In 1609 a 73-year-old Jesuit was prosecuted for lèse-majesté and locked up in a Madrid convent. His crime: a treatise on coins.
Juan de Mariana’s De monetae mutatione went after Philip III’s favourite trick, minting vellón coins with ever less silver in them. Mariana’s argument: debasing the currency is a hidden tax, collected without the people’s consent, and it lands hardest on ordinary people while the Crown keeps spending. He saw that multiplying the coins in circulation makes prices rise, describing monetary inflation centuries before the word existed.
The treatise was put on the Index and expurgated; the old man spent around a year confined. He was right on every count.
Four hundred years later “inflation is the cruelest tax on the poor” sounds like a modern slogan. It cost a Jesuit his freedom in 1609.
https://juandemariana.org/tratado-y-discurso-sobre-la-moneda-de-vellon-coleccion-de-ensayo-politico/