Biz Stone

Co-Founder of Twitter

Jeremy Rifkin

Leading Global Technologist, Futurist, Authority on World Economic & Environmental Trends

Nastia Liukin

Olympic Gold Medal Gymnast

Mayim Bialik

Neuroscientist, Mental Health Advocate & Actress Known for "The Big Bang Theory"

Dan Ariely

Behavioral Economist; Professor at Duke University; Author; Founding Member of The Center for Advanced Hindsight

Maria Menounos

CEO & Co-founder of AfterBuzz TV; Former E! News Co-Anchor; Best-selling Author, Journalist & Type-1 Diabetic

Lisa Oz

Best-Selling Author, Producer, Host & Entrepreneur

Diana Nyad

World Champion Swimmer, Storyteller, Sports Journalist & Broadcaster

Gabrielle Bernstein

Founder of HerFuture.com & New-York Times Best-Selling Author

Sean Astin

Actor, Director, Voice Artist & Producer Known For "Lord of the Rings"

Mike Walsh

CEO of Tomorrow, Futurist & Best-Selling Author of "The Algorithmic Leader"

John Mackey

Co-Founder & CEO, Whole Foods Market

Gloria Steinem

Feminist Writer, Activist & Organizer; Co-Founder of New York Magazine & Ms. Magazine

Hoda Kotb

Award-Winning Broadcast Journalist, Television Personality, Author & Co-Anchor of NBC News' TODAY

Laila Ali

Undefeated Four-Time World Champion Boxer & Lifestyle Expert; Heart Disease Awareness Advocate

Christy Turlington Burns

Model & Founder of Every Mother Counts; Anti-Smoking Activist

Chris Powell

Trainer and Transformation Specialist on ABC's "Extreme Makeover: Weight Loss Edition"

Richard Thaler

Professor of Behavioral Science and Economics at the University of Chicago; Author of "Misbehaving: The Making of Behavioral Economics"

Richard Thaler: 'We Are Incapable of Learning From the Past ...

Wil Wheaton

Actor, Author & Blogger; Known for "Star Trek: The Next Generation" & "The Big Bang Theory"

Jesse Tyler Ferguson

Actor & LGBTQ Activist; Best-Known for “Modern Family”