This ancient mathematical trickery posits that a mighty hero cannot overtake a tortoise. Zeno of Elea (born c. 490 BCE) is the author of this and other paradoxes.

How can one brother travel into space and return younger than his twin? In just sixty seconds, a startling side effect of Einstein’s Theory of Relativity is explained to us.

Plato is considered one of Philosophy’s greatest writers. He was able to conceive of greater realities by imagining how much poorer our perception would be if we had lived our whole life as prisoners locked in a cave.

The trolley problem is a classic thought experiment in moral philosophy. Is sacrificing one life to save the lives of many others the best possible outcome?

Abi tells us a little about the history of the origami paper crane, from its significance in Japanese culture to her own personal contact with this powerful modern symbol of hope and goodwill.

Continuing to pirate audaciously, Blackbeard sails up the eastern coast of the United States, where, incredibly, he secures a pardon from the Governor of North Carolina. Setting up base on an island, he is soon plundering ships again, but by now has made some determined enemies and faces capture, dead or alive.

The city of Oxford is home to some 150,000 residents and a famous seat of learning, the oldest English-speaking university in the world. Although the exact date of its founding isn't known, it is said that local priests and monks were first taught in monastery schools in the area in the eleventh century.

Even if you're not the biggest fan of school, you've got to admit it's better than the historical schools depicted in this series! They certainly had some questionable moral codes and weird punishments...

Not long ago, in Welsh schools, the pupils weren’t allowed to speak their native language, Welsh! There was no choice but to learn English. In the Victorian classroom, learning is dull and repetitive, but today’s lesson is not going exactly as the teacher has planned.

After Victoria became Queen, English children’s names became really weird. A girl called Never… a boy called Toilet… For one poor teacher, taking the class register is almost impossible!

Some of the schools in Georgian England were very rough places! In this video, a prospective pupil and his parents get caught up in a full-scale schoolboy rebellion while on a tour with the headmaster. They even encounter flying masonry and gunfire!

In the middle of Manhattan, there is an ancient Egyptian monument with carved hieroglyphics. John informs us of its vital statistics and lasting significance.

We’ve all seen footage of the first men walking on the moon... but how exactly did they get there? This video details the fascinating, many-faceted construction of the Apollo 11 spacecraft so that we can see exactly what happened in what order to make this incredible journey a reality.

Ellis Island, the U.S. gateway to immigration from distant lands, has been reopened to visitors, following significant damage from Hurricane Sandy. A visit there, and to the nearby Statue of Liberty, can be emotional, even for those born in the U.S.

Join Karine as she goes behind the scenes at the University of Oxford, one of the world’s oldest and most prestigious educational institutions and alma mater to kings and presidents.

In this video, you can learn all about Oxford, England, a beautiful university town steeped in history. There are many places of interest spread among the many colleges that comprise the university.

Filmmakers Christina Fon and Stevie Salas are interviewed about Rumble, their documentary exploring how Native American musicians have influenced rock n' roll.

Stevie Salas and Christina Fon discuss what is next for the film Rumble: The Indians Who Rocked the World as it premieres around the world.

Over the course of human history, thousands of languages have developed from what was once a much smaller number. How did we end up with so many? And how do we keep track of them all? Alex Gendler explains how linguists group languages into language families, demonstrating how these linguistic trees give us crucial insights into the past.

What does the Holocaust have to do with us, anyway? In part two, Roderick Miller, the chair of the nonprofit organization Tracing the Past, gives a talk at TEDxVienna about the Holocaust and contemporary Europeans' perception of the space they live in.

What does the Holocaust have to do with us, anyway? In part three, Roderick Miller, the chair of the nonprofit organization Tracing the Past, gives a talk at TEDxVienna about the Holocaust and contemporary Europeans' perception of the space they live in.

Andy Beem (Windsports, CA) and Billy Vaughn (Kitty Hawk Kites, NC) talk about flying 1895 Lilienthal and the 1902 Wright glider replicas, and engaging with the history of human flight on a tactile level.

Are you interested in aviation? Here's the first chapter of a documentary about the invention of the airplane entitled Kitty Hawk: The Wright Brothers' Journey of Invention.