The secret heresy of Hieronymus Bosch

Bosch's work was intended to convey a double meaning. Outwardly his paintings were traditional enough to be accepted by his wealthy patrons and the Church authorities. But behind their appearance of orthodoxy, they portray the doctrines and attitudes of Catharism, the medieval gnostic and dualist heresy which affirmed that the earth was literally Hell, ruled over by Satan.

A movement thought to have been extinguished by the Inquisition, it is now known to have existed in Bosch's time and he, according to the author, was a secret believer.