What Happens When We All Know? | Brian Greene & Steven Pinker

How do humans understand each other, cooperate, and build civilizations? Brian Greene sits down with Harvard cognitive scientist Steven Pinker — author of the newly released When Everyone Knows That Everybody Knows — for a deep dive into the psychology of common knowledge, the evolution of language, and the invisible rules that make society possible. They explore why we laugh, cry, and signal emotions, how shared understanding and social norms hold civilization together, and what happens when those norms break down. The conversation also tackles AI vs human intelligence, misinformation, and whether shared truth can survive in a fragmented digital world. This program is part of the Rethinking Reality series, supported by the John Templeton Foundation. Participant: Steven Pinker Moderator: Brian Greene #worldsciencefestival #briangreene #cosmology #astrophysics Don't miss a video! Subscribe NOW: https://www.youtube.com/worldsciencef... ABOUT WORLD SCIENCE FESTIVAL: The World Science Festival (WSF) is a multimedia organization bringing the most transformative ideas in science to global audiences. Through long- and short-form videos spanning physics, cosmology, quantum mechanics, biology, neuroscience, consciousness, medicine, space exploration, the dilemma of free will, artificial intelligence, engineering, robotics, and beyond. WSF gathers world-renowned scientists, artists, and thinkers for dynamic discussions, debates, lectures, performances, films, and immersive live experiences. Founded in 2008 and headquartered in New York City, the World Science Festival is a production of the World Science Foundation, a 501(c)(3) nonprofit organization. Our mission is to cultivate a public informed by science, inspired by its wonder, convinced of its value, and prepared to engage with its implications for the future. With live events reaching millions worldwide and hundreds of millions of digital views, WSF continues to expand its global impact through festivals, educational initiatives like World Science U, and digital content that explores the near and far future of our world. FOLLOW WORLD SCIENCE FESTIVAL: Website: https://worldsciencefestival.com/ Instagram: Instagram: worldscifest TikTok: TikTok: worldscifest X(Twitter): Twitter: worldscifest Facebook: Facebook: worldsciencefestival LinkedIn: LinkedIn: world-science-festival Chapters: 0:00:00 Introduction: Steven Pinker on Language, Mind, and Human Nature 0:00:44 The Monty Hall Puzzle and the Power of Common Knowledge 0:07:39 How Shared Understanding Helped Humans Thrive 0:21:08 The Origins of Language: Daniel Dor’s “Instructing the Imagination” 0:25:17 Pinker vs. Chomsky: Where Language and Thought Diverge 0:29:39 Common Knowledge and the Hidden Logic of Social Norms 0:34:18 When Norms Break: The Psychology Behind Modern Politics 0:40:32 The Architecture of Communication: How We Exchange Ideas 0:42:43 The Metaphor That Drives Civilization 0:48:25 Institutions, Bias, and the Fragility of Collective Truth 0:53:06 Artificial Intelligence and the Evolution of Understanding 0:58:34 Consciousness, Language, and the Limits of Machines 1:01:03 Can We Ever Test for Consciousness? 1:02:43 What AI Reveals About the Human Mind 1:06:03 Credits What Happens When We All Know? | Brian Greene & Steven Pinker @worldsciencefestival