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 nitty-gritty of how we actually discover it. There's a lot to think about once we take a hard look at...
May 04, 2020•1 hr 36 min•Ep. 95
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 extremely seriously the worry that these motivations and purposes may be dramatically at odds with our ow...
Apr 27, 2020•1 hr 27 min•Ep. 94
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 — and especially how they interact with humans. We talk about the diverse social structures of differ...
Apr 20, 2020•1 hr 2 min•Ep. 93
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 picture. That's why it's so important to search for life elsewhere. Today's guest is Kevin Hand, a plan...
Apr 13, 2020•1 hr 56 min•Ep. 92
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 "self-actualization," the ultimate goal of achieving one's creative capacities. Psychologist Scott Bar...
Apr 06, 2020•1 hr 19 min•Ep. 91
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 science, talks with me about the fraught relationship between scientists and their funding sources throug...
Mar 30, 2020•1 hr 35 min•Ep. 90
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 language shapes the way we think. Lera Boroditsky is one of the world's experts on this phenomenon. S...
Mar 23, 2020•1 hr 29 min•Ep. 89
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 also take a practical turn, talking about what measures (washing hands, social distancing, self-isolati...
Mar 18, 2020•1 hr 21 min
"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 process of learning to walk and breathe on land. We talk about how these major transitions happen — ty...
Mar 16, 2020•1 hr 33 min•Ep. 88
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 of the most highly-cited neuroscientists now living, Friston has proposed that we understand the brai...
Mar 09, 2020•1 hr 30 min•Ep. 87
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 runaway super-powerful artificial intelligence. In response, today's guest Martin Rees and others founded the...
Mar 02, 2020•1 hr 40 min•Ep. 86
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 getting married, to having a child, to going to graduate school — with an eye to deciding how to live i...
Feb 24, 2020•1 hr 14 min•Ep. 85
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 let supply and demand set prices and keep government interference to a minimum, while on the other ...
Feb 17, 2020•1 hr 27 min•Ep. 84
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 share a feature of identity — race, ethnicity, gender, sexuality, and others — find it useful to band to...
Feb 10, 2020•1 hr 39 min•Ep. 83
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 have significant therapeutic potential. But this has gradually been changing, and researchers like Robin ...
Feb 03, 2020•1 hr 18 min•Ep. 82
People have always disagreed about politics, passionately and sometimes even violently. But in certain historical moments these disagreements were distributed without strong correlations, so that any one political party would contain a variety of views. In a representative democracy, that kind of distribution makes it easier to accomplish things. In contrast, today we see strong political polarization: members of any one party tend to line up with each other on a range of issues, and correspondi...
Jan 27, 2020•1 hr 22 min•Ep. 81
Physics is simple; people are complicated. But even people are ultimately physical systems, made of particles and forces that follow the rules of the Core Theory. How do we bridge the gap from one kind of description to another, explaining how someone we know and care about can also be "just" a set of quantum fields obeying impersonal laws? This is a hard question that comes up in a variety of forms — What is the "self"? Do we have free will, the ability to make choices? What are the moral and e...
Jan 20, 2020•1 hr 27 min•Ep. 80
We are all alive, but "life" is something we struggle to understand. How do we distinguish a "living organism" from an emergent dynamical system like a hurricane, or a resource-consuming chemical reaction like a forest fire, or an information-processing system like a laptop computer? There is probably no one crisp set of criteria that delineates life from non-life, but it's worth the exercise to think about what we really mean, especially as the quest to find life outside the confines of the Ear...
Jan 13, 2020•1 hr 23 min•Ep. 79
Wilfrid Sellars described the task of philosophy as explaining how things, in the broadest sense of term, hang together, in the broadest sense of the term. (Substitute "exploring" for "explaining" and you'd have a good mission statement for the Mindscape podcast.) Few modern thinkers have pursued this goal more energetically, creatively, and entertainingly than Daniel Dennett. One of the most respected philosophers of our time, Dennett's work has ranged over topics such as consciousness, artific...
Jan 06, 2020•2 hr 2 min•Ep. 78
Welcome to the second annual Mindscape Holiday Message! No substantive content or deep ideas, just me talking a bit about the state of the podcast and what's on my mind. Since the big event for me in 2019 was the publication of Something Deeply Hidden , I thought it would be fun to talk about the process of writing and selling a popular book. Might be of interest to some of you out there! Mindscape takes off for the holidays, so the next regular episode will be published on Monday January 6. It'...
Dec 22, 2019•1 hr 6 min
In the United States, more than one in five deaths is caused by cancer . The medical community has put enormous resources into fighting this disease, yet its causes and best treatments continue to be a puzzle. Azra Raza has been on both sides of the patient's bed, as she puts it — both as an oncologist and expert in the treatment of Myelodisplastic Syndrome (MDS), and as a wife who lost her husband to cancer. In her new book, The First Cell , she argues that we have placed too much emphasis on t...
Dec 16, 2019•1 hr 22 min•Ep. 77
It's too easy to take laws of nature for granted. Sure, gravity is pulling us toward Earth today; but how do we know it won't be pushing us away tomorrow? We extrapolate from past experience to future expectation, but what allows us to do that? "Humeans" (after David Hume, not a misspelling of "human") think that what exists is just what actually happens in the universe, and the laws are simply convenient summaries of what happens. "Anti-Humeans" think that the laws have an existence of their ow...
Dec 09, 2019•1 hr 26 min•Ep. 76
We've talked a lot recently about the Many Worlds of quantum mechanics. That's one kind of multiverse that physicists often contemplate. There is also the cosmological multiverse, which we talked about with Brian Greene. Today's guest, Max Tegmark, has thought a great deal about both of those ideas, as well as a more ambitious and speculative one: the Mathematical Multiverse, in which we imagine that every mathematical structure is real, and the universe we perceive is just one such mathematical...
Dec 02, 2019•1 hr 12 min•Ep. 75
An infinite number of things happen; we bring structure and meaning to the world by making art and telling stories about it. Every work of literature created by human beings comes out of an historical and cultural context, and drawing connections between art and its context can be illuminating for both. Today's guest, Stephen Greenblatt, is one of the world's most celebrated literary scholars, famous for helping to establish the New Historicism school of criticism, which he also refers to as "cu...
Nov 25, 2019•1 hr 6 min•Ep. 74
Changing technologies have always affected how we produce and enjoy art, and music might be the most obvious example. Radio and recordings made it easy for professional music to be widely disseminated, but created a barrier to its creation. Nowadays computers are helping to reverse that trend, allowing casual users to create slick songs of their own. Not everyone is equally good at it, however; Grimes (who currently goes by c , the symbol for the speed of light) is a wildly successful electronic...
Nov 18, 2019•1 hr 18 min•Ep. 73
Maxwell's Demon is a famous thought experiment in which a mischievous imp uses knowledge of the velocities of gas molecules in a box to decrease the entropy of the gas, which could then be used to do useful work such as pushing a piston. This is a classic example of converting information (what the gas molecules are doing) into work . But of course that kind of phenomenon is much more widespread -- it happens any time a company or organization hires someone in order to take advantage of their kn...
Nov 11, 2019•1 hr 17 min•Ep. 72
The human brain contains roughly 85 billion neurons, wired together in an extraordinarily complex network of interconnected parts. It's hardly surprising that we don't understand the mind and how it works. But do we know enough about our experience of consciousness to suggest that consciousness cannot arise from nothing more than the physical interactions of bits of matter? Panpsychism is the idea that consciousness, or at least some mental aspect, is pervasive in the world, in atoms and rocks a...
Nov 04, 2019•1 hr 35 min•Ep. 71
Cosmologists are always talking excitedly about the Big Bang and all the cool stuff that happened in the 14 billion years between then and now. But what about the future? We don't know for sure, but we know enough about the laws of physics to sketch out several plausible scenarios for what the future of our universe will hold. Katie Mack is a cosmologist who is writing a book about the end of the universe. We talk about the possibilities of a Big Crunch (and potential Big Bounce), a gentle cooli...
Oct 28, 2019•1 hr 23 min•Ep. 70
Like so many technological innovations, the internet is something that burst on the scene and pervaded human life well before we had time to sit down and think through how something like that should work and how it should be organized. In multiple ways — as a blogger, activist, fiction writer, and more — Cory Doctorow has been thinking about how the internet is affecting our lives since the very beginning. He has been especially interested in legal issues surrounding copyright, publishing, and f...
Oct 21, 2019•1 hr 18 min•Ep. 69
Artificial intelligence is better than humans at playing chess or go, but still has trouble holding a conversation or driving a car. A simple way to think about the discrepancy is through the lens of "common sense" — there are features of the world, from the fact that tables are solid to the prediction that a tree won't walk across the street, that humans take for granted but that machines have difficulty learning. Melanie Mitchell is a computer scientist and complexity researcher who has writte...
Oct 14, 2019•1 hr 22 min•Ep. 68
