Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and Ideas

A weekly Science, Physics and Society podcast featuring
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The internet has made it so much easier for people to talk to each other, in a literal sense. But it hasn’t necessarily made it easier to have rewarding, productive, good-faith conversations. Here I talk with sociologist Rod Graham about what kinds of conversations the internet does enable, and should enable, and how we can work to make them better. We discuss both how social media are used for nefarious purposes, from cyberbullying to driving extremism, but also how they can be mobilized for more lofty goals. We also get into some of the lost nuances in conventional discussions of race, including how many minorities are more culturally conservative than an oversimplified narrative would lead us to believe, and the tricky relationship between online discourse and social cohesion.Support Mindscape on Patreon.Roderick Graham received his Ph.D. in sociology from the City University of New York. He is currently an Associate Professor of Sociology and Criminal Justice at Old Dominion University, and serves as the coordinator of the university’s Cybercriminology Bachelor’s program. He is the author of The Digital Practices of African-Americans.Web siteOld Dominion web pageGoogle Scholar publicationsArticles on MediumYouTube channelTwitter
In July 2018, 12 youth soccer players and their coach found themselves trapped 6 miles deep in a cave with no food or water and depleting oxygen. The rock formed maze became almost completely submerged as the water rose to levels nearly impossible for survival. There was no light and no way to communicate with the outside world. The first season of Wondery’s new original series Against the Odds takes you into the incredible events of when an adventurous group of teens found themselves fighting to save their lives, and the brave heroes that gave them their only chance at survival. With step by step recounts, experience for yourself what it was like to be in their shoes, and how they survived against the odds. Listen to Against the Odds at
In our postmodern world, studying the classics of ancient Greece and Rome can seem quaint at best, downright repressive at worst. (We are talking about works by dead white men, after all.) Do we still have things to learn from classical philosophy, drama, and poetry? Shadi Bartsch offers a vigorous affirmative to this question in two new books coming from different directions. First, she has newly translated the Aeneid, Vergil’s epic poem about the founding myth of Rome, bringing its themes into conversation with the modern era. Second, in the upcoming Plato Goes to China, she explores how a non-Western society interprets classic works of Western philosophy, and what that tells us about each culture.Support Mindscape on Patreon.Shadi Bartsch-Zimmer received her Ph.D. in Classics from the University of California, Berkeley. She is currently the Helen A. Regenstein Distinguished Service Professor of Classics at the University of Chicago. Among her awards are a Guggenheim Fellowship, an American Council of Learned Societies Fellowship, and multiple teaching awards. She has served as the Editor-in-Chief of Classical Philology, and is the Founding Director of the Stevanovich Institute on the Formation of Knowledge. She is developing an upcoming podcast.Web siteUniversity of Chicago web pageWikipediaTwitterAmazon author pageWashington Post Op-Ed
Welcome to the February 2021 Ask Me Anything episode of Mindscape! These are funded by Patreon supporters (who are also the ones asking the questions). This month is in what has been the conventional format, where I just try my best to answer every question. But it’s growing a bit unwieldy, so going forward I might just try to pick my favorite questions and answer them in greater detail. We shall see.Support Mindscape on Patreon.
A common argument against free will is that human behavior is not freely chosen, but rather determined by a number of factors. So what are those factors, anyway? There’s no one better equipped to answer this question than Robert Sapolsky, a leading psychoneurobiologist who has studied human behavior from a variety of angles. In this conversation we follow the path Sapolsky sets out in his bestselling book Behave, where he examines the influences on our behavior from a variety of timescales, from the very short (signals from the amygdala) to the quite ancient (genetic factors tracing back tens of thousands of years and more). It’s a dizzying tour that helps us understand the complexity of human action.Support Mindscape on Patreon.Robert Sapolsky received his Ph.D. in neuroendocrinology from Rockefeller University. He is currently the John and Cynthia Fry Gunn Professor of Biology, Neurology, and Neurosurgery at Stanford University. His awards include a MacArthur Fellowship, the McGovern Award from the American Association for the Advancement of Science, and Wonderfest’s Carl Sagan Prize for Science Popularization.Stanford web pageWikipediaRobert Sapolsky Rocks (fan page)Amazon author pageYouTube lectures on Human Behavioral BiologyIMDb
It’s a truism that what we see about the world is a small fraction of all that exists. At the simplest level of physics and biology, our senses are drastically limited; we only see a narrow spectrum of electromagnetic waves, and we only hear a narrow band of sound. We don’t feel neutrinos or dark matter at all, even as they pass through our bodies, and we can’t perceive microscopic objects. While science can help us overcome some of these limitations, they do shape how we think about the world. Ziya Tong takes this idea and expands it to include the parts of our social and moral worlds that are effectively invisible to us — from where our food comes from to how we decide how wealth is allocated in society.Support Mindscape on Patreon.Ziya Tong received a B.A. in psychology and sociology from the University of British Columbia, and an M.A. in communications from McGill University. She has served as host, writer, director, producer, and reporter from a number of science programs, most notably Daily Planet on Discovery Canada. She is a Trustee of the World Wildlife Fund, and served on the Board of WWF Canada. Her book The Reality Bubble: How Science Reveals the Hidden Truths that Shape Our World was published in 2019.Web siteIMDb pageWWF pageWikipediaAmazon author pageTwitter
Here is a special bonus punishment treat for Mindscape listeners: an interview of me, by David Zierler of the American Institute of Physics’s Oral History project. This is a fantastic project that collects interviews with influential physicists of all ages, and apparently sometimes less-influential physicists. So if you’d like to hear my (academic) life story boiled down to a mere four hours, here you go!Support Mindscape on Patreon.It’s well worth checking out the AIP Oral History Project website, which has over 1000 fascinating interviews with physicists from different decades. The transcript of this particular interview can be found there. Thanks to David and the AIP for letting us include this as a bonus podcast episode.
As a semi-outsider, it’s fun for me to watch as a new era dawns in biology: one that adds ideas from physics, big data, computer science, and information theory to the usual biological toolkit. One of the big areas of study in this burgeoning field is the relationship between the basic bioinformatic building blocks (genes and proteins) to the macroscopic organism that eventually results. That relationship is not a simple one, as we’re discovering. Standard metaphors notwithstanding, an organism is not a machine based on genetic blueprints. I talk with biologist and information scientist Michael Levin about how information and physical constraints come together to make organisms and selves.Support Mindscape on Patreon.Michael Levin received his Ph.D. in genetics from Harvard University. He is currently Distinguished Professor and Vannevar Bush Chair in the Biology department at Tufts University, and serves as director of the Tufts Center for Regenerative and Developmental Biology. His work on left-right asymmetric body structures is on Nature’s list of 100 Milestones of Developmental Biology of the Century.Tufts web siteAllen Center web pageGoogle Scholar publicationsTwitter
The possible existence of technologically advanced extraterrestrial civilizations — not just alien microbes, but cultures as advanced (or much more) than our own — is one of the most provocative questions in modern science. So provocative that it’s difficult to talk about the idea in a rational, dispassionate way; there are those who loudly insist that the probability of advanced alien cultures existing is essentially one, even without direct evidence, and others are so exhausted by overblown claims in popular media that they want to squelch any such talk. Astronomer Avi Loeb thinks we should be taking this possibility seriously, so much so that he suggested that the recent interstellar interloper `Oumuamua might be a spaceship built by aliens. That got him in a lot of trouble. We talk about the trouble, about `Oumuamua, and the attitude scientists should take toward provocative ideas.Support Mindscape on Patreon.Abraham (Avi) Loeb received his Ph.D. in plasma physics from the Hebrew University of Jerusalem. He is currently the Frank B. Baird Jr. professor of science at Harvard University. He served as the Chair of Harvard’s Astronomy department from 2011-2020. He is Director of the Institute for Theory and Computation of the Harvard-Smithsonian Center for Astrophysics, and Founding Director of Harvard’s Black Hole Initiative. He is chair of the Advisory Committee for the Breakthrough Starshot Initiative. His new book is Extraterrestrial: The First Sign of Intelligent Life Beyond Earth.Harvard Astronomy web pageCenter for Astrophysics web pageWikipedia
What is the world made of? How does it behave? These questions, aimed at the most basic level of reality, are the subject of fundamental physics. What counts as fundamental is somewhat contestable, but it includes our best understanding of matter and energy, space and time, and dynamical laws, as well as complex emergent structures and the sweep of the cosmos. Few people are better positioned to talk about fundamental physics than Frank Wilczek, a Nobel Laureate who has made significant contributions to our understanding of the strong interactions, dark matter, black holes, and condensed matter, as well as proposing the existence of time crystals. We talk about what we currently know about fundamental physics, but also the directions in which it is heading, for better and for worse.Support Mindscape on Patreon.Frank Wilczek received his Ph.D. in physics from Princeton University. He is currently the Herman Feshbach professor of physics at the MIT; Founding Director of the T. D. Lee Institute and Chief Scientist at Wilczek Quantum Center, Shanghai Jiao Tong University; Distinguished Professor at Arizona State University; and Professor at Stockholm University. Among his numerous awards are the MacArthur Fellowship, the Nobel Prize in Physics (2004, for asymptotic freedom), membership in the National Academy of Sciences and the American Academy of Arts and Sciences. He is the author of numerous books, most recently Fundamentals: Ten Keys to Reality.Web siteMIT web pageGoogle Scholar publicationsNobel biographyProfile in Quanta magazineWikipediaTwitter
The first full week of 2021 has been action-packed for those of us in the United States of America, for reasons you’re probably aware of, including a riotous mob storming the US Capitol. The situation has spurred me to take the unusual step of doing a solo podcast in response to current events. But never fear, I’m not actually trying to analyze current events for their own sakes. Rather, I’m using them as a jumping-off point for a more general discussion of how democracy is supposed to work and how we can make it better. We’ve talked about related topics recently with Cornel West and David Stasavage, but there are things I wanted to say in my own voice that fit well here. Politics is important everywhere, and it’s a crucial responsibility for those of us who live in societies that aspire to be participatory and democratic. We have to think these things through, and that’s what this podcast is all about.Support Mindscape on Patreon.Apologies to Alexis de Toqueville, who wrote an important book whose name I stole, and who is mentioned nowhere in this episode.
We all know stereotypes about people from different countries; but we also recognize that there really are broad cultural differences between people who grow up in different societies. This raises a challenge when most psychological research is performed on a narrow and unrepresentative slice of the world’s population — a subset that has accurately been labeled as WEIRD (Western, Educated, Industrialized, Rich, and Democratic). Joseph Henrich has argued that focusing on this group has led to systematic biases in how we think about human psychology. In his new book, he proposes a surprising theory for how WEIRD people got that way, based on the Church insisting on the elimination of marriage to relatives. It’s an audacious idea that nudges us to rethink how the WEIRD world came to be.Support Mindscape on Patreon.Joseph Henrich received his Ph.D. in anthropology from UCLA. He is currently Professor and Chair of the Department of Human Evolutionary Biology at Harvard University. Among his awards are a Fulbright scholarship, a Presidential Early Career Award, the Killam Research Prize, and the Wegner Theoretical Innovation Prize. His trade books include The Secret of Our Success: How Culture is Driving Human Evolution, Domesticating Our Species, and Making Us Smart, and the new The WEIRDest People in the World: How the West Became Psychologically Peculiar and Particularly Prosperous.Personal web siteLab web siteHarvard web pageWikipediaAmazon author pageTwitter
Welcome to the third annual Mindscape Holiday Message! Just a chance for me to be a little more chatty and informal than usual, although as it turned out this isn’t all that different from a conventional solo episode. With the difference that what I’m talking about — a phenomenon called “cosmic birefringence” — has played a big part in my personal scientific career, so I get to be a bit autobiographical.Every photon has a direction of polarization, which generally remains fixed as the photon travels through space. Birefringence is an effect by which the polarization rotates rather than staying fixed. It can happen in materials, but generally not in outer space. But there are exotic physics ideas that could cause such a rotation, including the dynamical dark energy candidate known as quintessence. People have put limits on such cosmic birefringence for a while now, but recently there was a claim that there might be a nonzero amount of birefringence visible in the polarization of the cosmic microwave background! Still very tentative, but if this hint turns into real evidence, it would big extremely big news for our understanding of physics and cosmology, possibly helping us pinpoint the nature of dark energy.Show notes, links, transcript:
Many characteristics go into making human beings special — brain size, opposable thumbs, etc. Surely one of the most important is language, and in particular the ability to learn new sounds and use them for communication. Many other species communicate through sound, but only a very few — humans, elephants, bats, cetaceans, and a handful of bird species — learn new sounds in order to do so. Erich Jarvis has been shedding enormous light on the process of vocal learning, by studying birds and comparing them to humans. He argues that there is a particular mental circuit in the brains of parrots (for example) responsible for vocal learning, and that it corresponds to similar circuits in the human brain. This has implications for the development of intelligence and other important human characteristics.Support Mindscape on Patreon.Erich Jarvis received his Ph.D. in Animal Behavior and Molecular Neurobehavior from Rockefeller University. He is currently a professor in the Laboratory of Neurogenetics of Language at Rockefeller and an investigator at the Howard Hughes Medical Institute. Among his many awards are the Alan T. Waterman Award from the National Science Foundation, an American Philosophical Society Award, a Packard Foundation fellowship, an NIH Director’s Pioneer award, Northwestern University’s Distinguished Role Model in Science award, and the Summit Award from the American Society for Association Executives.Web siteRockefeller web pageGoogle Scholar publicationsWikipediaTalk on vocal learning and the brainTwitter
Getting into the swing of things here with monthly Ask Me Anything episodes. If you missed the explanation last month, there is a Patreon page for people who wish to support Mindscape with a small donation per episode. Benefits include a warm feeling, social status, access to ad-free versions of the podcast, and the ability to ask questions once per month, which I answer over the course of a hilariously long podcast. Thanks to the generosity of Patreon supporters, we are now making the fruits of these monthly adventures available on the regular podcast feed.Here is the December 2020 edition. Note that there won’t be a January 2021 edition, as I take a break from podcasting for the holidays. Have a good one everybody!Support Mindscape on Patreon.
Those of us living in democracies tend to take the idea for granted. We forget what an audacious, radical idea it is to put government power into the hands of literally all of the citizens of a country. Where did such an idea come from, and where is it going? Political scientist David Stasavage has written an ambitious history of democracy worldwide, in which he makes a number of unconventional points. The roots of democracy go much further back than we often think; the idea wasn’t invented in Athens, but can be found in a large number of ancient societies. And the resurgence of democracy in Europe wasn’t because that continent was especially advanced, but precisely the opposite. These insights have implications for what the future of democracy has in store.Support Mindscape on Patreon.David Stasavage received his Ph.D. in Government from Harvard University. He is currently Dean for the Social Sciences and the Julius Silver Professor in the Department of Politics at New York University and an Affiliated Professor in NYU’s School of Law. He is a fellow of the American Academy of Arts and Sciences. His most recent book is The Decline and Rise of Democracy: A Global History from Antiquity to Today.Web siteNYU web pageGoogle Scholar publicationsTalk on the history of taxation and fairnessAmazon author pageTwitter
Aristotle conceived of the world in terms of teleological “final causes”; Darwin, or so the story goes, erased purpose and meaning from the world, replacing them with a bloodless scientific algorithm. But should we abandon all talk of meanings and purposes, or instead conceptualize them as emergent rather than fundamental? Philosophers (and former Mindscape guests) Alex Rosenberg and Daniel Dennett recently had an exchange on just this subject, and today we’re going to hear from a working scientist. David Haig is a geneticist and evolutionary biologist who argues that it’s perfectly sensible to perceive meaning as arising through the course of evolution, even if evolution itself is purposeless.Support Mindscape on Patreon.David Haig received his Ph.D. in biology from Macquarie University. He is currently the George Putnam Professor of Organismic and Evolutionary Biology at Harvard University. His research focuses on evolutionary aspects of cooperation, competition, and kinship, including the kinship theory of genomic imprinting. His new book is From Darwin to Derrida: Selfish Genes, Social Selves, and the Meanings of Life.Web siteGoogle Scholar publicationsWikipediaAmazon author pageTalk on cooperative behavior
Time! It doesn’t stop, psychological effects of being under lockdown notwithstanding. How we experience time depends on our situation, but time itself just marches forward. Unless, of course, it’s possible to travel to the past, as countless science-fiction scenarios have depicted. But does that really make sense? Couldn’t we then change the past, even so dramatically that our own existence would never have happened? In this solo podcast I talk about both the physics and fiction of time travel. I point out that it might be allowed by the laws of physics, and explain how that would work, but that we really don’t know. And I try to make sense of some of the less-sensible depictions of cinematic time travel. Coming up with a logical theory that could account for Back to the Future isn’t easy, but podcasting isn’t for the squeamish.Support Mindscape on Patreon.But wait, there’s more! I was contacted by Janna Levin, who we fondly remember from Episode 27. Janna moonlights as Chair and Director of Sciences at Pioneer Works, an institution dedicated to bringing together creative people in art and science. Like the rest of us, they’ve been looking for ways to offer more online content in these pandemic times, so we thought about ways to collaborate. Here’s what they came up with: artist Azikiwe Mohammed has created an animated video backdrop to this podcast episode. The visuals are trippy, colorful, and inspired by (without trying to directly illustrate) what I talk about in the episode. You can check out a brief write-up at the Pioneer Works site, or view the video directly below.
As you have likely heard me mention before, I have an account on Patreon, where people can sign up to donate a dollar or two per episode of Mindscape. In return they get two tangible (if minor) benefits. First, they get to listen to the podcast without any ads. Second, once per month I do an Ask Me Anything episode, where patrons are allowed to ask any question they like, and I do my best to answer as many as I can.Patreon supporters have kindly agreed to let these monthly AMA episodes be released to the general public (though they maintain the right actually ask the questions). I announced that I’d be doing this a while back, but with the cost structure I had with my podcast host it turned out to be prohibitively expensive for me. But now we’ve got that all figured out! So now, and hopefully going forward, these AMAs will be part of the regular podcast feed. They will be released sometime in the middle of each month, not as part of the usual Monday weekly series, so they won’t get numbers of their own.
Emotions are at the same time utterly central to who we are — where would we be without them? — and also seemingly peripheral to the “real” work our brains do, understanding the world and acting within it. Why do we have emotions, anyway? Are they hardwired into the brain? Lisa Feldman Barrett is one of the world’s leading experts in the psychology of emotions, and she emphasizes that they are more constructed and less hard-wired than you might think. How we feel and express emotions can vary from culture to culture or even person to person. It’s better to think of emotions of a link between affective response and our behaviors.Support Mindscape on Patreon.Lisa Feldman Barrett received her Ph.D. in psychology from the University of Waterloo. She is currently the University Distinguished Professor of Psychology and Director of the Interdisciplinary Affective Science Laboratory at Northeastern University. She also holds research appointments at Massachusetts General Hospital (MGH)/Harvard Medical School in the Psychiatric Neuroimaging Program and at the Martinos Center for Biomedical Imaging in the Department of Radiology. Among her many honors are the Award for Distinguished Service in Psychological Science from the American Psychological Association, the Mentor Award for Lifetime Achievement from the Association for Psychological Science, and a Guggenheim Fellowship. She is the author of How Emotions Are Made: The Secret Life of the Brain, and her latest book is Seven and a Half Lessons About the Brain.Web siteLab web pageNortheastern web pageGoogle Scholar profileAmazon author pageTalk on How the Brain Creates EmotionsWikipediaTwitter
Imagine you were locked in a sealed room, with no way to access the outside world but a few screens showing a view of what’s outside. Seems scary and limited, but that’s essentially the situation that our brains find themselves in — locked in our skulls, with only the limited information from a few unreliable sensory modalities to tell them what’s going on inside. Neuroscientist David Eagleman has long been interested in how the brain processes that sensory input, and also how we might train it to learn completely new ways of accessing the outside world, with important ramifications for virtual reality and novel brain/computer interface techniques.Support Mindscape on Patreon.David Eagleman received his Ph.D. in neuroscience from the Baylor College of Medicine. He is currently the CEO of Neosensory, a company that builds sensory-augmentation devices, as well as an adjunct professor at Stanford. His research has involved time perception, synesthesia, and sensory substitution. He is the founder and director of the Center for Science and Law. He is a bestselling author of both fiction and nonfiction. He was the writer and host of the TV show The Brain with David Eagleman, and writer of the Netflix documentary The Creative Brain. His most recent book is Livewired: The Inside Story of the Ever-Changing Brain.Web siteStanford web pageGoogle Scholar publicationsNeosensoryTalk on The Livewired BrainAmazon author pageThe Brain with David Eagleman (PBS)WikipediaTwitter
This episode is published on November 2, 2020, the day before an historic election in the United States. An election that comes amidst growing worries about the future of democratic governance, as well as explicit claims that democracy is intrinsically unfair, inefficient, or ill-suited to the modern world. What better time to take a step back and think about the foundations of democracy? Cornel West is a well-known philosopher and public intellectual who has written extensively about race and class in America. He is also deeply interested in democracy, both in theory and in practice. We talk about what makes democracy worth fighting for, the different traditions that inform it, and the kinds of engagement it demands of its citizens.Support Mindscape on Patreon.Cornel West received his Ph.D. in philosophy from Princeton University. He is currently Professor of the Practice of Public Philosophy at Harvard University as well as Professor Emeritus at Princeton. He is the author of numerous books, including Race Matters and Democracy Matters. He is a frequent guest on the Bill Maher Show, CNN, C-Span, and Democracy Now, appeared in the Matrix trilogy, and has produced three spoken-word albums. He is the co-host, with Tricia Rose, of the Tight Rope podcast.Web siteHarvard web pageIndieBound author pageTalk on Race, Democracy, and the HumanitiesWikipediaTwitter
If someone you love is diagnosed with cancer you want them to get the best treatment from the best doctors. In 2013, patients in Michigan thought Farid Fata was that doctor. Between his prestigious education, years of experience and pleasant bedside manner, Fata was everything you could want in a doctor. But he was not who he appeared to be. From Wondery, this is the story of hundreds of patients in Michigan, a doctor, and a poisonous secret.Laura Beil, returns with a second season of the award-winning series “Dr Death.”Click to listen to Dr. Death Season 2:
Erwin Schrödinger’s famous book What Is Life? highlighted the connections between physics, and thermodynamics in particular, and the nature of living beings. But the exact connections between living organisms and the flow of heat and entropy remains a topic of ongoing research. Jeremy England is a leader in this field, deriving connections between thermodynamic relations and the processes of life. He is also an ordained rabbi who finds resonances between modern science and passages in the Hebrew Bible. We talk about it all, from entropy fluctuation theorems to how scientists should approach religion.Support Mindscape on Patreon.Jeremy England received his Ph.D. in physics from Stanford University. He is currently Senior Director in the Artificial Intelligence/Machine Learning group at GlaxoSmithKline. He has been a Rhodes scholar, a Hertz fellow, and was named one of Forbes‘s “30 Under 30 Rising Stars of Science.” His new book is Every Life is on Fire: How Thermodynamics Explains the Origins of Living Things.Web siteGoogle Scholar publicationsTalk on Non-Equilibrium Statistical Mechanics and LifeAmazon author pageWikipediaTwitter
In the service of seeking truth, there would seem to be value in intellectual diversity, both in keeping ourselves honest and in the possibility of new ideas coming from unexpected quarters. That’s true in the natural sciences, but even more so in the humanities and social sciences, where the right/wrong distinction is sometimes less clear. But academia isn’t always diverse; as an empirical fact, there are a lot more liberals on university faculties than there are conservatives. I talk with Musa al-Gharbi about why this is true — self-selection? discrimination? — the extent to which it’s a real problem, and how we should better think about the value of diverse viewpoints.Support Mindscape on Patreon.Musa al-Gharbi received Masters degrees in philosophy from the University of Arizona and in sociology from Columbia University. He is currently a Paul F. Lazarsfeld Fellow in Sociology at Columbia, and until recently served as the Communications Director for Heterodox Academy. His essays have appeared in outlets such as the New York Times, Wall Street Journal, Washington Post, Atlantic Magazine, Foreign Affairs, Voice of America, and Al-Jazeera.Web siteColumbia web pageEssaysPanel discussion on Populism and Tribalism in American LifeHeterodox AcademyTwitter
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Podcast Details

Created by
Sean Carroll
Podcast Status
Jul 1st, 2018
Latest Episode
Mar 1st, 2021
Release Period
Avg. Episode Length
About 1 hour

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