His most important philosophical achievements were in metaphysics and the philosophy of law. He adhered to a moderate form of
Thomism and developed metaphysics as a systematic enquiry.
Metaphysics For Suárez, metaphysics was the science of real essences (and existence); it was mostly concerned with real
being rather than conceptual being, and with immaterial rather than with material being. He held (along with earlier scholastics) that essence and existence are the same in the case of God (see
ontological argument), but disagreed with Aquinas and others that the essence and existence of finite beings are really distinct. He argued that in fact they are merely
conceptually distinct: rather than being really separable, they can only logically be conceived as separate. On the vexed subject of
universals, he endeavored to steer a middle course between the
realism of
Duns Scotus and the
nominalism of
William of Occam. His position is a little bit closer to nominalism than that of
Thomas Aquinas. Sometimes he is classified as a
moderate nominalist, but his admitting of
objective precision (
praecisio obiectiva) ranks him with moderate realists. The only veritable and real unity in the world of existences is the individual; to assert that the universal exists separately
ex parte rei would be to reduce individuals to mere accidents of one indivisible form. Suárez maintains that, though the humanity of Socrates does not differ from that of Plato, yet they do not constitute
realiter one and the same humanity; there are as many "formal unities" (in this case, humanities) as there are individuals, and these individuals do not constitute a factual, but only an essential or ideal unity ("In such a way, that many individuals, which are said to be of the same nature, are so: only through the operation of the intellect, not through a substance or essence of things which unites them"). The formal unity, however, is not an arbitrary creation of the mind, but exists "in the nature of the thing, prior [ontologically] to any operation of the intellect". His metaphysical work, giving a remarkable effort of systematisation, is a real history of medieval thought, combining the three schools available at that time:
Thomism,
Scotism and
Nominalism. He is also a deep commentator of Arabic or high medieval works. He enjoyed the reputation of being the greatest metaphysician of his time. He thus founded a school of his own,
Suarism or
Suarezianism, the chief characteristic principles of which are: • the
principle of individuation by the proper concrete entity of beings • the rejection of pure potentiality of matter • the singular as the object of direct intellectual cognition • a
distinctio rationis ratiocinatae between the essence and the existence of created beings • the possibility of spiritual substance only numerically distinct from one another • ambition for the hypostatic union as the sin of the fallen angels • the Incarnation of the Word, even if Adam had not sinned • the solemnity of the vow only in ecclesiastical law • the system of Congruism that modifies
Molinism by the introduction of subjective circumstances, as well as of place and of time, propitious to the action of efficacious grace, and with predestination
ante praevisa merita • the possibility of holding one and the same truth by both science and faith • the belief in Divine authority contained in an act of faith • the production of the body and blood of Christ by
transubstantiation as constituting the Eucharistic sacrifice • the final grace of the
Blessed Virgin Mary superior to that of the angels and saints combined. Suárez made an important investigation of being, its properties and division in
Disputationes Metaphysicae (1597), which influenced the further development of theology within Catholicism. In the second part of the book, disputations 28–53, Suárez fixes the distinction between
ens infinitum (God) and
ens finitum (created beings). The first division of being is that between
ens infinitum and
ens finitum. Instead of dividing being into infinite and finite, it can also be divided into
ens a se and
ens ab alio, i.e., being that is from itself and being that is from another. A second distinction corresponding to this one:
ens necessarium and
ens contingens, i.e., necessary being and contingent being. Still another formulation of the distinction is between
ens per essentiam and
ens per participationem, i.e., being that exists by reason of its
essence and being that exists only by participation in a being that exists on its own (
eigentlich). This distinction had just been formerly adopted by St. Thomas Aquinas in his
Summa Theologica. A further distinction is between
ens increatum and
ens creatum, i.e., uncreated being and created, or creaturely, being. A final distinction is between being as
actus purus and being as
ens potentiale, i.e., being as pure actuality and being as potential being. Suárez decided in favor of the first classification of the being into
ens infinitum and
ens finitum as the most fundamental, in connection with which he accords the other classifications their due. In the last disputation 54 Suárez deals with
entia rationis (beings of reason), which are impossible intentional objects, i.e. objects that are created by our minds but cannot exist in actual reality.
Theology In theology, Suárez attached himself to the doctrine of
Luis Molina, the celebrated Jesuit professor of Évora. Molina tried to reconcile the doctrine of
predestination with the freedom of the human will and the predestinarian teachings of the
Dominicans by saying that the predestination is consequent upon God's foreknowledge of the free determination of man's will, which is therefore in no way affected by the fact of such predestination. Suárez endeavoured to reconcile this view with the more orthodox doctrines of the efficacy of grace and special election, maintaining that, though all share in an absolutely sufficient grace, there is granted to the elect a grace which is so adapted to their peculiar dispositions and circumstances that they infallibly, though at the same time quite freely, yield themselves to its influence. This mediatizing system was known by the name of "congruism."
Philosophy of law Here, Suárez's main importance stems probably from his work on
natural law, and from his arguments concerning
positive law and the status of a
monarch. In his massive work,
Tractatus de legibus ac deo legislatore (1612), he is to some extent the precursor of
Grotius and
Pufendorf, in making an important distinction between natural law and international law, which he saw as based on custom. Though his method is throughout scholastic, he covers the same ground, and Grotius speaks of him with great respect. The fundamental position of the work is that all legislative as well as all paternal power is derived from God, and that the authority of every law stems ultimately from God's eternal law. Suárez denies the patriarchal theory of government and the divine right of kings founded upon it, doctrines popular at that time in England and to some extent on the Continent. He argued against the sort of
social contract theory that became dominant among early-modern
political philosophers such as
Thomas Hobbes and
John Locke, but some of his thinking, as transmitted by Grotius, found echoes in later liberal political theory. He argued that human beings have a social nature bestowed upon them by God, and this includes the potential to make laws. However, when a political society is formed, the authority of the state is not of divine but of human origin; therefore, its nature is chosen by the people involved, and their natural legislative power is given to the ruler. Because they gave this power, they have the right to take it back and to revolt against a ruler, only if the ruler behaves badly towards them, and they must act moderately and justly. In particular, the people must refrain from killing the ruler, no matter how tyrannical he may have become. If a government is imposed on people, on the other hand, they have the right to defend themselves by revolting against it and even kill the tyrannical ruler. Though Suárez was greatly influenced by Aquinas in his philosophy of law, there are some notable differences. Aquinas broadly defined "law" as "a rule and measure acts, whereby man is induced to act or is restrained from acting" (ST 1–11, qu. 90, art. 1). Suárez argues that this definition is too broad, since it applies to things that are not strictly laws, such as unjust ordinances and counsels of perfection. Suárez also takes issue with Aquinas' more formal definition of "law" as "an ordinance of reason for the common good, made by him who has care of the community, and promulgated" (ST 1–11, qu. 90, art. 4). This definition, he claims, fails to recognize that law is primarily an act of will rather than an act of reason, and would wrongly count orders to particular individuals as being laws. Finally, Suárez disagrees with Aquinas's claim that God can change or suspend some of the secondary precepts of the natural law, such as the prohibitions on murder, theft, and adultery (ST 1–11, qu. 94, art. 5). Suárez argues that the natural law is immutable as long as human nature remains unchanged, and that what may appear to be divinely-made changes in the natural law are really just alterations of subject matter. For example, when God orders Hosea to take a "wife of fornications" (i.e., have sex with a prostitute), this is not an exemption from God's prohibition of adultery. "For God has power to transfer to a man
dominium over a woman without her consent, and to effect such a bond between them that, by virtue of this bond, the union is no longer one of fornication." In 1613, at the instigation of
Pope Paul V, Suárez wrote a treatise dedicated to the Christian princes of Europe, entitled
Defensio catholicae fidei contra anglicanae sectae errores ("Defense of the Universal Catholic Faith Against the Errors of the Anglican Sect"). This was directed against the
oath of allegiance which
James I required from his subjects. James (himself a talented scholar) caused it to be burned by the common hangman and forbade its perusal under the 'severest penalties, complaining bitterly to
Philip III of Spain for harbouring in his dominions a declared enemy of the throne and majesty of kings. == Influence ==