Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population. In this mind-bending talk from TEDGlobal he shows how it works and how similar laws hold for organisms and corporat...

Economics writer Tim Harford studies complex systems -- and finds a surprising link among the successful ones: they were built through trial and error. In this sparkling talk from TEDGlobal 2011, he asks us to embrace our randomness and start making better mistakes.

Michael Moschen puts on a quietly mesmerizing show of juggling. Don't think juggling is an art? You might just change your mind after watching Moschen in motion.

J.D. Vance grew up in a small, poor city in the Rust Belt of southern Ohio, where he had a front-row seat to many of the social ills plaguing America: a heroin epidemic, failing schools, families torn apart by divorce and sometimes violence. In a searching talk that will echo throughout the country's working-class towns, the author details what ...

Backed by mathematical analysis, network theorist Albert-László Barabási explores the hidden mechanisms that drive success -- no matter your field -- and uncovers an intriguing connection between your age and your chance of making it big.

Journalism is a noble calling and the credibility of the profession is at stake. Today, there is weaponization of information and it is dividing us. Ann Curry passionately shares how people are yearning for journalism they can trust. Her Talk powerfully explains that truth leads to trust, which leads to understanding, understanding leads to hum...

Women's equality won't just happen -- not unless more women are put in positions of power, says Sandi Toksvig. In a disarmingly hilarious talk, Toksvig tells the story of how she helped start a new political party in Britain, the Women's Equality Party, with the express purpose of putting equality on the ballot. Now she hopes people around the w...

Rich scientific evidence comes from the history of life on Earth -- we just have to ask the right questions to find it. Whether it's figuring out the cause of the dodo bird's extinction or the bite force of a Tyrannosaurus rex, paleontologist Michael Benton shares some offbeat quandaries from the past, present and future.

Bill Gates hopes to solve some of the world's biggest problems using a new kind of philanthropy. In a passionate and, yes, funny 18 minutes, he asks us to consider two big questions and how we might answer them. (And see the Q&A on the TED Blog.)

When two people are trying to make a deal -- whether they’re competing or cooperating -- what’s really going on inside their brains? Behavioral economist Colin Camerer shows research that reveals how badly we predict what others are thinking. Bonus: He presents an unexpected study that shows chimpanzees might just be better at it.

(Update: the CDC and international science community urge everyone to wear face coverings in public.) Where did the new coronavirus originate, how did it spread so fast -- and what's next? Sharing insights from the outbreak, global health expert and TED Fellow Alanna Shaikh traces the spread of COVID-19, discusses why travel restrictions aren't ...

In this glimpse into our technological future, cryptographer Craig Costello discusses the world-altering potential of quantum computers, which could shatter the limits set by today's machines -- and give code breakers a master key to the digital world. See how Costello and his fellow cryptographers are racing to reinvent encryption and secure th...

In this fascinating conversation, cosmologist and TED Fellow Katie Mack delves into everything from the Big Bang theory to what we see at the edge of the observable universe to a few ways the cosmos might end. Stay tuned to hear Mack recite an original poem on the wonder and marvel of existence. (This conversation, hosted by deputy director of t...

How can we measure what makes a school system work? Andreas Schleicher walks us through the PISA test, a global measurement that ranks countries against one another -- then uses that same data to help schools improve. Watch to find out where your country stacks up, and learn the single factor that makes some systems outperform others.

Insects and animals have evolved some amazing skills -- but, as Robert Full notes, many animals are actually over-engineered. The trick is to copy only what's necessary. He shows how human engineers can learn from animals' tricks.

Physicist Brian Greene explains superstring theory, the idea that minscule strands of energy vibrating in 11 dimensions create every particle and force in the universe.

We're all embedded in vast social networks of friends, family, co-workers and more. Nicholas Christakis tracks how a wide variety of traits -- from happiness to obesity -- can spread from person to person, showing how your location in the network might impact your life in ways you don't even know.

Bruce Bueno de Mesquita uses mathematical analysis to predict (very often correctly) such messy human events as war, political power shifts, Intifada ... After a crisp explanation of how he does it, he offers three predictions on the future of Iran.

Biologist Mark Pagel shares an intriguing theory about why humans evolved our complex system of language. He suggests that language is a piece of "social technology" that allowed early human tribes to access a powerful new tool: cooperation.

Speaking at TED in 1998, Rev. Billy Graham marvels at technology's power to improve lives and change the world -- but says the end of evil, suffering and death will come only after the world accepts Christ. A legendary talk from TED's archives.

Simplicity: We know it when we see it -- but what is it, exactly? In this funny, philosophical talk, George Whitesides chisels out an answer.

Bill Ford is a car guy -- his great-grandfather was Henry Ford, and he grew up inside the massive Ford Motor Co. So when he worries about cars' impact on the environment, and about our growing global gridlock problem, it's worth a listen. His vision for the future of mobility includes "smart roads," even smarter public transport and going green ...

In an exclusive preview of his book The Stuff of Thought, Steven Pinker looks at language and how it expresses what goes on in our minds -- and how the words we choose communicate much more than we realize.

Many of the world's biggest problems require asking questions of scientists -- but why should we believe what they say? Historian of science Naomi Oreskes thinks deeply about our relationship to belief and draws out three problems with common attitudes toward scientific inquiry -- and gives her own reasoning for why we ought to trust science.

In this powerful talk, P.W. Singer shows how the widespread use of robots in war is changing the realities of combat. He shows us scenarios straight out of science fiction -- that now may not be so fictitious.

Feelings are complicated. And even more so at work. We like to believe the ultimate professional is stoic, but what important information do we miss when we disregard our emotions on the job? In this episode, Harvard psychologist Susan David helps us break free from the "tyranny of positivity" and embrace the full range of our emotions. After th...

So the Mars Rovers didn't scoop up any alien lifeforms. Scientist Penelope Boston thinks there's a good chance -- a 25 to 50 percent chance, in fact -- that life might exist on Mars, deep inside the planet's caves. She details how we should look and why.

Greg Lynn talks about the mathematical roots of architecture -- and how calculus and digital tools allow modern designers to move beyond the traditional building forms. A glorious church in Queens (and a titanium tea set) illustrate his theory.

"Babies and young children are like the R&D division of the human species," says psychologist Alison Gopnik. Her research explores the sophisticated intelligence-gathering and decision-making that babies are really doing when they play.

Stephen Wolfram, creator of Mathematica, talks about his quest to make all knowledge computational -- able to be searched, processed and manipulated. His new search engine, Wolfram Alpha, has no lesser goal than to model and explain the physics underlying the universe.