The Scientists Ep. 4: Carl Sagan's Five Principles

Please join my mailing list here 👉 https://briankeating.com/list to win a meteorite 💥 Brian Keating deep dives into the remarkable life and legacy of Carl Sagan—one of history’s greatest science communicators. In this special episode of "The Scientist," Brian explores how a kid from Brooklyn rose to become the voice of science for a generation, making the universe both vast and intimately personal for millions. This episode blends firsthand accounts, critical biographies, and personal reflections to extract five powerful principles from Sagan’s career—offering insights into how we, too, might inject more wonder, rigor, and responsibility into our own journeys. Whether you’re a scientist, a dreamer, or simply curious about your place in the cosmos, this episode promises an inspiring look at an imperfect but extraordinary man who changed how we see our universe. Key Takeaways: 00:00 Reflections on Carl Sagan's Legacy 03:13 Young Sagan Challenges Venus Theories 07:10 Carl Sagan: Public Engagement Advocate 10:26 Carl Sagan's Influential Responsibility 14:31 "Overview Effect: A Vision for Humanity" 16:59 Embracing Change and Courage in Science 22:13 "Challenging Sagan: Science vs. Optimism" 25:20 Galileo's Earth Observations Legacy 26:21 Demand Evidence, Keep Wondering - Join this channel to get access to perks: https://www.youtube.com/channel/UCmXH_moPhfkqCk6S3b9RWuw/join 📚 Get a copy of my books: Think Like a Nobel Prize Winner, with life changing interviews with 9 Nobel Prizewinners: https://a.co/d/03ezQFu My tell-all cosmic memoir Losing the Nobel Prize: http://amzn.to/2sa5UpA The first-ever audiobook from Galileo: Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican https://a.co/d/iZPi9Un 📺 Watch my most popular videos:📺 Neil Turok https://www.youtube.com/watch?v=Dt5cFLN65fI Frank Wilczek https://youtu.be/3z8RqKMQHe0?sub_confirmation=1 Eric Weinstein vs. Stephen Wolfram https://www.youtube.com/watch?v=OI0AZ4Y4Ip4?sub_confirmation=1 Sir Roger Penrose: https://youtu.be/AMuqyAvX7Wo Sabine Hossenfelder: https://youtu.be/g00ilS6tBvs Avi Loeb: https://youtu.be/N9lUceHsLRw Follow me to ask questions of my guests: 🏄‍♂️ Twitter: https://twitter.com/DrBrianKeating 🔔 Subscribe https://www.youtube.com/DrBrianKeating?sub_confirmation=1 📝 Join my mailing list; just click here http://briankeating.com/list ✍️ Detailed Blog posts here: https://briankeating.com/blog ️ Listen on audio-only platforms: https://briankeating.com/podcast #universe #podcast #briankeating #intotheimpossible #science #astronomy #cosmology #cosmicmicrowavebackground #intotheimpossible #briankeating Learn more about your ad choices. Visit megaphone.fm/adchoices

• 0:14Speaker 00

  This is Brian Keating of The Scientist, a special podcast, a breakaway podcast, under the Into the Impossible brand network. It's a pleasure to be discussing one of the greatest science communicators of all time. There really isn't anybody who compares to Carl, and people have tried. I tried. And it's not an easy thing to do. So we're going to be governing over his life, his work, his snubs, some of his greatest failures, some of his greatest triumphs, and of course, how he was perceived and how we perceive scientists today, thanks in large part due to him. He started a new brand of a science influencer and science podcasters owe

• 0:54Speaker 00

  a great deal of gratitude and a debt of gratitude to him. So today's episode of The Scientist focuses on a boy who got his start in life in the cosmos. 1934, November 9th, in Brooklyn, New York, a five-year-old boy stood transfixed at the World's Fair, staring up at a massive projection of the future. The universe just got a little bit bigger, and that boy would spend the next 62 years of his life making the universe feel both incomprehensibly vast, but also intimately personal to millions of people. Today, we're diving deep into the life and legacy of Carl Sagan, and I'm not just interested in telling you that he wrote Cosmos, or influenced Neil deGrasse Tyson,

• 1:39Speaker 00

  or worked on Voyager. We know that. We're here to extract the principles that made him one of history's most effective scientific minds. And you may wonder, how did a working-class kid from Brooklyn become the voice of science for an entire generation? What specific mental models did he use? And most importantly, what can we steal from his playbook? We'll cover, in particular, a book by Poundstone about him called Carl Sagan. There's a slightly more critical biography of him. I don't think it was really enjoyed by the Sagan family, which I've had the honor, pleasure to talk to, two of whom I've had the honor and pleasure of talking to, his widow, Andrea, and his daughter Sasha, both three, four, five years ago, maybe, when I was just starting the podcast. So it's interesting to come upon this episode.

• 2:25Speaker 00

  Or maybe not interesting, but this primary source for this episode will at least be taken from a positive biography of him, which is Poundstone's book, as I said, A Life in the Cosmos, Carl Sagan, supplemented by some of Carl's own writing. And so I aim to bring you a mix of first and secondhand sources because I think that's the best way to learn the history of these great individual scientists. It's not going to be a comfortable story about a scientific wonderkin who happened to do science on the side. It's about someone who was willing and often was, in fact, not just in principle, hated by his peers for achieving something bigger than what he might have been able to expect as that young kid back in the 1930s.

• 3:09Speaker 00

  Let me start with a number, 600 degrees Fahrenheit. It's 1960, and now a 26-year-old Sagan is a PhD student. He's standing in front of some of the most accomplished astronomers of their generation, and he's telling them something they weren't ready to hear, that the surface of Venus was hot enough to melt lead. The room erupted. Senior scientists were initially cackling in laughter because the accepted wisdom said that Venus was maybe 50 degrees, maybe. Here was this kid, not a professor yet, telling them that they were off by a mere factor of 11x. But here's what separates Sagan from every other grad student with a wild theory. He didn't just guess.

• 3:51Speaker 00

  He built a model based on radio emissions that everyone else had dismissed as an equipment malfunction. The noise, by the way, the word noise comes from the Latin for nausea, which we experimental physicists often would agree with. While they were protecting the reputations of the senior scientists, he was following the data wherever it led him. And it teaches us what I call Sagan's first principle. We know about Feynman's principle, the first principle is you should not fool yourself. The second principle is that you are the easiest person to fool, and the third principle is don't fool Richard Feynman. But Sagan's principle, I would call that calculated audacity. He wasn't brave. Because he didn't understand the risk. He was brave because he'd done the math and reduced the risk. Think about that for a second.

• 4:35Speaker 00

  When's the last time you made a prediction that could end your career before it started? And more importantly, when's the last time you were so certain of your data you'd take that risk? Two years later, NASA's Mariner II confirmed Venus's surface temperature, a whopping 864 degrees Fahrenheit. Sagan was right. He was off by a mere 300 degrees, but what's that between friends? It was even hotter than predicted. But here's the thing, being right almost destroyed him. See, there's something nobody talks about in science. When you're being spectacularly correct, it can mean that everyone else is equally wrong. It doesn't make you popular. It makes you dangerous. It makes you a threat.

• 5:15Speaker 00

  And the same scientist who laughed at his Venus prediction now saw him as an instrument of their own undoing, a true threat. This kid who was making them all look like fools, that's where Sagan's story gets interesting. Because most people, when faced with professional jealousy, do one of two things. They either retreat, become less visible, less bold, or they attack back, becoming bitter, playing politics, railing against gatekeepers and the very system itself. But Sagan did neither. He did something I've only seen a handful of exceptional people do. He expanded. While his peers were writing papers for other scientists, Sagan started writing for the public, for you, for me. He took that gamble, and it would not only define the rest of his career, became a great

• 5:59Speaker 00

  influence on generations of scientists, including me, and possibly including you. He bet that making science accessible to millions was more important than impressing dozens. His Harvard colleagues were appalled. One professor called him a carnival barker. Another said he'd never be taken seriously as a scientist. And in fact, in 1968, when Harvard denied him tenure, the message was clear. Choose. You can be a serious scientist, or you can be a science communicator. You can be a party line teller, or you can be Carl Sagan, but you cannot be both. This is the moment that breaks most people. You've worked your entire life to join the club, and the club rejects you. This is all he had ever dreamed about. He was on his own, cast away, like a star ejected from the gravitational force

• 6:42Speaker 00

  field of its host galaxy. But the way Sagan responded reveals his second principle: turn stigma into strength. Cornell University offered him a position, but Sagan didn't negotiate like someone who'd just been rejected by Harvard. He negotiated like somebody who knew exactly what he was worth. And this is a lesson that all too many scientists don't pay heed to today, especially, I'm afraid to say, women and minorities, who oftentimes just accept the first offer that they're given. But he knew his worth. He told Cornell, "I need resources for what I love. I need resources for public communication, for dissemination." After all, as I always say, although I never heard Carl Sagan, but I do believe he would agree with

• 7:24Speaker 00

  it, that scientists have a moral obligation to share what they learn with the public who pays their salary. Even at Cornell, a private Ivy League school, there's still a tremendous amount of support from NASA, the National Science Foundation, other sources, a funding that comes exclusively thanks to the largesse of you, the taxpayer. Carl Sagan said, "I need the freedom to write books, to appear on television, to engage with the media." His last book, Billions and Billions, makes fun of his own reputation as really portrayed in TV form by none other than the late, great Johnny Carson, who actually coined the term "billions and billions" with a mop wig on his head, imitating Carl Sagan. They had great banter together. Sagan appeared on Johnny Carson, which was bigger than all the biggest

• 8:08Speaker 00

  talk shows. It was like the Joe Rogan Experience times two or three, because everybody watched Johnny Carson. He was like the last thing you saw at night, every night before you went to bed. Whereas, you know, a good deal of people watch Rogan, but not as many as watched Carson in his heyday. And that's when Carl Sagan would shine. See, Sagan saw what others didn't. He understood that science locked in ivory towers was a death sentence. He knew that wonder, real wonder, is contagious, but only if you're willing to share it. And this is where we need to stop and make something crystal clear. Sagan wasn't dumbing down science. I don't like to dumb down science. He was doing something much more difficult. It's easy to dumb down science. It's hard to make absolute scientific rigor while making it irresistible and accessible. It's easy to hide behind jargon.

• 8:54Speaker 00

  But explaining the greenhouse effect on Venus so clearly that a politician or a talk show host can't pretend that they don't understand it, that's damn hard. That brings us to 1983, height of the Cold War. Sagan and four of his colleagues publish a paper that should have stayed in academic journals. It was about nuclear war, or more precisely, the aftermath of nuclear war. And if you've ever heard of nuclear winter, the idea that a nuclear war of atomic thermonuclear devices would trigger a global ice age. He believed the science was solid. Others weren't so sure. The implications politically and even in the media were terrifying. And most scientists would have just published in some obscure journal, gotten 10 citations,

• 9:35Speaker 00

  and moved on, happy to have made their miniscule incremental contribution to the field that they're a member of. Let's let the policymakers figure it out, but that's not his job. But Sagan understood everything was his job. It was something that his colleagues didn't or wouldn't admit. When you discover something that could, quite frankly, end civilization, staying quiet isn't noble. It's negligent. So Sagan did what no serious scientist was supposed to do. He went on TV. He testified before Congress. He flew to Moscow. Moscow, at the height of the Cold War, was a dangerous place, especially for a learned scientist like Sagan. He met with Soviet scientists, colleagues, competitors. His American colleagues were furious.

• 10:17Speaker 00

  He was out there politicizing and popularizing science, grandstanding. A Nobel laureate even called him a propagandist. But here's what I want you to understand. Sagan wasn't playing politics. He was living by his third principle: Responsibility scales with capability. You're the only one who can explain something crucial. Explaining it isn't optional. It's a mandatory obligation. The nuclear winter work changed global nuclear policy. At that time, both Reagan and Gorbachev cited it as an influence in arms reduction techniques. How many academic papers can say they influenced? Public policy between world superpowers that were engaged in a cold war. But again, for his sins, he was nominated for membership in the prestigious National Academy

• 11:02Speaker 00

  of Sciences, the highest honor in American science, really in the world as an organization. The Nobel Prize is more prestigious, but it's not an organization, it's a collection of winners. He was rejected, nominated, rejected, rejected again and again and again. The message was clear. You can change the world, or you can change the club that you're in, but you can't have it both ways. And this is what I meant to say when I said it's not a comfortable story. Because the truth is, Sagan could have had an easier life. He could have stayed in his lane, published in journals, been celebrated by peers. Instead, he chose impact over approval. He chose to be useful over being purely admired, but he had a huge ego, let's be honest. He had a very big ego. And this brings us to 1980.

• 11:45Speaker 00

  PBS approaches Sagan with an insane proposition. They want him to host a 13-part television series about the universe. Now, I'll cover some of Sagan's flaws, foibles, and shortcomings in just a bit, but it's impossible not to talk about the 1980 world-shifting PBS documentary series called Cosmos. PBS approached Sagan with a proposition. They want him to host a 13-part series about the universe. The budget astronomical, the risk catastrophic. If it failed, whatever scientific credibility he had left would be on the line. Sagan's agent begged him not to do it. His colleagues warned him he'd become just another TV personality.

• 12:30Speaker 00

  Think YouTube influencers, popularizers, maybe me included, who knows? Even his friends thought he was making a huge mistake. Cosmos was going to break records throughout the world. It would go on to be the most-watched science program in television history. Six hundred million people across 60 countries. But the numbers don't tell the real story. The real story is in his letters. Thousands of them poured in, from kids who decided to become scientists, from adults who went back to school, from people who said for the first time in their lives, they understood their place in the universe. And this is Sagan's fourth principle, democratic genius. The idea that the deepest truths aren't just for specialists. That wonder isn't something you grow out of.

• 13:13Speaker 00

  You cultivate curiosity throughout your life. But what killed me when researching this is that while he was filming Cosmos, he was changing how society saw itself. He was also going through his second divorce. His wife said he literally couldn't stop working. We'd call a workaholic these days. At dinner, his mind would be on Mars. At his daughter's recital, he'd be calculating orbital mechanics. And this is the part where I'm supposed to warn you about work-life balance, but I'm not going to insult your intelligence. The truth is, the people who change the world and that we cover on the show aren't really balanced. Just as with my intellectual podcaster and least hero, David Senra, the people that he covers, they're not balanced. Frequently, the founders on the Founders Podcast have horrible family lives,

• 13:57Speaker 00

  multiple divorces, children's sperm that don't show up to even bury their parents. Usually a father. And so too, what the scientists will cover, they're obsessed. They need to be obsessed. They have to be obsessed. Is it worth it? Sagan's obsession was specific. He called it the cosmic perspective, the idea that once you truly understand our place in the universe, on the pale blue dots suspended in a sunbeam, as he called it, everything changes. War seems absurd. Hatred seems pointless. The only thing that matters is protecting this tiny world and expanding our understanding. This wasn't philosophy for Sagan. It was strategy. Everything he did, from the Venus prediction to nuclear winter to Cosmos, the series, it all served this single vision.

• 14:39Speaker 00

  Make sure humanity sees its own reflection, looking back on itself from space. Because once you see it, you can't unsee it. Astronauts call it the overview effect, the indelible, unrelenting change in themselves that occurs once they see the planet Earth from space and how miniscule it is and how all the politicians ruin the planet. But not many of us can go to space, at least not yet. Not yet. Maybe Musk's vision will keep us alive and take us to the stars so we can be like Katy Perry, perhaps all of us. Now, we turn somber. For real, it's 1995, January. The winter is approaching. Sagan's 60 years old. He's been fighting bone marrow

• 15:21Speaker 00

  disease for two long years. He knows he's dying. What does he do? He writes faster. Reminds me of Alexander Hamilton. "Why do you write like you're running out of time?" the song goes. His last book, The Demon Haunted World, isn't about space. It's about thinking. It's about Sagan trying to download everything he knows about not knowing and not being fooled. To teach truths in a world full of lies to his young children that he won't get to see grow into old age. He writes about what he calls the baloney detection kit, a set of tools for critical thinking. But really, it's more than that. It's Sagan's fifth and final principle. Skeptical optimism, pessimistic optimism. Question everything, but believe in the potential

• 16:06Speaker 00

  of human beings and humanity itself. Doubt claims, but don't doubt our ability to find the answers. Be critical of ideas, but generous with people. And I think it's quite lovely to think about Carl. He never recanted his atheism as some claim that he did. That's not true. We'll talk about his foibles and failings in just a second. But I wanted to wrap up this segment of the five principles, at least, with that cold winter day at the end of 1996, December 20th. Carl Sagan leaves this earth. He was working on a new book. He had speeches scheduled. He had ideas, so many ideas left to share. But here's what I can't stop thinking about. In his last interview, knowing he was dying, Sagan didn't talk about his accomplishments.

• 16:50Speaker 00

  He talked about what was left to do. He talked about the generation of scientists who would come after him. He's talking about you. So here's my question. What would you change if you knew you had only 62 years? Not 80, 120, as we sometimes wish our fellows? What comfortable lies would you stop telling yourself? What bold scientific... Opinion or prediction would you make? What truth would you insist upon sharing, even if it made you unpopular? Even if it got you kicked out of the clubs that you once wanted in so desperately? Sagan bet on that simple idea that wonder and skepticism could coexist, that you could be rigorous and poetic, that science belonged to everyone, that the cosmic perspective wasn't just for astronomers.

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  It was for anyone brave enough to look up. And he paid for that bet. Boy, he did. He was mocked by peers, rejected by institutions, criticized by people who should have been his champions. But he also had 600 million ravenous people, more than any other scientist ever seen before or since. Even the great Neil deGrasse Tyson will never reach that many people because the media landscape is so much more fragmented. You spend all your time watching the scientist and listening to the scientist podcast. It doesn't leave you time to go off and watch other scientists in the same depth that those 600 million people around the planet watched him. And the world was much smaller back then in 1980, probably about 5 billion people.

• 18:18Speaker 00

  So it was a much larger fraction of the population of Earth that got to see it. And there are millions of people who also engaged and read his books, I among them. And somewhere, right now, a kid is looking up at the stars for the first time, those billions and billions of stars, and feeling that they're part of something vast, beautiful, and worth protecting. Now, now, I said he's not perfect. Nobody's perfect. Although I tell people that are looking for their husbands, I say, do not look for the perfect man because my wife got the last one. But I do want to touch upon some of the imperfections. Of course, of course, can't overlook the challenge, challenges to this perfect vision of Sagan that everyone loves to have. I believe that during the Biden administration on NASA,

• 19:03Speaker 00

  the administrator didn't swear herself in on the Bible. She swore herself in on a copy of one of Carl Sagan's books. I found that embarrassing as a scientist and as a somewhat agnostic individual myself. But I have to point out that Sagan himself was quite naive when it came to theology, as most atheists that I've encountered are, foremost among them, Sam Harris. Complete. Ignorant about religion, at least the Judeo-Christian version, except where he attempts to mock it. Now Dawkins is as well, and I've interviewed both of them, as well as Dan Dennett, the late great Dan Dennett. So I have my bona fides, my chops in debating these people, and I don't take it from a perspective of pure theism. I always call

• 19:43Speaker 00

  myself a devout practicing agnostic. But in the demon-haunted world and in Contact, he reduced complex theological traditions and the meaning of life into primitive superstitions or evil dogmatism that the belief in the supernatural was uniquely capable of having. And that's the false dichotomy. There are many scientists who have religious traditions and can balance the lack of evidence in their choice of religion with their demand for evidence, as Sagan did in rational scientific endeavors. And that neglects, obviously, mystical traditions from Judaism to Christianity, from Maimonides to Thomas Aquinas to Herschel.

• 20:25Speaker 00

  And these need to realize that it's a little bit more sophisticated than Sagan gave. Of course, the evil character, or the most evil character in Contact, spoiler alert, if you haven't seen it, you know, pause it now, but pause the podcast now, but the evil one is a religious fundamentalist who thinks it's going to be bad to go to space and visit this vegan stellar system that Ellie Arway, based on our good friend and past guest Jill Tarter, loosely at least, is based upon. So Sagan's view of God, like many of the atheists, is intentionally simplistic, straw-manned for rhetorical clarity. And so not all religious belief has to be reduced to God of the gaps. And I think this reductive definition, you know, kind of trait that he had misses the richness of non-fundamentalist,

• 21:10Speaker 00

  at least, theology. He also was incredibly sentimental when it came to the point and teleology of the universe without a God. He said, "If we're alone in the universe, it sure seems like an awful waste of space." Now, this is just sappiness dressed up as logic. The cosmos owes us no company, no purpose, no symmetry. Especially without a divine being. So his lines, while poetic, they import a kind of smuggled theological bias into a universe that, as Camus put it, is unreasonably silent. It's an emotional appeal. It's not a scientific inference. Vastness isn't waste. It's data, and a good scientist like him should have known. Next, the four principles, five principles, I have to have five counterpoints. Otherwise, people accuse me of not being balanced.

• 21:54Speaker 00

  His optimism, again, bordered on naivete. His science and civilization thoughts were inspiring, but they could feel blind to history's darker patterns, from eugenicists to climate science. It's not immune. Science itself is not immune to misuse. The greatest country in terms of scientific output in the 1900s was Germany. The greatest reliance on university education was Germany, and look what that produced. So, over-indexing on the potential of life, intelligent life, including ours, and underplaying the ability and propensity to destroy itself was a hallmark of his career, until he wrote A Pale Blue Dot, which was really just a speech, and it was then turned into a book, one of his 30 books that he either wrote or co-wrote.

• 22:35Speaker 00

  So optimism can be earned through history, but you shouldn't assume it's naturally going to occur through evolution. That's my principle number three. So the anti-Sagan principle, it's not really anti, it's his counterpoint to Carl's counterpoint. Science became somewhat of a religion to him. It was replaced in his ideas of what religion could be, oversimplified and strawmanned, with science as a pure source of wonder, which is fine, curiosity, which is wonderful, but not ethics and not meaning. Science has nothing to say about it. Science means knowledge in Latin. It doesn't mean wisdom. For wisdom, you need experience. And from experience, you need to have judgment, to winnow away the good experience to the

• 23:18Speaker 00

  bad experience, to have good judgment, and to know when wisdom is necessary to make decisions, not to worship, as he seemed to do, the sort of high priests and priestesses of past history, of the history of science. So canonization of skeptical inquiry. That he would typically show, you know, and sometimes veer into a form of almost dogmatic orthodoxy itself. And that, to me, leaves squeezing out the rhetorical room for the metaphysical and bordering on the worship of science itself, and what I call scientism. So let's not confuse the two and conflate the two. They are two separate

• 23:59Speaker 00

  things. And lastly, he was certainly respected by many of his peers, but not all of them, and many of them who would play a role in the public discourse that did criticize him from the highest levels of scientific acumen, shall we say, Steven Weinberg among them, Edward Teller and others, did criticize him, his science, for not being as technically sophisticated or as important to the canon of science. Now, Weinberg, you could, you know, kind of say him, that he didn't have a particular axe to grind. Maybe he did. Maybe he was jealous of Sagan's fame, but I doubt it. He had a Nobel Prize, and Sagan never did. But his snubbing and rejection from the National Academy of Sciences reflected

• 24:43Speaker 00

  this tension that most of his peers did, in fact, not respect him, or were to consume by their own hatred and jealousy of him. We'll never know the truth. These things tend to be sealed for decades. For what reason? I don't know, to protect the guilty, maybe. But I want to finish with kind of where we started, which is this notion of Sagan as a kind of preternatural boy genius that never lost the curiosity of that young boy in Brooklyn. And that's his real legacy. There's no way to diminish that light. Not his discoveries, though they were important and significant. Some of them are incredibly readable and enjoyable to this day. He actually convinced a voyage to Jupiter to turn around and take

• 25:26Speaker 00

  pictures of the Earth on its way out to Jupiter and slingshoting around the sun, and then looked to see if it could detect signs of life as if Earth were an exoplanet. And he comments in the paper about the strange, you know, narrowband radio signals, and those are, of course, coming from radio and television stations, but also a green infrared hue, sorry, red infrared hue, which is coming from a photosynthesis that's occurring on the planet. So he kind of intelligently, uniquely, creatively used a spacecraft, the Galileo spacecraft. To uh, to turn its cameras back on the earth, to look at us. And that's part of his legacy too. Not just the books or the TV series or the interviews on Johnny Carson. It was the permission that he gave us. He was sort of accessible.

• 26:10Speaker 00

  He was the first really accessible scientist that achieved worldwide massive fame. And he taught us famously claiming, although I hate this phrase, that extraordinary claims require extraordinary evidence. Because I don't have a special drawer where I keep my extraordinary evidence. I just pull out the evidence and I use it whenever I have it. You know, here's my piece of alien spacecraft that I found in my kid's underwear drawer. And I'm not going to say that this piece came from aliens, but maybe it did come from aliens. But to refute it, I don't bring out the extraordinary evidence. I bring out evidence. But anyway, that's a minor quip. You probably don't agree with what, with that sentiment. But demand evidence, never stop wondering and to be intellectually and emotionally rigorous.

• 26:53Speaker 00

  And that will help us to expand and explore into the cosmos we're desperately trying to understand. Those are the principles of Carl Sagan. And this has been The Scientist.

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