The Period of Patristic Philosophy

The Patristic Period extends from the second century through the eighth century. The numerous writers of this age are called Church Fathers because they are sure guides in the interpretation of Christian truths.

The Fathers of the Church were also philosophers, but with the exception of St. Augustine, not one of them was overly preoccupied with philosophy. Hence the Patristic Age may be divided into three periods: Pre-Augustinian Augustinian Post-Augustinian.


This period includes the second and the third century, and the first half of the fourth century.

Second Century

The Church Fathers of the second century are classified as apologists and controversialists. By apologists are meant writers who proposed the truth of Christianity and defended them against the calumnious reports of pagans. Such are Aristides of Athens, Athenagoras, Minucius Felix, and Justin Martyr. Justin Martyr tried to prove that everything that is true and great in Greek philosophy is Christian. Other writers are called controversialists because they tried to refute the various heresies which appeared in the second century. Among these heresies the most important was Gnosticism which, although presented in different forms, is always basically the same in the attempt to empty religion of its supernatural content and to reduce the dogmas of Christianity to physical events.

Third Century

The third century is important because of the Christian School of Alexandria (the Didascalion) and also because of great apologies by writers of Western Africa. The Didascalion was founded by Pantaenus to prepare neophytes to receive baptism. But because of the attacks of the Neo-Platonic philosophers, who taught in the same city, the Didascalion became the seat of a hotly philosophical culture.

The most representative thinkers are: Clement of Alexandria (c.150-220 A.D.), who tried to show how Greek philosophy contributed to making the Christian more convinced of the truths of religion; Origin (c. 185-254 A.D.), a voluminous writer, considered to be the first systematizer of theology, who enjoyed a very wide fame; but because of latent errors about the creation of the world, the human soul, and the nature of evil, his fame gradually declined.

The Latin Apologists

The Fathers of Latin Africa, concentrated in Carthage, had a predilection for practical problems. Their attitude toward philosophy is not only one of negligence, but at times is even hostile, since they see in philosophy the danger of heresy. The most outstanding of them is Tertullian: The Gospel and the Academy have nothing in common; truth is given to us by the former, while the latter loses itself in empty rationalizations.

The First Half of the Fourth Century

During the first half of the fourth century there were many heresies regarding the divinity of Christ. In defense of Catholic truth, there arose a numerous host of Fathers, among them St. Athanasius, St. Cyril, St. Gregory of Nazianzus, St. Gregory of Nyssa, St. Basil and many others. It is the function of Church history to expose the various heresies and to justify their condemnation. According to Church authorities, in the matter of the heresies the authority of the Fathers is very great. In regard to philosophy, we may say that the Fathers were concerned with it only occasionally.

II. The Augustian Period: Reason and Faith

St. Augustine (354 - 430)

The basic characteristic of Augustine's thought is that man needs reason and faith to find truth. Augustine (picture) was led to this conclusion by his personal experience. Another basic characteristic consists in his "interiority." Augustine never ceases to look inside his soul; for in the soul he finds the fundamental principles of knowledge. How do we reach these principles? Illumination is the answer of Augustine. The human soul sees the intelligibles in a certain incorporeal light as the corporeal eye sees material objects in a corporeal light.

Augustine's Doctrines

Augustine even after his conversion to Catholic Christianity remained a Platonist. This adherence does not signify mere acceptance; but, just as Thomas Aquinas presented the doctrine of Aristotle as the rational basis of religion, so Augustine established the teaching of Plato and the Platonists. Philosophy is considered by Augustine as the science for the solution of the problem of life; hence he is more concerned with religious and moral problems than with those of pure speculation.

Theory of Knowledge

For Augustine the question of knowledge involves two problems: one regarding the existence of the subject, the other regarding the origin of concepts. He resolves the first question with the famous argument: "If I doubt, I exist"; he resolves the second by appealing to illumination, i.e., the belief that the eternal truths are imparted to our soul by the Word of God. Augustine, as a Platonist, underrates sense knowledge. More about St. Augustine's Illumination.


God: The existence of God is proved: (1) a priori, by the presence of eternal truths, which take their origin from the Eternal and Necessary Being; (2) a posteriori, by the imperfection and change of beings, a fact which presupposes a perfect and unchangeable being. Regarding the nature of God, Augustine holds that God is being, knowledge and love, the three attributes which are revealed also in every created being.


The world was created by God from nothing. With regard to the manner in which creation was effected, Augustine is inclined ti admit that in the beginning there were created a few species of beings, which, by virtue of the rationes seminales, gave origin to the other species down to the present state of the world. For Augustine "time" is founded in movement, and its reality is in the intellective memory.


Augustine, as a Platonist, considers the union of the soul with the body rather extrinsic. Regarding the origin of the soul, he hesitated between creationism and traducianism, but inclined toward the latter for controversial reasons. The faculties of the soul are three: memory, intellect and will; the will is free and superior to the intellect. Along with the question of liberty, there is the problem of the presence of evil. For Augustine, evil is essentially a "privation"; the privation of a due physical perfection makes physical evil, and the privation of moral perfection makes moral evil. The cause of moral evil is neither God nor matter, but the free will, which as such is able to deviate from the right order. Suffering, whether physical or moral, is the consequence of evil.

Liberty and Grace

Augustine sustained a long debate against Pelagianism. Pelagius held that human nature has not been corrupted by original sin and therefore is able of itself to attain the supernatural perfection due to it. Against this heresy, Augustine defended the absolute necessity of grace in order to attain the perfection due to man. How the efficacy of grace is to be reconciled with liberty is a question which disturbed the mind of Augustine, who at times neglected liberty to uphold the necessity and efficacy of grace.


Besides what has been said of free will and moral evil, it must be noted that Augustine holds the primacy of the will over the intellect. Every good work is an action of love.

Politics: "The City of God"

"The City of God" is a philosophical classic by which Augustine shows the history of good and evil working among mankind as a consequence of original sin and the Redemption through Jesus Christ. He wrote it while the Roman empire was falling into ruin under the barbarian invasions and the Church was rising from the imperial remains. In The Radical Academy Bookstore Books by and about St. Augustine On the Internet "Confessions" by St. Augustine "City of God" by St. Augustine

The positive contributions of St. Augustine to the Perennial Philosophy

St. Augustine affirms that the world was created by God from nothing, through a free act of His will. Time is a being of reason ("rens rationis") with a foundation in things which through becoming offer to the mind the concept of time as past, present, and future. Augustine affirms the absolute unity and the spirituality of the human soul. In regard to the nature of the soul he affirms that the soul is simple and immortal. Then sensitive soul, besides having the five senses, is endowed also with a sensitive cognition which is common to animals and which judges the proper object of each of the senses. The intellective soul has three functions: being, understanding, and loving, corresponding to three faculties: intellective memory, intelligence, and will. The primary among these three faculties is given to the will, which in man signifies love. The will of man is free.

Three kinds of evil can be distinguished: metaphysical, physical, and moral, and each of them consists in a deficiency in being, a descent toward non-being. Metaphysical evil is the lack of a perfection not due to a given nature and hence is not actually an evil. Under this aspect, all creatures are evil because they fall short of full perfection, which is God alone. Physical evil consists in the privation of a perfection due to nature, e.g., blindness is the privation of sight in a being which ought to have sight according to the exigencies of its nature. The only true evil is moral evil; sin, an action contrary to the will of God.

The cause of moral evil is not God, who is infinite holiness, nor is it matter, as the Platonists would have it, for matter is a creature of God and hence good. Neither is the will as a faculty of the soul evil, for it too has been created by God. The cause of moral evil is the faculty of free will, by which man is able to deviate from the right order, to oppose himself to the will of God. Such opposition gives moral evil reality -- negative, metaphysical reality in the sense of decadence of the order established by God, and hence decadence of being or descent toward non-being. Sin, from the very fact it is decadence of being, carries in itself its own punishment. By sinning man injures himself in his being, for he falls from what he ought to be. As a result of this fall there exist the sufferings which he must bear, such as remorse in the present life.

III. The Post-Augustian Period

The period which runs from the death of Augustine to the beginning of the ninth century is of no special interest in philosophy. The cause of this decadence can be summed up thus: The fall of the Roman empire and the consequent barbarian domination; The engagement of the Church in the works of the apostolate and charity and not in the field of speculation. Nevertheless, several men are worthy of mention: Severinus Boethius, who wrote commentaries on some works of Aristotle, which were widely used as textbooks during the Middle Ages; Cassiodorus, who worked unsuccessfully for the unification of the barbarians and Latins; Above all, St. Benedict of Nursia, the founder of monasticism in Western Europe.

The Order of St. Benedict spread throughout Europe and helped immensely to save Western culture from complete destruction.



The period of Christian thought extending from the beginning of the ninth century to the end of the fifteenth has come to be known as Scholasticism, a name taken from the school of philosophy of the University of Paris.


Patristic philosophy reached its climax in the system of Augustine; it was the last great product of classical-Christian civilization. When the Roman empire fell, the only institution that was capable of standing for law and order was the Church. The Goths sacked Rome but respected the Church and offered it protection. The literature and culture of Greece and Rome became almost extinct; the barbarous tribes initiated the Dark Ages. The only philosophy that survived was that which filtered through the writings of the Church Fathers. From Augustine to the ninth century learning consisted of an ecclesiastical dogmatism which was spiritually lifeless and it did little better than preserve the traditions of past; Plato and Aristotle were only partially known.

Scholastic philosophy means an organized system of truths which are distinct from the dogmas of faith but not opposed to them. This separation and coordination of reason and faith is not found in all Scholastic philosophy, but only during the period of its greatest splendor achieved under Thomas Aquinas. Scholastic philosophy, then, may be divided into: The formative period, extending from the beginning of the ninth century to the middle of the thirteenth; The period of maturity, extending a little more than half a century and covering Thomas Aquinas and John Duns Scotus; The period of decadence, extending from the death of Scotus to the end of the fifteenth century.

The Carolingian Revival of Learning

During the period of decadence, following the fall of the Roman empire, culture was restricted to ecclesiastical schools. There were of three types: Monastic schools, whose purpose was the formation of monks; Episcopal schools, whose purpose was the formation of priests, and occasionally of laymen; Parish schools, which were for the instruction of the faithful in respect to the reception of the sacraments.

It is to Charlemagne's credit to have undertaken the program for the establishment of schools. He summoned the monk Alcuin and entrusted him with the work of organizing the schools. Alcuin reformed the program of studies by establishing the divisions known as the trivium (comprising grammar, rhetoric and dialectic) and the quadrivium (arithmetic, geometry, astronomy and music). He established the "scola palatina." Other schools following the program of Alcuin were opened at Tours, Laon, Orleans and Fulda. This cultural movement had no development of any importance after the death of Charlemagne.

On the Internet Texts and Archives of Scholasticism

II. The Formative Period Of Scholastcism

The formative period of Scholasticism (the ninth, tenth, eleventh, twelfth centuries and the first half of the thirteenth century) developed under the influence of St. Augustine's thought. During this period, because of the prejudice of illumination, it was impossible to have a complete separation of reason from faith. Both mystics and dialecticians consider the intellect as unable to reason without being enlightened by God. With the help of illumination the intellect will be able to penetrate the content of the mysteries of faith. This period can be divided as follows: The ninth and the tenth century (John Scotus Erigena and the problem of universals); The eleventh and twelfth century (mystics and dialecticians); The first half of the thirteenth century (the question concerning the works of Aristotle).

a. The Ninth and Tenth Centuries

  1. John Scotus Erigena (815? - 877): Scotus Erigena wrote "De Divisione Naturae," a Neo-Platonic work. According to Erigena, Unity (God) descends into multiplicity, and multiplicity returns to Unity. The degrees of reality are the following: (1) creating, non-created Nature -- God, the Father; (2) created and creating Nature -- the Son; (3) created and non-creating Nature -- the sensible world informed by the Holy Spirit; (4) non-created and non-creating Nature -- God Himself as final cause. The first and fourth degrees coincide with God.

  2. The Problem of the Universals: What is the value of concepts, which are universal, in relation to real things, which are particular? Four solutions were attempted: Transcendent realism (the Platonic solution); Immanent realism ( the Aristotelian solution); Conceptualism (the concepts are mental signs without basis in reality); Nominalism (the concepts are names, speech).

See also Dr. Jonathan Dolhenty's essay on The World of Universals.

b. The Eleventh and Twelfth Centuries

At the beginning of the eleventh century the Churchmen showed a renewed interest in a better understanding of the truths of religion. The thinkers of that time are divided into mystics and dialecticians. Both feel the influence of illumination, and hence consider knowledge a gift of God. Faith is thus presupposed and is considered superior to reason. Nevertheless thinkers disagree in determining what is the contribution that reason can make to faith. The mystics see in philosophy a remnant of paganism and the danger of heresy. St. Peter Damian, St. Bernard of Clairvaux and the Victorines are mystics. The dialecticians, on the contrary, think that once the understanding of religious truths is required reason can be invoked to penetrate the very content of the mysteries of the faith. St. Anselm and Peter Abelard are dialecticians.

St. Anselm (picture) is well known for this ontological argument for the existence of God, as presented in the "Proslogium": The concept which everyone has of God is that of a most perfect being; Greater being cannot be conceived; Consequently, God must also really exist; otherwise He would no longer be that most perfect being, for He would lack real existence.

This argument, however, marks an illicit passage from the concept to reality. But, granted the doctrine of illumination, it would be valid. Abelard is the most complex personality of this time. He attempted to penetrate the mysteries of faith through reason, and found in St. Bernard his strongest opponent. In the question of universals, Abelard is considered a nominalist; but he possibly may not be such, as his vocabulary is not absolutely clear.

On the Internet "Proslogium" by Anselm Anselm: Philosophers' Criticisms of Anselm's Ontological Argument for the Being of God More about Peter Abelard "History of My Calamities" by Peter Abelard.

c. The First Half of the Thirteenth Century

  1. The Establishing of Universities: As a consequence of the interest in studies, some ecclesiastical schools were reinvigorated and rose to great fame. This is the origin of many universities; the most celebrated of them is the University of Paris, then Oxford University. While the universities were being organized, two religious Orders -- namely, the Franciscans and Dominicans -- obtained the faculty to teach in them, and made a large contribution to the development of Scholastic philosophy.

  2. The Discovery of the Works of Aristotle: The major factor in the development of Scholastic was the discovery of the works of Aristotle, which happened during the first half of the thirteenth century. These works first reached the universities through the commentaries of Jewish and Arabian philosophers.

Among the famous commentators on Aristotle in Spain were two Jewish philosophers, Avicebron (died about 1058), and Maimonides (died 1204) (picture). The Arabian physician Avicenna (picture) enjoyed greater fame. He attempted to reconciled Aristotle with the religion of Islam, and hence affirmed the immortality of the soul.

The most famous commentator was the Spanish-Arabian philosopher Averroes (1126-1198) (picture). He too was a physician and Thomas Aquinas gave him the designation "The Commentator."

Later what was called the "translatio nova" of Aristotle, made directly from the Greek, was attempted. The attitude of thinkers in regard to the works of Aristotle was threefold: Some thinkers advocated the integral acceptance of the system of Aristotle -- the most representative of this group was Siger of Brabant; Others accepted Aristotle's opinions when these were not opposed to St. Augustine -- the most representative of this group is St. Bonaventure; Yet others -- among them, Thomas Aquinas, who accepted the system of Aristotle critically -- discarded the theories of the philosopher in those points which were not in accord with Christianity.

Siger of Brabant (died about 1281) in his work "De Anima Intellectiva" holds the theory that the world is eternal, denies providence, and admits the existence of the acting intellect as something separate and the same for all men. Siger defended himself by having recourse to the principle of the double truth.

III. The Godlden Age Of Scholastic Philosophy

St. Bonaventure (1221 - 1274)

St. Bonaventure (picture) wished to theorize on the life of St. Francis, and to build it into a perfect system of the Christian life. Bonaventure, therefore, is not opposed to the doctrine of Aristotle; but his preference is for St. Augustine, in whose doctrine, as in the practical life of St. Francis, the external and the internal world speak to us of God.


  1. Theory of Knowledge: Bonaventure admits three degrees of knowledge: Knowledge of the particular, of sensitive objects; Knowledge of ideas, which come from illumination; Contemplation, the understanding of divine things.

  2. Metaphysics: Bonaventure accepts the Aristotelian principle of matter and form, but wanders far afield in the interpretation of both. Matter has its own form, and contains the seeds of all determinations; there is corporeal matter as well as incorporeal matter. The existence of God is proved a priori (argument of St. Anselm). In every finite being there is a plurality of forms. In cosmology, Bonaventure holds that creation "ab aeterno" is contradictory; God, when He created matter, placed in it the seeds of all determinations. In psychology, Bonaventure's thesis is that the union of the soul with the body is extrinsic, because the soul is a complete substance in itself. In ethics, Bonaventure defends the priority of the will over the intellect.

On the Internet More about Bonaventure

St. Thomas Aquinas (1225 - 1274)

For a more advanced & comprehensive discussion, see: The Philosophical System of Thomas Aquinas, by Maurice de Wulf.

Philosophy and Theology

Thomas Aquinas (picture) does not accept the Averroist principle of the double truth. Philosophy and theology are distinct but not opposed, and what reason shows to be true is absolutely true in theology also. Moreover, Aquinas does not accept Augustinian illumination, the belief that the eternal truths are imparted to our soul by the Word of God. For Aquinas the intellect is able to reach concepts through abstraction. The proper object of the human intellect is this visible world; our intellect cannot penetrate the mysteries of faith. Nevertheless, the most important religious truths, such as the existence of God and the immortality of the soul, are both the object of reason and the object of faith.

Theory of Knowledge

Knowledge is obtained through two stages of operations, sensitive and intellective, which are intimately related to one another. The object of sensitive knowledge is the particular thing, while the object of the intellect is the "intelligible," which is arrived at from the particular by abstraction. The intellect has three operations: abstraction, judgment and reasoning.

General Metaphysics: Aquinas accepts the general principles of Aristotle's metaphysics, in which being is a created composite of potency and act. The general principle of potency and act, applied to those beings in which it is already existent, is specified in a second principle, the principle of matter and form. The principle of individuation is "matter signed by quantity."


Aquinas does not admit supernatural Augustinian illumination, and hence refuses to accept any proof a priori of the existence of God (argument of St. Anselm). The arguments for the existence of God must be a posterior, and they are solidly certain. Aquinas has presented five different ways in which the intellect can prove the existence of God; each of them consists in a fact of experience, which can be justified only by the existence of the transcendent Being (God). Thus: The fact of motion induces the mind to affirm the existence of the immovable Mover; The fact of the production of a new reality demands the existence of the uncaused reality; The fact of a contingent being implies the existence of a necessary Being; The fact of the existence in things, to a greater or lesser degree, of the good, the true, and the noble, implies the existence of "absolute perfection"; The Fact of the order of the whole universe implies the necessity of an Intelligence which is the cause of this order.


In cosmology, Aquinas departs from the dualism of Aristotle; matter is created by God. The whole universe was created by an act of the free will of God, and what happens in the universe finds its counterpart in the wisdom of God.

The Soul: When the form in matter is the origin of immanent actions, it is called soul. Hence there is a vegetative soul, a sensitive soul, and an intellective soul. The human soul is directly created by God, and it is the true form of the body; it therefore performs both organic and inorganic activities. The intellect is an inorganic power of the individual soul. The agent intellect is not one and the same for all but is the human soul itself in so far as the soul is intellectual in nature. As such it is able to abstract the intelligibles from material conditions. Since the human soul is able to perform inorganic operations, it is immaterial, spiritual and immortal.

Ethics and Politics

In opposition to the voluntarism of St. Augustine, Aquinas upholds the primacy of the intellect over the will. Aquinas extends this law even to God; the foundation of creation is the Divine Essence, which is rational; the present order of creation has been willed by God because it was rational. All created beings must follow the natural law, and for rational beings, including man, it is the law of reason. Man is free, and he can abuse his freedom; but every abuse of freedom is an irrational act.


departs from Augustinianism also in his doctrine on the state; society is natural to man, and not a consequence of the original fall, as the Augustinians believed. The first step to society is the family and the end of society is the common material good of men. Civil society, therefore, must recognize another superior society, that is, the Church, to which has been entrusted the spiritual good citizens.

John Duns Scotus (1265 - 1308) "The Subtle Doctor"

John Duns Scotus (picture) is the champion of Franciscan Augustinianism. Nevertheless he abandons certain theses of the Augustinian tradition, in favor of the new contributions of Aristotelianism.

Theory of Knowledge

Scotus does not admit Augustinian illumination. He distinguishes between the "proper" object of the intellect, and the object in "state of act." The immediate object of the intellect is the quiddity (essence) abstracted from material conditions; but the "proper" object is "being as being." In regard to abstraction, Scotus holds that the phantasm (sense image) concurs as a concause in the formation of the concept.

General Metaphysics

Scotus accepts the Aristotelian principles of matter and form, but to these two elements he gives a different interpretation. Prime matter as such can exist; moreover, matter is a constitutive element of every being, even of those of spiritual nature, such as the angels. The principle of individuation, instead of being matter, as Thomas Aquinas taught, is form, in the opinion of Scotus. The determination of the form in the act of individuation is called "haecceitas." Moreover, the concept of being is not analogical, as Aquinas held, but univocal.


Scotus holds, in opposition to traditional Augustianism, that there is no intuition of God. His existence must be proved and Scotus proves the existence of God first a posteriori, by the traditional argument of change. But he admits also the validity of the ontological argument of St. Anselm, to which he gives a new interpretation by introducing into it another principle; that is, that the concept of infinite being is not contradictory, and hence the infinite Being exists. For Scotus the fundamental attribute of God is His infinity.


In this field Scotus accepts the common doctrine of Scholastic tradition. However, according to his principle of the primacy of the will over the intellect, he holds that creation is first an act of will. In consequence of this voluntaristic doctrine, many truths which for Thomas are demonstrable with certainty, are not so for Scotus.


In psychology Scotus admits that in every individual there is a multiplicity of forms. The human soul is a complete being in itself. The proper object of the intellect is being in its entire extension. The proof of the immortality of the human soul rests upon faith rather than upon reason. According to Scotus' principle of the primacy of the will, opposites in the field of contingency do not imply contradiction.


Scotus reaffirms his voluntarist doctrine in his ethics; this means that God finds within His will the motives for realizing one series of possibles rather than another. The will of God does not act capriciously, however, for God's will is at the same time the most intelligent act. Thus, all that is essentially bound up with the essence of God is also essentially bound up with the divine will, as, for example, the principle of contradiction and the first three commandments of the Decalogue. What is not necessarily bound up with the Divine Essence is dependent upon the free choice of God. Scotus, with St. Augustine, affirms that virtue is an act of love which directs us to God.


Dogmas, according to Scotus, are beyond dispute; faith is basic to truth; love is the fundamental virtue; faith and love are based on the will; will is superior to the intellect. Universals exist before things, as forms in the mind of God; and after things, as abstract concepts in the human mind. Universal nature (or essence) is supplemented by individual nature and the principle of difference is individuation. General concepts (universals) finally bring us to individuals (nominals, particulars). Duns Scotus agrees with Aquinas in many points; his major difference is in his emphasis on the will, discounting the supreme importance of the intellect in Aquinas' philosophy; Scotus made the will supreme. This difference between the two concepts of the will led to the Thomist-Scotist controversy.