Suárez was perhaps the greatest of the early modern Scholastics. This Spanish intellectual entered the Society of Jesus in 1564 and thereafter studied theology at the University of Salamanca. He taught philosophy and theology at various Jesuit colleges, including the Collegio Romano and the Colegio das Artes at Coimbra. In addition to several commentaries on the texts of Aristotle and Thomas Aquinas, Suárez wrote perhaps the best late Scholastic treatment of metaphysics, his Disputationes metaphysicae (1597). In this text, he treated the views of Thomas with great respect, reflecting the fact that the Jesuits were enjoined to follow the teachings of this Catholic saint. Nonetheless, in his text Suárez also sided on points of detail with the anti-Thomistic views of John Duns Scotus, and he was not afraid at times to stake out his own distinctive position on the metaphysical issues under consideration.

Despite the importance of Suárez for Scholastic thought, there is no evidence that Descartes knew of him or his work before 1640. During this time Descartes’ knowledge of Scholasticism derived mainly from the Scholastic textbooks he had studied as a student at La Flèche, which did not include Suárez's metaphysical treatise. Descartes’ first reference to Suárez is in his response to Antoine Arnauld's objections to the Meditations. In particular, Descartes attempted to defend the cogency of his view that claims that certain ideas can be “materially false” by appealing to Suárez's own use of the notion of material falsity in his Disputationes. But though Suárez does anticipate there Descartes’ view that there can be a kind of falsity that does not involve judgment, he does not conclude, as Descartes does in the Third Meditation, that certain sensory ideas are so obscure that we cannot determine whether they are materially false in the sense that they “represent what is not a thing as if it is a thing” (AT VII 44, CSM II 30) (see Wells 1984).

There is in fact a more substantive connection to Suárez in Descartes’ theory of distinctions (see distinction [real, modal, and rational]). Descartes was initially prompted to consider the Scholastic theory of distinctions in responding to Caterus's objections to the Meditations.