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.

The more you think about it, the more complex time travel seems! This video explains a key paradox that is one of the main reasons for this.

John Searle's thought experiment, called "The Chinese Room," presents an argument against the idea that computers could ever be truly intelligent.

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?

Founded by writer Dave Eggers, the Brooklyn Superhero Supply Company is a sister project of the San Francisco Pirate Supply Company, both of them storefront covers for their real work, the 826 educational assistance program. See how creative minds have banded together to make learning fun and at the same time creatively fund educational assistance!

This animated video shows how tuberculosis, still a very common disease, spreads and is fought by our bodies. Find out more about MSF’s work treating tuberculosis around the world.

"Elephants Dream" is a short animated film, created by the Orange Movie Project in Amsterdam using almost entirely open-source software. Whether a dream, or hallucination, or reality – Emo is not sure what he thinks of the machine, which Proog practically worships, until he makes a serious mistake...

The gravity of the situation is clear – and yes, it’s going to hurt. But what are a few broken bones when the alternative is plummeting to your doom? Lonely Planet, the largest travel guide book publisher in the world, suggests we learn to laugh in the face of adversity with their How to Survive Anything series, of which this video is an episode.

This classic American cartoon from the 1940s tells the story of the most famous reindeer of all, Rudolph the Red-Nosed Reindeer. Shunned by his peers for his unusual appearance, he’s called on by Santa for a special job on Christmas Eve!

All of the ridicule turns to love and acclaim as Rudolph’s unique nose becomes a beacon in the darkness, lighting Santa’s way on that dark and foggy Christmas Eve.

The Tom and Jerry cartoon has been a classic since it first came out in 1940. America's favorite rivals now take their cat-and-mouse game to the big screen – coming to theaters in 2021.

Learn about the role of the sea in global warming. The global conveyer belt is part of the large-scale ocean circulation that is driven by differences in the density of the ocean waters. It plays a key role in keeping the climate in balance and Europe warm. Global warming may change it forever with unforeseeable consequences.
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The group is concerned about global and environmental issues. They want to take action, but must find a base to work from. Meanwhile, off the coast of Brittany, a new environmental disaster is occurring...

Maestro listens as the kids tell him about all the things they see going wrong in the world, their fears, and their frustration that so little is being done. He wants to know if they have any solutions.

Maestro shows what can happen at conferences on the environment, where the blame is passed from person to person and little is resolved. But he also sees the necessity of paying attention to such issues, and encourages the kids to continue with their own plans to promote change.

Traveling aboard the flying globe that Maestro himself has invented, the young environmentalists set out to see the situation in other parts of the world up close.

Maestro takes the kids across the world to show them what is being done to deal with the worst issues related to waste and pollution.

The kids are frustrated with how slow things seem to be progressing, but Maestro boosts their enthusiasm with some good news: Their search for a workspace is over, and a new environmental movement is born — The Guardians of the Planet!

It’s very warm for November, and the kids are playing outside. They’re convinced that the greenhouse effect is responsible for the unusual weather, and think it could make a good subject for the next issue of their newspaper.

Maestro speaks about the Earth’s atmosphere, and explains how the greenhouse effect is changing the planet’s ability to regulate its own temperature. The kids want to know what is being done about the problem, and what the outcome might be.

The Gulf Stream plays a big part in maintaining the temperatures we are used to, and Maestro explains that if it is interrupted, parts of the world could become colder as an unexpected result of global warming.

When a message arrives from an Inuit correspondent, a small team sets off to investigate the environmental changes that threaten the delicate balance of life in the frozen north.