beliefs. He throws out a challenge to the world's psychics: Prove what you do is real, and I'll give you a million dollars. (No takers yet.)

The hymen is still the most misunderstood part of the female body. Nina Dølvik Brochmann and Ellen Støkken Dahl share their mission to empower young people through better sex education, debunking the popular (and harmful) myths we're told about female virginity and the hymen.

Known worldwide for her courage and clarity, Christiane Amanpour has spent the past three decades interviewing business, cultural and political leaders who have shaped history. In conversation with TED Curator Chris Anderson, Amanpour discusses fake news, objectivity in journalism, the leadership vacuum in global politics and more, sharing her wisdom along the way. "Be careful where you get information from," she says. "Unless we are all engaged as global citizens who appreciate the truth, who understand science, empirical evidence and facts, then we are going to be wandering around -- to a potential catastrophe."