Stuart Firestein teaches students and “citizen scientists” that ignorance is far more important to discovery than knowledge.

With a jet-powered wing attached to his body, Yves Rossy expands the possibilities of human flight.

Physicist Jim Al-Khalili and co-author Johnjoe McFadden, a biologist, explore the far edges of quantum biology in their book "Life on the Edge."

As founder and CEO of Amazon.com, Jeff Bezos defined online shopping and rewrote the rules of commerce, ushering in a new era in business. Time magazine named him Man of the Year in 1999.

During his 20-year tenure as president of UMBC, Freeman Hrabowski has helped students of all backgrounds pursue degrees in arts, humanities and the sciences.

Mike O'Sullivan postulates that the 30-year era of globalization is now over and that we are entering a new, uncertain -- but increasingly values-driven -- world order.

Student Ludwick Marishane invented a water-less bathing lotion and was named the 2011 Global Student Entrepreneur of the Year Award -- all because he didn't feel like taking baths.

Through the Global Citizen platform, humanitarian Hugh Evans has created an online community of millions of people -- all driven to eradicate extreme poverty by the year 2030.

Ad exec Jose Miguel Sokoloff has led a multi-year marketing campaign that's helped Colombian guerrillas realize that they are wanted back home.

Janine di Giovanni reports from war zones around the world.

Marvin Minsky is one of the great pioneers of artificial intelligence -- and using computing metaphors to understand the human mind. His contributions to mathematics, robotics and computational linguistics are legendary and far-reaching.

Doris Kearns Goodwin writes insightful books on the US Presidency (JFK, LBJ, FDR and Lincoln, so far), telling each president's personal story against the backdrop of history.

Caroline Phillips' rich, soprano voice conjures up the far-and-wide cultures of the world, especially the sound and language of the Basque Country.

With Freeman Dyson's astonishing forecasts for the future, it was hard to tell where science ended and science fiction began. But far from being a wild-eyed visionary, Dyson was a clear and sober thinker -- and one not afraid of controversy or heresy.

A paper on carbon nanotubes, a biology lecture on antibodies and a flash of insight led 15-year-old Jack Andraka to design a cheaper, more sensitive cancer detector.

The writer and presenter of the BBC Radio 4 series "A History of the World in 100 Objects" and the accompanying book.

A writer and a part-time cyborg, Rebecca Knill embraces the humor in her bionic journey while balancing life as a deaf person with cochlear implants which enable her to hear.

Over thousands of archived and broadcast interviews, StoryCorps founder Dave Isay -- winner of the 2015 TED Prize -- has created an unprecedented document of the dreams and fears that touch us all.

Chetan Bhatt teaches and writes about the numerous dangers human rights face today from resurgent Far Right movements.

TED Fellow Kayla Briët explores themes of identity and self-discovery in multiple mediums of storytelling: film, multi-media arts and music.

Marcel Dicke wants us to reconsider our relationship with insects, promoting bugs as a tasty -- and ecologically sound -- alternative to meat in an increasingly hungry world.

Stacy Kauk is working to generate global demand for carbon removal, enabling new companies to prove their impact and scale and spend millions per year to drive down future prices.

Jane Fonda has had four extraordinary careers (so far): Oscar-winning actor, author, fitness guru and impassioned activist.

Rajesh Rao seeks to understand the human brain through computational modeling, on two fronts: developing computer models of our minds, and using tech to decipher the 4,000-year-old lost script of the Indus Valley civilization.

Gillian Tett is chair of the editorial board and editor-at-large (US) of the Financial Times.

Nancy Frates and her family have raised a projected $160 million for ALS research in 2014. How? They kicked off the ALS Ice Bucket Challenge to honor 29-year-old Pete Frates.

Naoko Ishii leads the Global Environment Facility (GEF), a public financial institution that provides around US$1 billion every year to help tackle our planet’s most pressing environmental problems.

Most people look at cardboard tubes and see something fit for the recycling bin. But architect Shigeru Ban turns them into beautiful buildings.

Garry Kasparov is esteemed by many as the greatest chess player of all time. Now he’s engaged in a game with far higher stakes: the preservation of freedom and democracy.

Johann Hari is the author of two "New York Times" best-selling books.