Juan Caramuel Lobkowitz was one of the most important and prolific intellectuals of the seventeenth century. He wrote on theology, philosophy, mathematics, astronomy, logic, linguistics and architecture. Born in Madrid, this Cistercian monk studied in the order’s Castilian monasteries and at the universities of Alcalá and Leuven; he travelled throughout Europe holding various ecclesiastical positions and ending his days as bishop of Vigevano (Italy). He took part in the debates that led to the Peace of Westphalia (1648) and, as an expert in ballistics, made a decisive contribution to defending Leuven and Prague from the Protestant siege. He corresponded and debated with some of the foremost intellectuals of his time (Descartes, Nieremberg, Pascal, Gassendi and Kircher, among others). His vast and original oeuvre includes Theologia moralis, a landmark work that was an essential subject of discussion in its time from the first edition (1645) onwards; Theologia rationalis, which includes a pioneering treatise on grammar; and Mathesis biceps (1670), in which he presented the first credentials of the binary system and probability calculus. Much remained unpublished.