Gabriel Vasquez, the neo-Scholastic theologian, was born at Villascuela del Haro, Spain, and died at Alcalá. Educated in the Jesuit houses of study in Spain, he taught moral philosophy at Ocaña from 1575 to 1577 and theology at Madrid and Alcalá. Eventually he succeeded Francisco Suárez in the chair of theology at Rome, where he taught from 1585 to 1592. His Commentaria ac Disputationes in Primam Pattern S. Thomae (8 vols., Alcalá, 1598–1615), a lengthy commentary on Part I of Thomas Aquinas's Summa Theologiae, contains much philosophical speculation. A posthumously published summary of this work, Disputationes Metaphysicae (Madrid, 1617), helped to popularize his philosophy.

Vasquez's most influential contribution lies in his distinction between the formal concept in the understanding (a mental entity, or "idea," constituting knowledge, qualitas ipsa cognitionis) and the objective concept that is the reality that is known (res cognita) through the formal concept (Commentaria I, 76, nn...