What are money? People, it seems, never think about it. They’re used to the fact that money exists. But what do we have? How is the whole system устроєно?… It turns out that our modern money has been widespread everywhere since the 17th century: it contains an interest component. And interest fuels competition for money—and it feels good only when money is scarce in general. That’s what money everyone is used to, and they can’t even imagine that parameters could be different! Yet before the 17th century, interest-free money was dominant, and earlier there was even a currency system with negative interest! With other parameters, people behave differently… This is what the book by the major scientist and financier B. Lietar is about.