Holiday Message 2022 | Thinking Really Slowly

0:00:00.6 Sean Carroll: Hello everyone, welcome to the Mindscape Podcast. I'm your host Sean Carroll, and this is our annual holiday message for 2022. It's a rainy day here in Baltimore, my first December here in Baltimore, so if you hear little pitter-patter of raindrops on the window right next to me, that's why. Something we didn't get too much of in LA. You know, the idea behind the holiday message that I started doing in the first year of the podcast would be a solo episode, but something shorter, you know, not structured, not deep, not careful. More like a little reflective, self-indulgent perhaps, more personal, set of opinions about, I don't know, something that was inspired by the year that had just passed, whether it was with the podcast or the outside world or whatever is going on in my life. And I've not been great about picking topics. I mean, I think the actual holiday message has been pretty good, but I really need to sit down and think every single year about what to talk about.

0:00:56.4 SC: So, this year, I did think of a couple things. You know, obviously, my life has been completely uprooted, moving from LA and Caltech to Baltimore and Johns Hopkins. Still haven't yet moved into the house that we will eventually move into, but that's coming later this week, so apologies if this is a quick and dirty kind of episode. But there were two things that I kept thinking about that certainly did not rise to the level of a whole episode, and I realized there was a through line through them that I could combine together. And the two things were, on the one hand, things going on online and in the tech world, and subset of that, number one, Twitter, obviously being bought by Elon Musk, changing in various ways. I'm very active on Twitter, so that is affecting me. And the other one was the FTX crypto collapse featuring Sam Bankman-Fried, about which I'm certainly no expert, but nevertheless have some opinions about. So that's something that I wanted to say something about in a very narrow specific way. I have no way of commenting on the bigger picture there.

0:02:05.0 SC: The other idea was, again, coming to Johns Hopkins and being now a professor both in the physics department and the philosophy department, concentrating on foundations of physics, the idea that in some sense what separates foundations of physics from just regular physics research is a certain kind of patience, a certain kind of value in thinking slowly and carefully about things. You know, physicists, in some sense are always thinking carefully about something, but they take some things they don't need to think carefully about and put them in a little box and don't worry about it. And in foundations of physics, we really wanna open precisely those boxes and dig into them. And the common thread here is, of course, precisely that value of thinking slowly. I think that in the small number of things I have to say about Twitter and FTX, they mostly centre around, you know, boy, people are really over valorizing not thinking very carefully before doing something and then watching as the consequences blow up in their faces.

0:03:08.3 SC: So in some sense both of these things, this sort of online set of kerfuffles and the difference between ordinary everyday physics research and foundations of physics comes down to an appreciation for thinking slowly and carefully. So, the title of course, blatantly stolen from Daniel Kahneman's famous book, Thinking, Fast and Slow, he's talking psychologically about system one thinking, which is sort of all of our beneath the surface subconscious heuristic ways of thinking about the world; thinking fast, ways that we already have patterns for, you know, when you're driving to work, if you commute in the same way every day, you're more or less on autopilot, right? You know, the difference between playing guitar or playing a sport as an expert who it's all sort of automatic and you're in the flow zone versus someone who's overthinking things like that. And then, system two is the cognitive part of your brain doing math problems, writing text or something like that, where you really have to sit and think carefully about it.

0:04:10.6 SC: But I wanna sort of... I'm just joking about the title by going further than that to thinking really slowly. Not just being cognitive and doing a math problem, but taking a breath, thinking about the context that some certain problem or situation resides in and thinking about all of the connotations and insinuations and implications of what is going on. Now, in part, this is kind of a cheap point to make. I'm not claiming that it is any way profound. I suspect that most Mindscape listeners, by virtue of a very strong selection effect on whether or not you listen to Mindscape, are already convinced that thinking carefully and slowly about things is a good thing. But maybe by looking at some particular examples we can flesh that out a bit.

0:04:58.1 SC: And I do wanna stand up for the fact that the people who don't always sit back and think very carefully about things aren't necessarily making mistakes. There are usually reasons for doing it that way. And so, it's important to sort of separate out the conditions under which moving fasting and breaking things, which is the Silicon Valley motto, is the right thing to do versus stepping back and kind of trying to be more careful in the China shop. So that's what we're gonna be doing here today. And I think that's it. Holiday Message 2022. Happy holidays to everyone out there and let's go.

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0:05:50.9 SC: I think perhaps of all the podcast episodes I've done here at Mindscape, so well over 200 now, the one that I keep quoting the most or coming back to the most is the one with Thi Nguyen on the philosophy of games and gamification. That one really stuck with me, really sort of shaped how I think about things. So, you keep hearing me refer back to it. And part of that was because, you know, I think that games are intrinsically interesting and certainly a huge part of modern human life, gamification is something very much to worry about. But Thi really extended it, like a good philosopher should, into a realm way beyond what you might guess it would attach to. He really emphasized the allure of clarity and simplicity in worldviews and models of the world.

0:06:39.2 SC: And you know, I think if you had asked me before that podcast about how important clarity and simplicity are in a good model of the world, I would have been very much in favour of them and still am in some way. But what Thi was really emphasizing was, there is a downside, there's a dark side to clarity in your view of the world. Trying to get things to be too clear and too simple is seductive, because it makes you think you have answers for everything. And that opens you up to vulnerability, to being a conspiracy theorist, to generally disdaining, questioning yourself, adding new nuance and carefulness into your way of viewing the world. And that can make you fall into a trap, that can limit the ways in which you think about and experience of the world. So, like many ways, going back to Aristotle, there's a happy medium maybe here to be struck between looking for simplicity and clarity, but not thinking you have it before you really do. That's the difficult thing to do. So, that's sort of the lens with which I wanna think about these things I'm talking about. You know, are people oversimplifying the world for some purportedly sensible purpose and then having it backfire on them?

0:07:55.0 SC: So, the first example is the purchase of Twitter by Elon Musk. And again, there's much to say about this and I'm not gonna in any sense give any comprehensive response or set of thoughts to it. It's just not something that I've thought about systematically in any way. So it would kind of be a little hypocritical of me to, you know, pretend to have the complete theory of that when I haven't thought about it systematically, since my whole message is the value, virtue of thinking systematically, at least, the message in this particular holiday message.

0:08:26.7 SC: But you know, it's been a mess, honestly, right? I am not in favour of the changes at Twitter since Elon bought it. There's a great increase in juvenile trolling including by the new owner, ugly interactions, lack of moderation, lack of direction for the company, and so on. Enough so that I personally have down-shifted my own Twitter use. You know, I'm not abandoning it yet. I don't think that any of the currently existing alternatives are comprehensive alternatives. Maybe they will grow into it. I actually am not gonna pretend to be able to predict the future about Twitter. Something like Twitter is really, really useful. I've made friends. I've learned a lot. But it's also kind of a mess in many, many ways. So, I'm spending less time on social media in general. And you know, this is part of just a general thought that, you know, you have only a finite number of hours in the day, only three billion heartbeats in your lifetime, how are you going to spend them?

0:09:25.3 SC: I did, just as an example, put up a joke on Twitter right after Elon had bought it and people were complaining that it was going to crash and things like that. And I said, "Well, you know, maybe it would just be a good thing if we took the year off and read some books." And because it's Twitter, [chuckle] people immediately misinterpreted it in an uncharitable way as we should quit our jobs and do nothing but read books, when really, I was just talking about switching off social media and reading books instead. And therefore, I was criticized for being too bourgeois and wealthy and not understanding people's real lives and the whole bit. This is part of the problem with a Twitter-like conversation system. But the point being that, you know, there is a time and place for quick hit reactions, for instantaneous takes or whatever. And there's also a time and place for getting deep into something. And maybe we've lost the balance there a little bit.

0:10:20.2 SC: And so, rather than giving a comprehensive response to the new regime at Twitter, I do wanna just focus in on this idea that Elon or whoever is helping him have just been way too simplistic about how this should and does work. This is shown in, you know, they released a whole bunch of text messages that Elon had been sending about the Twitter acquisition before it actually happened. One of which was from some CEO who says, "Step one: Solve free speech." I'm not making this up. [chuckle] So, you know, that just reveals so much. Just that... No, I mean, maybe it was not meant to be entirely serious, but the idea that it is not simply parodying something, but at least, you know, meant to be pointing in the correct direction is just so absurd to me. And it pains me deeply, 'cause I think that the issue of free speech is super-duper important. Not... And I mean that both because I think that free speech is important, but also, what restrictions we should have on free speech and in which context we should have them is super difficult.

0:11:28.1 SC: This is exactly an issue that requires really, really carefully thinking about it, because it's not an absolutist yes or no thing. It is a quintessential example of balancing different kinds of values and different kinds of goals, and that's always gonna be tricky. You always have to sit down and think about it carefully. Just listen to the podcast I did a few years ago with Teresa Bejan about the history of it and, you know, the modern version of it. And Teresa is someone who is a free speech scholar and has thought about it a lot and she will admit and did it a bit on the podcast, you know, she started off pretty hardcore about being a free speech absolutist, but has seen her thinking on that sort of become more nuanced and careful as you think about it. And what I see happening online is that the phrase "free speech" is sort of degenerating from a crucially important political, philosophical concept into a slogan. It becomes a tribal identifier, right? You know, are you in favour of free speech or are you in favour of suppression of alternate ideas 'cause you can't handle the truth? And that's the level of simplicity that the conversation is degenerating into.

0:12:41.8 SC: Same thing with words like "woke" or "politically correct" or whatever. They become slogans by people who wanted to make a point with them and use them for political advantage. And that makes it harder no matter what you might think about it, no matter which side you're on about any of these issues, it makes it harder to have a careful conversation, because people want to load on a bunch of connotations for political purposes to these existing phrases. And so, free speech is becoming like that. And everyone knows, when Elon Musk bought Twitter, he came in saying, "Comedy is now allowed on Twitter, free speech has returned," etcetera, etcetera. "We're not gonna do anything except obey the law. So, if something is illegal, we're gonna get rid of it, and if something is not, we're gonna leave it on."

0:13:25.5 SC: Turns out, it's trickier than that. [chuckle] It turns out that that's a hard thing to do. Even if you just did that, there's different countries with different laws. It turns out to be really difficult even to implement that way over simplistic version of a moderation policy. And people wrote about this. And I'm sorry I forget the names and the ability to therefore cite them, but as soon as it happened, the purchase, you know, people who were very, very experienced in this field, basically wrote articles saying, "Here's how it's gonna go." [chuckle] You're gonna say, "Oh, you can do whatever you want on Twitter, it's completely free speech." And then someone's gonna say, "Well, what about death threats?" You can go, "Oh no. Okay, no death threats." "Well, what about hardcore pornography?" "Well, no hardcore pornography."

0:14:08.9 SC: And then what you realize very, very quickly is, you are drawing a line. Everyone draws a line between what is permitted and what is not permitted. I mean, there was just an example literally today as I'm recording this, where Elon famously said that he is such a big believer in free speech that he would not disturb the Twitter account of the guy who tracks his private plane. Guess what? He just got rid of the Twitter account of the guy who tracks his private plane and also all that guy's other Twitter accounts. It's hard. And I'm not saying that he should or shouldn't do that. I'm saying, it's hard and you have to think about it, because there's no magic formula. You have to list all of the different considerations and see how you personally value them and then guess what? You have to talk to other people to see how they value different things, because they might not value them in the same way. And if you're doing something that involves a community, getting input and getting the opinions of the community is gonna turn out to be really, really useful. So I think it's just a classic example of coming in thinking that this field you know nothing about is gonna be pretty easy to fix, you know?

0:15:21.6 SC: Any possible complications that people might have had in mind was just because they were prisoners of some outdated political point of view. And then, finding out in the harsh light of day, that it's actually quite nuanced and tricky whether you like it or not. I will say parenthetically, again, not having thought of it very deeply myself, but it seems to me, like, some people are pointing at the idea that if you do want to do it correctly, the real problem is not where to draw the line between what's allowed on Twitter and what's not allowed on Twitter, but the procedural question about who gets to moderate? I mean, really the problem is, not... Well, one of the problems anyway is not just what got moderated and what didn't, but that the process for moderating things was entirely opaque, and it was in the hands of a very small number of people. And there's a scaling problem, because any social media platform generally has a huge number of users compared to the number of people working at the company, right?

0:16:17.0 SC: So that's why when you get a tweet deleted or a Facebook message deleted or whatever, it can be really, really hard to figure out why and it's very, very opaque. They don't tell you what the standards are. They don't tell you why you personally have been blocked or banned or whatever, and that's very, very frustrating. So, Noah Smith on Twitter has been emphasizing the superiority in social media contacts of community moderation, and I think that's a very likely to be true idea. You know, I'd like to see more data and empirical analysis about it, but you should have the ability for communities to self-organise and decide what they think is a good moderation strategy. I know that Mastodon is doing something like that. Mastodon is one of the Twitter alternatives. It has its own problems, but... I mean, certainly the interface is super clunky and very hard to use. One of Twitter's advantages and attractions was always how easy it was and not everyone catches on to the importance of that, but you know maybe something like that will happen.

0:17:22.4 SC: Jack Dorsey who is the founder and CEO, former CEO of Twitter, also has made very clear that he thinks now that their problem was they were too opaque and they were trying to do it top-down rather than having community moderation. He has some sort of secret Twitter alternative project, Jack Dorsey, that he's working on, that is supposed to remove social media from being owned by anybody. I forget what it's called, but something like that might be the future. You know, it's just... And there's a whole another interesting thing to think about from the perspective of complex systems research, right? Because there is a thought that you can just think really hard and anticipate what all the problems are gonna be and then write rules. This is the bureaucratic trap, right? The bureaucratic trap is, "I can think ahead to every possible circumstance that will happen in the future, write a set of rules that will deal with it." And it always fails.

0:18:20.8 SC: This is why bureaucracies are horrible, because they can't anticipate all the possible situations that a complex system will find itself in. That's why you need some kind of agency, some kind of ability for a smart, careful, considering person to think about the actual situation you're in, maybe it's unanticipated or unprecedented, and deal with that in some way, or have a community do it, not necessarily an individual. It's that top-down thinking you can predict everything belief that just gets you in trouble with all sorts of complex systems, whether it's a car or a university or a social media platform. So, I think there's a clearly a flaw here in the idea that you just assume everything will be easy and then what happens is you announce that you're gonna do something, it fails, you have to move back.

0:19:10.9 SC: You know, again, just as I'm beginning to record this, there was a story on Gizmodo about Twitter and how you know Elon Musk has scared away various advertisers so he's looking for other ways to make money. And he says that... Gizmodo says, there's a strategy being debated I guess, at Twitter HQ, that says that there's a new strategy that may mandate that you share your location information and let Twitter sell your data to third parties and the company may compel your consent for targeted advertising using your contacts and a phone number that you provided for two-factor authentication. This is almost certainly illegal, [chuckle] the article continues on Gizmodo. But you know, this is an example of, "Well, we're gonna try something. We don't know if it's gonna work, but you know, let's just see what happens 'cause we're kind of desperate."

0:19:58.3 SC: Now, again, as I said at the beginning, I don't wanna be too one-sided here, because it's a balancing issue. Once again, it's not just a balancing issue between different competing interests and therefore the issue is difficult, but there are good reasons to move fast and break things sometimes. You know, we can be in situations again, with complex systems, where you're in what is called a rugged fitness landscape. In complex systems research and also in evolutionary biology, a fitness landscape is, you have some space of all possible choices, space of all possible configurations or genomes or systems or networks or whatever it is, and all of these specific configurations that you can imagine have a fitness, how well they do in their environment, or how well they do with the task they're trying to work at. And because the space of parameters is so large, whether it's your genome or whether it's just all the different possible moderation policies that we could have on Twitter, these are complex systems, and maybe you're in a situation where given what your current choices are there's no short simple easy change you could make that it would improve your life.

0:21:09.7 SC: You are at a peak, a local maximum in the fitness landscape. Everywhere you change by a little bit things would get worse. But somewhere over there, past the valley, there's an even higher peak in the fitness landscape, right? There is a way to evolve if you're in evolutionary biology to an even better way of doing things, but you can't get there incrementally. You have to go through a worse off situation before you can get that advantage. So this is always a tricky thing in evolutionary biology, how do you get there? Sometimes, it takes sort of a disaster, right? The Cambrian explosion, you get a whole bunch of extinctions opening up new niches and then you can explore in a more open-ended way. That's how you find this new even higher fitness peak. So, that's a reason to move fast and break things. There are ruts that we have to get out of and there's a set of context in which that works very well.

0:22:04.9 SC: And not... Less analogically and in the real world, it works very well in startups, right? If you're starting something brand new, there's clearly a value in doing something totally different, right? Doing something really, really new is more likely to be the next big thing. But then when we're evaluating who has done well, there's a huge selection effect, there's a thousand people trying something new and crazy. Most new and crazy things fail and we look at the one that succeeds and go aha, genius, they tried something new and crazy, right? It's exactly like mutations. Mutations in evolutionary biology for an established organism are usually bad. There can be beneficial mutations, but they're exceedingly rare, so we don't just say, "Oh, let's just mutate our genome from generation to generation because we might get better at it." There's a difference between being early in the evolutionary history of life, which is like being a startup versus being later in the evolutionary history of life where we figured some things out, when you're running something established.

0:23:10.4 SC: Elon Musk did not come in and found Twitter, it was already up and running and pretty big, right? So, there's all this complexity, all this interconnectedness. It's like, any computer programmer knows when you're trying to improve some legacy code, when you have some code that has been going on for decades and you've been building on it and modifying it, you don't know what's gonna happen when you delete some module or some subroutine or something like that. You can't see that it has any use, but somehow it's really, really important in a way that you don't know. That's again, the nature of complex systems. And indeed in evolutionary biology, the rate of mutations was way higher early in the history of life than it is now. You know, I think in some sense and I know that not everyone agrees, but I think that Elon Musk is in some sense very sincere about his care for humanity and the Earth. You know, he could have done many things to make money, but between SpaceX and Tesla, as an electric car company, I think that he really did a huge amount to change the world in ways that most people don't.

0:24:13.7 SC: Now, that's not to say that he's at all good at helping actual people along the way. His track record at dealing with employees and things like that is very, very bad, okay? But I don't think that he's sort of an evil genius. I think that he in his mind is perfectly sincere about saving humanity. He's just not been very good at it in his late phase, what is going on now, let's put it, in his career, okay? Which is a little bit different than the other example, which is SBF, Sam Bankman-Fried and the FTX crypto exchange, where unlike in Twitter, where I'm an active user, I know nothing about the world of crypto, etcetera. But how can you help but be drawn in to this story. This guy, this young guy Sam Bankman-Fried had a net wealth that went from $26 billion estimated to zero in a remarkably short period of time, because of the collapse of his crypto exchange FTX. And it was not just bad management. It seems very, very clear that there was outright fraud going on in a lot of ways.

0:25:19.7 SC: And just like Elon Musk, he turns out to be, you know, inveterate oversharer on the Internet. SBF, as he is known, has done a lot of interviews since his collapse, where he basically says, "Oh, yeah, a lot of the stuff I did was just kind of fooling people to get them to give me money." [chuckle] And then, you know, he claims he's not responsible for the actual fraud, but it kinda seems like he is. It's pretty clear that he is. And the question is... And so, you know, a lot of people invested, a lot of people put their money in his crypto exchange and lost it, a huge number of people. And not just people off the street, there was a community. One of SBF's strategies was, he was extremely active in effective altruism. Which our former podcast guest, Will MacAskill, was a founder of, is a founder of, and is still very active in, and Will was very close to SBF. In fact, introduced SBF and Elon Musk to each other.

0:26:16.3 SC: I don't think they did anything together, but that he tried. And so, you can ask, how can someone who I think is extremely smart and is absolutely a 100% sincere, like Will MacAskill, how can he get taken in by someone who is more or less clearly not, like SBF? And you know, there's probably lots of psychological explanations there, but I think that part of it is a way that we think about smartness, right? You know, there's a couple of little factoids that I will share that shaped my thinking here. One is, there's this video that you can see of, there's a infamous pitch to investors that SBF was doing. He was doing a Zoom call where he was trying to get people to invest. And when you're doing a Zoom call, your eyes are glancing around, you know, you're not necessarily making eye contact, maybe your camera is not where your screen is, etcetera, okay? So it's a little bit different kind of interaction. But it turns out he was playing video games the whole time. [chuckle]

0:27:18.7 SC: And you know, he was talking, right? And he was making sense and he was making his pitch, but he was not completely concentrating on the task at hand. He was playing a video game in the background. And the interesting thing is not that, the interesting thing is that the investors when they found out, thought it was awesome. They're like, "Wow, how smart is this guy that he can make such a smooth slick talking pitch like that while his attention is distracted by a video game." And that just amazes me, this is why I will never be an investor. I'd be like, Why in the world would that be considered good? Why in the world would you find out that someone was completely... Their attention was completely elsewhere while they were asking you to give them a whole bunch of money and go, "Wow, that person's really smart." I'm not gonna say what my response would be, but it would not be that. Let's just put it that way.

0:28:12.3 SC: It's a valorization of a kind of glib quickness and fast talking over careful thought. I see this in guest suggestions for the podcast all the time. I get lots of great guest suggestions for Mindscape and I often take them. Many of my guests have been people I didn't know about before, but people suggested them, so I look them up. But I get way more suggestions than I can possibly ever take, and some of them are, "You know, you should talk to this person because they're really, really smart." And I say like, "Well, okay, what are they smart about? [chuckle] What have they done? You know, what is the topic that they know more about than anyone else?" And the answer is like, "Everything! They're just good at everything. They have a take on absolutely everything in the world." That is a complete turn off to me. That gives me a very bad feeling. I'm instantly repelled by that idea, you know?

0:29:03.8 SC: There's value and it's good to be quick and to have opinions about things. Breadth is good, but so is depth; you need a little bit of both. Again, if you're going to be a pundit, if you're gonna be just a commentator, then that kind of breadth and ability to bounce back-and-forth from topic to topic is very valuable, an essayist, let's put it in the most positive light that we can, right? And there's absolutely a place for that, a critic, an essayist, there's absolutely a place. But mostly, not exclusively, but mostly, I'm looking for the depth when I'm here on the podcast. I'm looking for people who have really thought through the nuances of something. As a person, I would want both. As a podcast guest, I'm looking more for the depth. The other clue... And again, I'm gonna keep saying this over and over again, I have not read very carefully about this, I'm just giving my off-the-cuff opinions.

0:30:01.0 SC: But there is a quote by SBF where he told a journalist that he thinks every book is a mistake. He would never read a book. No one should ever write books. Every book should just be a blog post, it's a waste of time. And again, I'm thinking, "Wow, like, how in the world could so many smart people think that that was the sign of a true genius person who's gonna make a lot of money and make the world a better place?" There's warning signs here, you're ignoring the red flags. [chuckle] To me, like, I think that even if you want some new hot shot brand new idea, get it from someone who shows some interest in being a little more careful and deep than that. And with that, let's switch gears a little bit. Let me talk about foundations of physics, which sounds like a completely different topic and it is a completely different topic, but there's a through line here once again.

0:31:02.5 SC: And by the way, I should tell you what I mean by foundations of physics, 'cause it's a slightly different thing. Philosophy of physics is of course, a well-established field as is foundations of physics, but the more common phrase you will hear is philosophy of physics or philosophy of science, and foundations is sort of some... Maybe a subset of philosophy of physics, but also, you can do foundations of physics without being a philosopher at all. Just sort of a certain kind of careful deep way of doing physics. Philosophy of physics might include a lot of theory choice and methodology and epistemology or even history of physics, whereas foundations of physics is really the same goal as physics. Philosophy of physics is sometimes trying to describe and understand the process by which physics gets done. Foundations of physics is trying to understand the universe, is trying to understand nature, is trying to understand reality just like physics is. But it's doing it in a way, it's a style within our attempts to understand nature better.

0:32:06.7 SC: And I was thinking about this, because I gave an introductory talk here at Johns Hopkins at the physics department, a little talk on, you know, foundations of physics bootcamp. What is foundations of physics and in what ways might it be helpful to actual working physicists? So, I had a chance to think about what the answer to that question is. And there's lots of answers and it's actually a case where it's probably better to just go through the examples and decide for yourself what their commonality is. But one theme I kept returning to was patience. In other words, the idea of being willing to say, "Well, why is that true? Okay, why is that true? Why exactly is this thing true?" Physicists, as much as I love them and am one of them, they are very happy to get the right answer for the wrong reasons. They are very, very focused on getting the right answer, saying the thing is... What the thing is that nature does that will be predicted by their models, that will be seen by their experiments.

0:33:11.0 SC: That's not a bad thing. You know, getting the right answer is a very, very good thing. But sometimes, you get the right answer and you don't have real clarity on why you've gotten it, but you have a set of things you can say that are kind of good enough, right? Quantum mechanics is the obvious example here, where almost a hundred years after the Solvay Conference, we still don't have a consensus on what's going on in quantum mechanics, but we have no trouble using it, right? We can make the predictions for the LHC or for superconductors or whatever, without knowing the ontology of quantum mechanics. And as you know, if you listen to me talking about these things, the vast, vast majority of physicists are perfectly happy with that. You know, it's one thing to say that we have a challenge, there's something we don't understand, there's always things we don't understand. The weird thing about the foundations of quantum mechanics is, how happy we are with not understanding, you know?

0:34:06.9 SC: We're professional physicists [chuckle] and yet, we're perfectly content to leave some of these really, really deep questions about physics by the wayside. And I think that's kind of wrong. And it's not only quantum mechanics. In quantum field theory, there are deep foundational questions. There's something called Haag's theorem, H-A-A-G, Rudolf Haag, which was developed by other people also, but... And I'm not gonna go into it, because it's very, very nuanced and even the philosophers and foundation people, foundations of physics people argue about what it says and what it means, but basically the seeming implication of Haag's theorem is that there's a way that in quantum field theory we go about actually doing calculations, which is, we often turn off the interactions of our electrons and photons, for example, so we can just understand what the world would be like if there were no interactions, so just electrons or photons flying freely not interacting with each other. And then we turn on the interactions, let them interact, and then turn them back off again, and we sorta try to match the behavior of the interacting theory to the non-interacting theory to make a prediction.

0:35:20.3 SC: And roughly speaking, Haag's theorem says that you can't do this, [chuckle] that you can't do this in a way that preserves a lot of the structure you wanna preserve, like the behavior of different fields and their commutation relations and so forth. So, this naively says, you know, again, naively, that everything we do to make predictions with Large Hadron Collider is complete nonsense. But guess what? It works really, really well. So, I know that it works and it does work for a reason, but we're not very sure what that reason is. And to me, I would like to be more sure what that reason is. And maybe the reason is simple, but it's not something I don't think we currently understand. And there's other examples as well, the arrow of time, the fact that you need a past hypothesis of early low entropy, is something that is just not understood by most physicists who are teaching statistical mechanics. The foundations of statistical mechanics is a very important and open area.

0:36:19.4 SC: In my own field, whether it's cosmology or particle physics, we talk a lot about fine-tuning and naturalness, you know, whether certain parameters are natural, whether fine-tuned, whether we should be surprised, whether you need a multiverse, whether there's some dynamical mechanisms. Guess what? We have not as a physics community thought very carefully about what that means. Some people have tried. They've not done a great job, honestly. But so, again, we're using these ideas without knowing exactly what they're on about, because we wanna hurry up and get the answer. We don't have the patience to think really slowly about what we're doing. And there's a very strong motivation for that, getting the right result, getting the right model, predicting the outcome of the experiment, that's ultimately what we want to do. And again, there's an analogy with the startups, right? If you try a million different startups and most of them fail, there is a very strong weeding mechanism, right? You're gonna try to make money, you're trying to make a product that becomes popular in the marketplace. So, there is a criterion for success and failure.

0:37:24.9 SC: Likewise in physics, if you have some ideas, there's a very strong criterion for success and failure, are you predicting the right experimental outcomes? When you're in a situation where you have huge guidance from experimental or empirical data, wrong ideas get shot down quickly. And so, go ahead, you can get a lot of right ideas just because nature guides you to them kicking and screaming. But sometimes, there are important questions for which the experimental guidance is kind of meager, right? When we're talking about why is the cosmological constant a small number, why is the mass of the Higgs boson so much lower than the Planck scale, these are potentially fraught questions with sort of physical implications, because maybe the answer is something to do with supersymmetry or some new physics or something like that, but there's no immediate experimental guidance to how to think about it.

0:38:21.7 SC: So, what happens is, the old ways of thinking that were perfectly good when the experiment would just tell you when you were wrong, aren't as much help in the these deeper, more foundational questions. And so, you need to think a little bit more carefully. You need to ask why you thought that a certain number was natural in the first place and so on. And I think there's a lot of ways that this foundational thinking can help with good old physics. You know, I think this is clearly true in quantum mechanics. I'm increasingly thinking it's true in cosmology, that's one of the big things I want to write papers about in the next couple years. I think there's sort of a lot of ways we could improve our understanding of naturalists and fine-tuning in cosmology by thinking foundationally, by thinking more carefully, more slowly even than we do.

0:39:10.2 SC: So, to close, I'll try to give you an example. An extended story that maybe speaks to the helpfulness, the usefulness of thinking carefully and slowly about theoretical physics, even if you don't really care about the philosophical side of things, you just care about the physics side of things. So, in the early 1950s, David Bohm was a young assistant professor at Princeton and he ultimately got in trouble. He had communist sympathies, he had hung out with some communists back in the day that prevented him from working at Los Alamos during Manhattan Project, and in the early '50s it was the height of the Red Scare, the McCarthy era, the house on American Activities Committee. And he ran into trouble with them and eventually the president of Princeton locked him out of his office and fired him and he couldn't even get jobs anywhere in the United States, he had to move to Brazil. That's not the story that I'm thinking of, I'm thinking of a different story about David Bohm in the early 1950s, which is that he wrote a textbook on quantum mechanics.

0:40:11.7 SC: And it was a very straightforward, you know, conventional wisdom textbook. He was not trying to rock the boat or anything like that. But it was still, you know, I wouldn't say the early days of quantum mechanics, but things were still settling and they were still in the afterglow of the early days where all of the possibilities were being debated and we hadn't quite settled in on the final answers. So Bohm talks about the possibility of hidden variables in his book. So in other words, the idea that not only is there a quantum mechanical wave function, but there are other physical quantities that go into determining your quantum theory. And he didn't talk about it in any great depth, he merely quoted a theorem by John von Neumann, that proved apparently, supposedly, that hidden variables were impossible, that you could never reproduce the success of quantum mechanics with hidden variables.

0:41:03.3 SC: The problem is that von Neumann's proof, and von Neumann was a genius mathematical physicist, but his proof was written in his book, The Foundations of Quantum Mechanics, and... Or was it that? Or was it the mathematical principles of quantum mechanics? I'm not gonna remember the title of von Neumann's book, but the book had not yet been translated into English. It was only in German and like many other Americans, Bohm was not a German speaker. But at Princeton, there was someone who cared very, very deeply about the foundations of quantum mechanics and did speak German, namely Albert Einstein. So, Einstein saw Bohm's book and leafed through it and summoned him to his office, right? So when you get a summon to go to Albert Einstein's office, you go, and Einstein says, "Look, you say that this thing is proven here, but... " He opens von Neumann's book in German, he says like, "He's making all these assumptions that might not be true. This doesn't prove anything all about the real world."

0:42:01.1 SC: And Einstein was right as Einstein very often was, and it made a big impression on Bohm. So, Bohm went back and started thinking about it and said, "Well, okay, if that proof doesn't quite prove the sweeping conclusion that it is apparently trying to lead to, can you make a theory of hidden variables?" And so, he did. He made a theory called Bohmian Mechanics and it's actually very close to a previous theory by Louis de Broglie, so sometimes we call it de Broglie-Bohm theory. And he wrote about it and you know, the secret is to be non-local. The hidden variables in Bohm's theory have explicitly non-local interactions. What one particle at one point in the universe is doing is affected by other particles elsewhere. And no one cared. [chuckle] No one was really interested. I mean, Bohm's thesis advisor was, J Robert Oppenheimer who says, "Okay, now we can just ignore him, because he's gone a little crazy, modifying quantum mechanics."

0:42:58.9 SC: There was one person who was not unimpressed, who was very, very stricken by Bohm's result who was called John Bell. John Bell at the time was a physicist at CERN working again on very normal quantum field theory particle physics kinda problems, but he had this interest in the foundations of quantum mechanics and he read Bohm's papers and was really struck by how like, apparently Bohm was doing something that was supposed to be important. And he noticed that there was non-locality in there. And so, Bell says, "I wonder if this non-locality that is part of Bohm's theory is necessary? Could we get rid of it," right? And he ends up proving Bell's theorems, and deriving the Bell inequalities, which basically says that you need some kind of non-locality in quantum mechanics, again, under certain technical assumptions you can get rid of, but it's a very sweeping kind of thing. And he really gives a way of delineating which kinds of correlations you will get in a quantum mechanical-like theory and you know, some kind of local, more classical kind of theory.

0:44:06.7 SC: And again, he was hiding from his friends. Bell did not want his colleagues at CERN to know about it. He was working on weekends. He finished the paper during a sabbatical, the whole thing. And it didn't make... When he published his papers, didn't make a big splash, but so... As we now know, it did eventually make a big splash. The Bell inequalities became of great interest to people working on quantum information and entanglement, and the most recent Nobel Prize was given to Clauser, Aspect and Zeilinger for their experimental tests of the Bell inequalities. And the punchline to this whole story is, the Nobel Committee when giving out the press release, announcing the Nobel Prize, completely got it wrong. They wrote in their press release that John Bell had proven that hidden variable theories were impossible, which is exactly the opposite of the truth. What he proved was that non-local was the only way to be a hidden variable theory. Local hidden variable theories are impossible. Again, [0:45:09.4] ____ possible, more assumptions you have to make.

0:45:15.0 SC: But Bell was a huge booster of hidden variable theories. Bell was always telling people that we should teach Bohmian Mechanics in quantum mechanical textbooks. He didn't quite absolutely have a belief in it, but certainly his favourite theory of quantum mechanics was Bohmian mechanics. So, to present Bell's theorem as a proof that hidden variable theories can't work is exactly backwards. So, you know, if even the Nobel Committee can make mistakes like this, I think that maybe there is some value to thinking more carefully about these issues. I think that, you know, physicists absolutely do think carefully about their narrow technical problems. That's one of the ways that physicists have been amazingly effective and making such enormous strides in understanding the universe by just digging super deeply into a particular kind of thing. And the really good ones, no more than one kind of thing and they can bring them together and make connections and that's great.

0:46:17.8 SC: But you don't just say, "Okay, it's working, let's just move on with it," right? I don't know how to actually make people think more deeply about things. You know, you joke about things. I think maybe like, have a new rule where you're only allowed to publish papers in even number years and in odd number of years you have to read a book [chuckle] or read many books or read other people's papers. I don't know what the ways to change the incentive structures are, but I do think that whether it's being a working physicist or a tech mogul trying to change the world, we should place a little bit more value than we do on going deeply, being patient, thinking carefully, thinking very, very slowly about the very difficult questions that we're trying to address. And with that very paternalistic kind of message, not especially inspired message, but I hope one that you are prepared already to take to heart, happy holidays everybody. As you know, I take next week off, things to do and I'll see you on the flip side early January with a whole new year of the Mindscape Podcast. Thanks for your support this year. Take care.

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