Bill Nye

"The Science Guy"; Science Communicator, TV Presenter & Mechanical Engineer; Climate Change Activist

Lisa Ling

Award-Winning Journalist & Producer for CBS News

Tensie Whelan

Director of NYU's Center for Sustainable Business; Former President of the Rainforest Alliance

Sophia Bush

Actress, Humanitarian & Author

Walter Robb

Food Retail Expert & Food Access Advocate; Principal at Stonewall Robb Advisors; Former Co-CEO of Whole Foods Market

Jason Clay

Senior Vice President of Food & Markets at WWF

Caroline Casey

Founder of Kanchi & The Ability Awards

Mark Lynas

Environmental Writer; Author of "Our Final Warning: Six Degrees of Climate Emergency"

Alexis Ohanian

Co-Founder of Initialized Capital & Co-Founder of Reddit; Entrepreneur, Investor, Activist & Bestselling Author

Alexis Ohanian Carthage College Commencement Address 2014

Ahmed Hassan

Celebrity Landscaper & TV Host of DIY's Yard Crashers, Blog Cabin, Turf War

Ian Somerhalder

Actor Known for "The Vampire Diaries"; Animal & Environmental Advocate; Founder of The Ian Somerhalder Foundation

John Ratzenberger

Emmy-Nominated Actor, Entrepreneur & Philanthropist

Amory Lovins

Co-Founder & Chairman Emeritus of Rocky Mountain Institute

Winona LaDuke

Executive Director of Honor the Earth

Ray Kurzweil

Chairman of Kurzweil Technologies, Inventor & Futurist; Author of "How to Create a Mind"

Daniel Kraft, M.D.

Physician-Scientist; Founder of Exponential Medicine; Chair for Medicine & Neuroscience at Singularity University

Dr. Michio Kaku

World-Renowned Futurist & Theoretical Physicist

Ashley Judd

Actress, Activist & Humanitarian

Geoffrey West

Theoretical Physicist, Distinguished Professor & Past President of Santa Fe Institute

Gary Snyder

Pulitzer Prize-Winning Poet, Essayist, Lecturer & Environmental Activist