I wanna ask a little bit about your time at Jane Street. You worked in the London office. And 1 of the things that I think fascinates a lot of people is they see these stories of the news of these top quant shops raking in billions and billions of billions of dollars, but it seems like a black box. You know, we have the efficient hypothesis of the market. And, obviously, if these guys are capitalizing on all these different inefficiencies, that can't 100% be true. How do these quant shops hire talent that can continuously generate and execute on their edges and make money. I think every great trading firm has an origin story that looks something like, this is something we figured out how to do that was fairly simple, pretty self contained that we could start with, and build from there. If you start trying to build a massive firm from day 1 that does everything, you'll probably fail. Trading is 1 of those things that yields to incremental improvements. I think 1 of Jane Street's biggest edges is that whatever it is that's the worst thing that they do, they're pretty decent at. Right? And so they're very good at some things, but even their worst thing, and I don't necessarily know what that is, they're still pretty decent at it. That's the nature of trading. And then colonizing adjacent markets is probably the other natural way to go about it. You start with a small thing that you know you can do well, and then what's the next thing? What's the thing that's most similar to it that we're not doing and start doing that thing? How do you know you have edge? How can you be sure? So I think if we're being honest with ourselves, I think the answer is you can't. You can't know for sure. All you can really say is statistical things. Right? Like, I did 1000 trades, and I made money on 55% of them. And the amount of money that I made on the 55% was about the amount of money that I lost on the 45%. Like, I have some good statistical bounds on what is the probability that I just got lucky. Right? So, certainly, that's what pushes quant trading firms in the direction of doing more trades, more high frequency stuff, in part because it gives you more data, but also because it gives you more statistical certainty that you have something. If you're doing something more discretionary, it's a lot harder to say, yeah. Like, I definitely definitely have edge or I definitely can do this thing. An analogy that I would give, if you don't mind, is with poker, where if you just look at the statistics of win rates and that sort of thing and you're trying to figure out is this person a winner in this game, it takes a 100,000 hands or more to really figure out, like, is this person actually making money, or are they just on a big massive heater? But if you look at their hand histories, if you look at the individual decisions they made, like, a really good poker professional can, in a span of 1,000, maybe at most 1000 hands, can tell, yeah, this person is good. This person's beating this game or not. And so you can think about the that 2nd kind of studying a poker player as more applicable to discretionary trading. Like, what is the thought process? What is the way in which they're developing edge, thinking about it, improving it? How do they self regulate? How do they control the, you know, things that happen? Is that a statistical statistically significant sample size? Perhaps not. But we have all this other information we might be able to integrate to get get to a better sense. Do we know for sure? I don't think so. On that note, 1 of the things you mentioned in your book, the laws of trading, is that there are extreme events that can occur. And another thing you mentioned is there are quant shops that aren't truly fully systematic. And what I mean by that is it still requires someone to turn the thing on and and off and make a decision on whether or not the market conditions are ones in which the model will behave as it has in the past and thus make money. During crises, moments of crises such as, let's say, dot com crash or 2008 or even 2020 or 2022, these periods of insane volatility. Let's say you're trading market movements, but you're using data that maybe is not applicable to the current regime. How does a skilled trader navigate that? I think it depends a lot on the kinds of strategies that you're running. If you're running something that's very automated, very systematic, you basically just have to make a judgment call about whether the situation that you're in is in sample of your training data, whatever you use to train your model. If it is, great. Keep going. If it isn't, then you have another judgment call to make about whether, given that it's out of distribution, is this still is this going to be a good or a bad time to turn the machine or the system on? So if you're a systematic trader, there's still a couple of maybe decision points. It is worth noting that in times of crisis, like when things are very volatile, etcetera, etcetera, those are generally very good times to trade if you are not forced to trade because the nature of the volatility is that people are forced to trade. Maybe there's some liquidation somewhere that's forcing somebody to sell out of a position. Maybe there's a margin call, something. Right? That's part of what's driving that volatility. Big moves drive big trades. If you're not constrained in that way, I if you have enough risk capital to deploy during those times, those are very often extremely good times to trade. And so maybe your system doesn't actually have to keep nearly as much of the relative edge because there's enough absolute edge to maybe make up for that. And so that's another thing to keep in mind. I think in particular of market making strategies. Right? Like, when things are very volatile, then the value of somebody always being able to buy and sell at a price goes up. Like, that is a more valuable service when things are volatile. And so you should be, if you're doing things right, making more money when things are volatile. And And then maybe on the more discretionary side, it's about all those other soft things. Right? Like, am I making good decisions? Am I understanding the world properly? Consulting with people you trust? Like, all these sorts of things factor in. Now I wanna go back to what I kinda talked about towards the beginning of this conversation. Talking about all these quant shops, quant trading firms, quant funds, just raking in huge sums of money. And it feels to me as an outsider looking in that these firms have all the money. They can hire all the talent in the world. They have access to the best technology. Where do you see the future of quant trading stops, quant funds, maybe even multi managers? Do you think that they will continue to get bigger and that smaller players are gonna essentially be wiped out? There's a couple things there. 1 is I think there's an interesting question of why is it that the profitability of these companies it's definitely gone up in the last 10, 15 years. What is the source of that? The waterline has risen. Like, it's much harder as a small shop with probably a big technological research cost disadvantage to compete with with these companies that are progressively getting more automated. Like, the standard answer was, like, go figure out how to trade the bottom end of the Russell because big quant shop is kinda just not worth their time to focus on that. Right? I think that's still somewhat true probably, but less so than before because the marginal cost of adding some more marginal product just keeps going down and down as automation just keeps making things easier for large firms. And, also, those things just trade more anyway, there's just probably more money there to begin with. I do think it gets harder and harder for individuals, for small shops to to compete. I definitely believe that. I think there's definitely a consolidation that's happening. Probably the most obvious places in options where used to be there is probably, like, a couple of dozen options market making firms that could make a decent living at it, but the technological lift, the sort of the fixed cost of being able to be an options market maker just keeps going up and up and up, and that kind of prices out a lot of medium and small sized shops. And you've seen this consolidation in the last, like, 5, 10 years. Begging the question of why is it the profits of these firms has gone up and up and up in the last 10 years? We'd love to hear from you. Yeah. Look. I certainly don't know. It's something that I and my friends wonder about. I think 1 plausible source is, like, the world has gotten richer, and so, like, there's just more money out there. The other thing is to the extent that old line investment banks like Goldman or Morgan Stanley or or JPM, they used to internalize a lot of their client flow, and that money used to be made by these investment banks. I think that's changing. Right? Like, you see a lot of these quant firms, for example, entering into bond markets. It used to be very much controlled by investment banks. The investment banks are being disintermediated. Like, the the end customer, say it's like some pension fund in Brazil, is going straight to the the ETF market maker to say, hey. What's the price you can make me on a $100,000,000 of EM? Like, that like, the middleman is getting cut out. And so maybe a lot of those profits are just kinda getting shifted in the direction of the firms that are actually taking the risk as opposed to just being the middleman. So so that might be 1 possibility in addition to the world getting richer. I do also think, sadly, that in some countries, certainly like India and The United States, we've seen a huge growth in retail trading in post COVID. There's a lot of quant firms making money off of a lot of small retail people gambling that they should. Right? Definitely see a trend in the last 5 years of the world is going in a more pro gambling direction. Like, gambling is legal now. Lots of people trade now. Like, prediction markets are growing. It's what I'm calling, like, the gamblization of everything. And if you're making markets in a growing market, you're probably gonna make more money.