E.O. Wilson has made a tremendous contribution to our understanding of biodiversity, while his insights on social and group behavior have changed our perception of ourselves. The stirring keynotes from this legendary Harvard biologist are both majestic overtures to all life on earth as well as eloquent pleas to government,...

Karen Armstrong is the most original and inclusive speaker on the role of religion in the modern world. Her bestselling books, including A History of God, and sought-after talks examine the differences and the profound similarities between Christianity, Islam, and Judaism, and their impact on world events.

Susan Cain says our culture holds a decided bias toward the "extrovert ideal" and dramatically undervalues the talents of introverts. No longer. In her bestselling book, Quiet, and in her record-smashing TED talk, Cain shows us how to change the way we work, lead, and teach in order to tap the abundant strengths...

Twenty-two years ago, a truck hit the bus Joshua Prager was riding in Jerusalem, temporarily rendering him, at age 19, a quadriplegic. In powerful and unsentimental talks (including at TED), Prager recounts the long journey that has constituted his life since. His is an emotionally stunning tale—less about the loss...

Steven Pinker asks audacious questions about the human mind—then boldly sets out to answer them. Named one of TIME magazine's 100 Most Influential People in The World, he's a brilliant speaker, is enormously popular in the media and highly respected in scientific circles. And for good reason.

Sal Khan is the founder of the Khan Academy, a nonprofit with the mission of providing free, high-quality education to "anyone, anywhere" in the world. A former hedge fund analyst with degrees from MIT and Harvard, Khan is also the author of The One World School House, which explores the potential impact of the...

The connection between two individuals is a powerful agent for social change. This idea animates the work of Jessica Jackley, who co-founded KIVA, the world's most successful microlending site. On stage, Jackley delivers an upbeat and enduring message: you can synthesize your disparate skills, as she did, to create a meaningful...

Janna Levin is changing the way we understand the cosmos. She brings originality, lucidity—and even poetry—to one of humanity's oldest sciences. On stage, Levin expands on her mind-bending yet concrete ideas: from black holes to creativity, to the union of art and science, Levin shows audiences just how far...

Alex Steffen is the thinking-person's optimist. His inspiring, provocative talks about our future pack houses around the world. Whether explaining humanity's best solutions (in Worldchanging), imagining the opportunities to be found in climate-neutral cities (in Carbon Zero), or sharing breakthrough insights...