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

We gather empirical evidence about the nature of the world through our senses, and use that evidence to construct an image of the world in our minds. But not all senses are created equal; in practice, we tend to privilege vision, with hearing perhaps a close second. Ann-Sophie Barwich wants to argue that we should take smell more seriously, and that doing so will give us new insights into how the...

Creativity is one of those things that we all admire but struggle to define or make concrete. Music provides a useful laboratory in which to examine what creativity is all about — how do people become creative, what is happening in their brains during the creative process, and what kinds of creativity does the audience actually enjoy? David Rosen and Scott Miles are both neuroscientists and musici...

Cooking is art, but it's also very much science — mostly chemistry, but with important contributions from physics and biology. (Almost like a well-balanced recipe…) And I can't think of anyone better to talk to about the intersection of these fields than Kenji López-Alt: professional chef and restauranteur, MIT graduate, and author of  The Food Lab . We discuss how modern scientific ideas can impr...

The best chess and Go players in the world aren't human beings any more; they're artificially-intelligent computer programs. But the best poker players are still humans. Poker is a laboratory for understanding how rationality works in real-world situations: it features stochastic events, incomplete information, Bayesian updating, game theory, reading other people, a battle between emotions and rea...

I recently saw an estimate that if you took all the novel coronaviruses in the world (the actual viruses, not patients), you could fit them into a bucket no more than a couple of liters in volume. A huge impact has been wrought by a very small amount of stuff. The world of viruses is vast and complicated, and we're still learning some of its basic features. Today's guest David Baltimore won the No...

A podcast only hits the century mark once! And for Mindscape, this is it. There have been holiday messages and bonus episodes and the like. But this is the 100th officially-numbered episode. To celebrate, I decided to treat myself to a solo episode in which I reflect, somewhat non-systematically, on the age-old question of the meaning of life. I end up spending a lot (most?) of the time talking ab...

There are some problems for which it's very hard to find the answer, but very easy to check the answer if someone gives it to you. At least, we think there are such problems; whether or not they really exist is the famous  P vs NP problem , and actually proving it will win you  a million dollars . This kind of question falls under the rubric of "computational complexity theory," which formalizes h...

Each of us is different, in some way or another, from every other person. But some are more different than others — and the rest of the world never stops letting them know. Societies set up "norms" that define what constitute acceptable standards of behavior, appearance, and even belief. But there will always be those who find themselves, intentionally or not, in violation of those norms — people...

Humans build machines, in part, to relieve themselves from the burden of work on difficult, repetitive tasks. And yet, despite the fact that machines are everywhere, most of us are still working pretty hard. But maybe that's about to change. Futurists like John Danaher believe that society is finally on the brink of making a transition to a world in which work would be optional, rather than mandat...

The past few centuries of scientific progress have displaced humanity from the center of it all: the Earth is not at the middle of the Solar System, the Sun is but one star in a large galaxy, there are trillions of galaxies, and so on. Now we know that we're not even made of the same stuff as most of the universe; for every amount of ordinary atoms and other known particles, there is five times as...

Everybody talks about the truth, but nobody does anything about it. And to be honest, how we talk about truth — what it is, and how to get there — can be a little sloppy at times. Philosophy to the rescue! I had a very ambitious conversation with Liam Kofi Bright, starting with what we mean by "truth" (correspondence, coherence, pragmatist, and deflationary approaches), and then getting into the n...

Artificial intelligence has made great strides of late, in areas as diverse as playing Go and recognizing pictures of dogs. We still seem to be a ways away from AI that is "intelligent" in the human sense, but it might not be too long before we have to start thinking seriously about the "motivations" and "purposes" of artificial agents. Stuart Russell is a longtime expert in AI, and he takes extre...

Human beings have a strange fascination with dangerous, predatory animals — bears, lions, wolves, sharks, and more. The top of the food chain is an interesting and precarious place to live; while you might be the boss of your local environment, you also depend on the functioning of an entire ecology. Rae Wynn-Grant is a carnivore ecologist who studies how large predators migrate, feed, reproduce —...

It's hard doing science when you only have one data point, especially when that data point is subject to an enormous selection bias. That's the situation faced by people studying the nature and prevalence of life in the universe. The only biosphere we know about is our own, and our knowing anything at all is predicated on its existence, so it's unclear how much it can teach us about the bigger pic...

If one of the ambitious goals of philosophy is to determine the meaning of life, one of the ambitious goals of psychology is to tell us how to achieve it. An influential work in this direction was  Abraham Maslow's hierarchy of needs  — a list of human needs, often displayed suggestively in the form of a pyramid, ranging from the most basic (food and shelter) to the most refined. At the top lurks...

Science costs money. And for a brief, glorious period between the start of the Manhattan Project in 1939 and the cancellation of the Superconducting Super Collider in 1993, physics was awash in it, largely sustained by the Cold War. Things are now different, as physics — and science more broadly — has entered a funding crunch. David Kaiser, who is both a working physicist and an historian of scien...

What direction does time point in? None, really, although some people might subconsciously put the past on the left and the future on the right, or the past behind themselves and the future in front, or many other possible orientations. What feels natural to you depends in large degree on the native language you speak, and how it talks about time. This is a clue to a more general phenomenon, how l...

This is a special episode of Mindscape, thrown together quickly. Many thanks to Tara Smith for joining me on short notice. Tara is an epidemiologist, and a great person to talk to about the novel coronavirus (and its associated disease, COVID-19) pandemic currently threatening the world. We talk about what viruses are, how they spread, and a lot of the science behind virology and pandemics. We als...

"What good is half a wing?" That's the rhetorical question often asked by people who have trouble accepting Darwin's theory of evolution by natural selection. Of course it's a very answerable question, but figuring out what exactly the answer is leads us to some fascinating biology. Neil Shubin should know: he is the co-discoverer of  Tiktaalik Roseae , an ancient species of fish that was in the p...

If you tell me that one of the world's leading neuroscientists has developed a theory of how the brain works that also has implications for the origin and nature of life more broadly, and uses concepts of entropy and information in a central way — well, you know I'm going to be all over that. So it's my great pleasure to present this conversation with Karl Friston, who has done exactly that. One o...

Anyone who has read histories of the Cold War, including the  Cuban Missile Crisis  and the  1983 nuclear false alarm,  must be struck by how incredibly close humanity has come to wreaking incredible destruction on itself. Nuclear war was the first technology humans created that was truly capable of causing such harm, but the list of potential threats is growing, from artificial pandemics to runaw...

It's hard to make decisions that will change your life. It's even harder to make a decision if you know that the outcome could change  who you are . Our preferences are determined by who we are, and they might be quite different after a decision is made — and there's no rational way of taking that into account. Philosopher L.A. Paul has been investigating these transformative experiences — from ge...

Nations generally want their economies to be rich, robust, and growing. But it's also important to person to ensure that wealth doesn't flow only to a few people, but rather that as many people as possible can enjoy the benefits of a healthy economy. As is well known, the best way to balance these interests is a contentious subject. On one side we might find free-market fundamentalists who want to...

The Greek statesman Demosthenes is credited with saying "I am a citizen of the world," and the idea that we should take a cosmopolitan view of our common humanity is a compelling one. Not everyone agrees, however; in the words of former British Prime Minister Theresa May, "If you are a citizen of the world, you are a citizen of nowhere." On the other side of the political spectrum, groups who shar...

The  Convention on Psychotropic Substances  was a 1971 United Nations treaty that placed strong restrictions on the use of psychedelic drugs — not only on personal use, but medical and scientific research as well. Along with restrictions placed by individual nations, it has been very difficult for scientists to study the effects of psychedelics on the brain, despite indications that they might hav...