Money is at the same time the clearest thing and the most difficult to understand. This paradox is set out by Anselm Jappe, the author, among other works, of La société autophage (2017), which shows us where this problem comes from. As a commodity, money has become the supreme commodity, the only commodity, the ultimate fetish, and the cause of a completely irrational order, capable of producing unprecedented catastrophes, like that of 2008.