"An advanced city is not one where even the poor use cars, but rather one where even the rich use public transport," argues Enrique Peñalosa. In this spirited talk, the mayor of Bogotá shares some of the tactics he used to change the...

We've all heard that robots are going to take our jobs -- but what can we do about it? Innovation expert David Lee says that we should start designing jobs that unlock our hidden talents and passions -- the things we spend our weekends...

Why build a virtual world? Philip Rosedale talks about the virtual society he founded, Second Life, and its underpinnings in human creativity. It's a place so different that anything could happen.

We each want to live a life of purpose, but where to start? In this luminous, wide-ranging talk, Jacqueline Novogratz introduces us to people she's met in her work in "patient capital" -- people who have immersed themselves in a cause, a...

Kayla Briet creates art that explores identity and self-discovery -- and the fear that her culture may someday be forgotten. She shares how she found her creative voice and reclaimed the stories of her Dutch-Indonesian, Chinese and...

Giorgia Lupi uses data to tell human stories, adding nuance to numbers. In this charming talk, she shares how we can bring personality to data, visualizing even the mundane details of our daily lives and transforming the abstract and...

As the child of an Afghan mother and Pakistani father raised in Norway, Deeyah Khan knows what it's like to be a young person stuck between your community and your country. In this powerful, emotional talk, the filmmaker unearths the...

What's it like to grow up within a group of people who exult in demonizing ... everyone else? Megan Phelps-Roper shares details of life inside America's most controversial church and describes how conversations on Twitter were key to her...

* Viewer discretion advised. This video includes discussion of mature topics and may be inappropriate for some audiences. What really causes addiction -- to everything from cocaine to smart-phones? And how can we overcome it? Johann Hari...

As human beings, we get used to "the way things are" really fast. But for designers, the way things are is an opportunity ... Could things be better? How? In this funny, breezy talk, the man behind the iPod and the Nest thermostat shares...

In which John Green explores F. Scott Fitzgerald's novel of the Jazz Age, The Great Gatsby. John introduces you to Nick Carraway, Jay Gatsby, Daisy and Tom Buchanan, and the other characters in the novel, and tries to look beyond the...

How do we define worth in society, and who gets status? Sociologist Michele Lamont studies these questions and investigates ways to broaden the circle of recognition and fight the harm of social stigmatization. She lays out the steps...

It's an unexpected side effect of globalization: problems that once would have stayed local—say, a bank lending out too much money—now have consequences worldwide. But still, countries operate independently, as if alone on the planet....

What makes work satisfying? Apart from a paycheck, there are intangible values that, Barry Schwartz suggests, our current way of thinking about work simply ignores. It's time to stop thinking of workers as cogs on a wheel.

* Viewer discretion advised. This video includes discussion of mature topics and may be inappropriate for some audiences. Marina Abramovi's art pushes the boundary between audience and artist in pursuit of heightened consciousness and...

Pastor Rick Warren, author of "The Purpose-Driven Life," reflects on his own crisis of purpose in the wake of his book's wild success. He explains his belief that God's intention is for each of us to use our talents and influence to do...

It sounds like science fiction, but journalist Stephen Petranek considers it fact: within 20 years, humans will live on Mars. In this provocative talk, Petranek makes the case that humans will become a spacefaring species and describes...

Conventional wisdom might have you believe that human beings only really start showing empathy after a few years of learning social norms and morals. However, some research suggests that this kind of compulsion to do good might be...

What does Kendrick Lamar have in common with Disney's "Moana"? They recognize our common humanity and show us how to love ourselves and one another, says writer and educator Chloé Valdary. She shares how she uses pop culture to help...

We believe a lot of things because we've been told - from our personal acquaintances and also experts. With so many belief systems being passed to us, how do we know whom to trust? Using contemporary examples, Ram Neta explains when...

If you change your city, you're changing the world, says Eric Garcetti, mayor of Los Angeles and chair of C40 Cities, a network of the world's megacities committed to tackling the climate crisis. He shares tangible ways Los Angeles and...

In which John Green teaches you about Chinua Achebe's 1958 novel, Things Fall Apart. You'll learn about Igboland, a region in modern day Nigeria, prior to the arrival of the British Empire. Achebe tells the story of Okonkwo, an Igbo...

Ocean explorer Robert Ballard takes us on a mindbending trip to hidden worlds underwater, where he and other researchers are finding unexpected life, resources, even new mountains. He makes a case for serious exploration and mapping....

How successful are we compared to other species? It turns out that biomass, or what things weigh, can be more important than how many of something there are. Find out how our numbers stack up against everything from bugs to bacteria, and...