John of St. Thomas

John of St. Thomas (1589–1644), born João Poinsot at Lisbon, studied at Coimbra and Louvain and entered the Dominican order at Madrid in 1610, taking the religious name by which he is known. He taught at the Dominican college of Alcalá and from 1630 held the principal chair of theology at the University of Alcalá. In 1643 he became confessor to Philip IV of Spain and died the following year.

He is one of the great Thomist commentators. His Cursus philosophicus thomisticus covers logic and natural philosophy, and his treatment of signs in the logic has attracted modern philosophers. His Cursus theologicus is a commentary on the Summa theologiae in the tradition of Cajetan and Báñez, and its treatises on the gifts of the Holy Spirit and on the knowledge of God were especially influential. Later Thomists, including Jacques Maritain, relied on him heavily.

The library holds the two parts of the Ars logica and the first part of the natural philosophy from the Cursus philosophicus thomisticus. The first part of the logic, on formal logic, is the natural place to begin.