Last time as you'll recall, we, we I introduced the dealer model here, trainer dealer's model. And we were thinking about it as a model of a dealer who is, is a security dealer is, is trading bonds, stocks and bonds stock. But bonds. and moving the price that he quotes, the bid ask spread here Depending on his position, his inventory as we said, okay? and we talked about what that, what that dealer does, and, and how he sort of converts funding liquidity, which he uses to finance his inventories into market liquidity. Our ability to buy or sell quickly without moving the price and volume really depends on agents like this, profit seeking agents, who are willing to take the opposite side of that trade for a price, okay? And the price is the diviation of the price they are quoting from any fundamental value. That is what it costs us in order to have equity, okay? That's, that's the point of yesterday's lecture. Now, the next step in the class, okay? These are security dealers, right? And so they're sort of, in, in my concept of the hierarchy of money and credit, okay? They're pretty far down, okay? it doesn't mean their social status or anything. Just that they're, they're pretty far removed from the best money in the world, international reserves or something like that, okay? So we want to ascend the hierarchy now and start talking about banks. And so let me just first to motivate today, okay? Give you a puzzle. When we're talking about banks typically I mean in, in, in when I talked about the, the hierarchy of money and credit. I said we're going to talk about banks as making markets between two layers of the hierarchy if you remember. Between currencies and deposits, okay? And the price that's relevant between these two things is par, okay? A price of one. Currency and deposits trade one for one. This might remind you a little of a money market mutual fund issue that I just raised. So this is a little different than the security markets, right? You know, if, if, you're making markets, you can't move the price. You know, if you're making this kind of market, you, you, can't move the price. And we emphasized how it was very important for the dealer to be able to move the price in order to shelter themselves from risk. That the, that somebody on the other side might know more than them or if there's price fluctuation or something like that. So it's, it's there's two puzzles here. One is how can they possibly make a market without moving the price. With, with, without being able to change the price. How's it even possible? And how's it even profitable? You know, why would anyone do this, okay? Since again we're emphasizing the profit seeking dealers our whole model. So if you think about the difference between the, this bank American banking thing and what we have up here. You say to yourself, well first of all we have a fixed price of one here, okay? They can't really change depending on the inventory, that's the whole point, okay? Not only that, there's no bid-ask spread, right? You have to be able to move from the currency into depositing, depositing the currency at the same price. There's, so, so, there's a big difference, it seems, between banks and this model because there's no bid as spread. And the price by, by, by design, okay, is, is fixed. Okay. So this is the puzzle. How can we use this model? ' Kay. When you, one of the life lessons I have doing economics for long time is when you confront a puzzle like this it's better not to hit it head-on. Because it just means there is, there is too many, there's too many intervening steps. Okay. So let's just back up. Okay. And we'll come to this. Okay. Let's back up. Let's back up and let's think about our security dealers first, okay? [BLANK_AUDIO]