What is money? People never seem to think about it. We got used to what we have. What do we have? How does the whole system work?.. It turns out that our modern money has become widespread since the 17th century: it contains an interest component. And interest accelerates competition for money and feels good only when there is a general lack of money. This is the kind of money everyone is used to and can’t even imagine that the parameters could be different! But until the 17th century, interest-free money dominated, and before that there was a system of currencies with negative interest! With other parameters, people behave differently... This is a book by a prominent scientist and financier B. Lietar. The translation in this form was published in the electronic almanac Art&Fact No. 1(1), 2006