Martín de Azpilcueta

Martín de Azpilcueta (1492–1586), called Doctor Navarrus, was a Navarrese canonist, theologian and economist, born at Barásoain into a noble family. After studies at Alcalá and Toulouse, he held canon-law chairs at Salamanca from 1524 and taught at Coimbra from 1538 to 1555.

With Francisco de Vitoria and Domingo de Soto he was a leading light of the School of Salamanca, and in 1556 he first formulated the quantity theory of money. Philip II entrusted him with the defence of Archbishop Bartolomé Carranza before the Inquisition, and he ended his years in Rome as counsellor of the Apostolic Penitentiary under Pope Pius V.