The Summa Theologica is the most famous work of St. Thomas Aquinas. It was intended as a manual for beginners as a compilation of all of the main theological teachings of that time. It is not designed or ordered as an apologetic work, to convince non-Catholics, but it does contain a summary of the reasonings for almost all points of the Catholic faith.
The Summa Theologica is a more mature and structured version of an earlier work of St. Thomas: the Summa Contra Gentiles. This former work was more apologetic in nature, and each article was a refutation of a specific belief of different heresies and other religions.
The Summa has a standard format for each article. At the top, a question is posed, such as "Whether it was fitting for Jesus to be poor." Then a series of objections are listed to try and prove the opposite. One objection for example could be "The Philosopher (Aristotle) says that the best life is being in the middle, between poor and rich." Then a short counter statement, which would take the exact opposite point of view, would come, such as "the bible says that God always does the right thing, but Jesus was God, and he was poor, so it must have been the right thing." Then the actual truth is presented, which is not usually one side or the other, but a clarification of the whole issue. This would be something like "although its true that the best way of life is a middle ground between being poor and rich, the reason for this is that this allows a person to be not distracted from his goal by either want or luxury. But the goal of Jesus was to spread his message as far as possible, and so to be the most mobile, it was better to have nothing." Then indivdual counters to the first objections are made, if needed.
The Summa makes many refrences to certain thinkers which were held in great respect in St. Thomas's time. Almost the entire Summa is based off certain quotes from these authors, although many points made by them are refuted. Some were called by special names:
- The Philosopher: Aristotle. He was considered the best philosopher, the one who had expressed the most truth at his time. The main aim of the Scholastic theologians were to use his precise technical terms and logical system to describe theology.
- The Master: St. Peter Lombard. He was the man who wrote the main textbook for theology at the time, called the sentences. These were commentaries on the writings of the Doctors of the Church.
- St. Augustine: Considered the greatest theologian who had ever lived at the time, St. Augustine's works are frequently quoted by St. Thomas Aquinas
- Dionysius: This man was the second most read father of the Church at the time, although today there is controversy over the real authorship of his writings.
- Rabbi Noah: Rabbi Noah was a Jewish rabbi who wrote after Jesus Christ. Nevertheless, the scholastics found many insights from his works.
- Theology is a science, the greatest of all the sciences, and the most certain (since its source is from God who knows everything)
- The existence of God, his total simplicity or lack of composition, his eternal nature, his knowledge, the way his will operates, and his power can all be proved by human reasoning alone, by anyone and at anytime.
- Unbelief is the greatest sin
- The principles of Just War
- Defense attorneyss can not defend a person they know to be guilty
- Taking interest on loans is forbidden, because it is charging people twice for the same thing
- In and of itself, selling a thing for more or less then its worth is unlawful
- Martyrs, Teachers of the faith (doctors), and Virgins receive special crowns in heaven for their achievements, in that order
- Homosexuality is worse then rape, because it goes against nature designed by God, and in that way is a more direct assault against God
- The contemplative life is greater then the active life, but greater still is the contemplative life that sometimes takes actions to call others to the contemplative life and give them the fruits of contemplation (this actually was the lifestyle of the Dominican monks that St. Thomas was a part of)
- Being a monk is greater then being married, even greater in many ways then being a Priest, although not as good as being a Bishop. Both monks and Bishops are in a state of perfection
- If a person has a spell put on them to cause them to get married, that marriage is invalid
- The natural desire of the soul or mind is to understand the essence of something, the greatest happiness of all, the happiness of heaven, consists of seeing the essence of God.
- Although the Jews delivered Christ to die, it was the Gentiles who killed him, symbolizing how salvation started with the Jews, but then was spread to the Gentiles.
- Its always a good thing to become a monk or a nun, everyone is called to do it, its easier then being married, children should do it, no parents can bar children from doing it, everyone should encourage it, no deliberation is required to figure out if you should be one, its absolutely false to say only already holy people should become monks or nuns.
- Those who voluntarily practice poverty will be assistant judges at the final judgement: "(Job 36:6): "He saveth not the wicked, and He giveth judgment to the poor.""
Text to integrate from Schaff-Herzog Encyc of Religion:
4. The Summa, Part i.; Theology The greatest work of Thomas was the Summa and it is the fullest presentation of his views. He worked on it from the time of Clement IV. (after 1265) until the end of his life. When he died he had reached question ninety of part iii., on the subject of penance. What was lacking was afterward added from the fourth book of his commentary on the "Sentences" of Peter Lombard as a supplementum, which is not found in manuscripts of the thirteenth and fourteenth centuries. The Summa was translated into Greek (apparently by Maximus Planudes, c. 1327), into Armenian, into many European tongues, and even into Chinese.
It consists of three parts. Part i. treats of God, who is the "first cause, himself uncaused" (primum movens immobile) and as such existent only in act (actu), that is pure actuality without potentiality and, therefore, without corporeality. His essence is actus purus et perfectos. This follows from the fivefold proof for the existence of God; namely, there must be a first mover, unmoved, a first cause in the chain of causes, an absolutely necessary being, an absolutely perfect being, and a rational designer. In this connection the thoughts of the unity, infinity, unchangeableness, and goodness of the highest being are deduced. The spiritual being of God is further defined as thinking and willing. His knowledge is absolutely perfect since he knows himself and all things as appointed by him. Since every knowing being strives after the thing known as end, will is implied in knowing. Inasmuch as God knows himself as the perfect good, he wills himself as end. But in that everything is willed by God, everything is brought by the divine will to himself in the relation of means to end. Therein God wills good to every being which exists, that is he loves it; and, therefore, love is the fundamental relation of God to the world. If the divine love be thought of simply as act of will, it exists for every creature in like measure: but if the good assured by love to the individual be thought of, it exists for different beings in various degrees. In so far as the loving God gives to every being what it needs in relation to the whole, he is just: in so far as he thereby does away with misery, he is merciful. In every work of God both justice and mercy are united and, indeed, his justice always presupposes his mercy, since he owes no one anything and gives more bountifully than is due. As God rules in the world, the "plan of the order of things" preexists in him; i.e., his providence and the exercise of it in his government are what condition as cause everything which comes to pass in the world. Hence follows predestination: from eternity some are destined to eternal life, while as concerns others "he permits some to fall short of that end." Reprobation, however, is more than mere foreknowledge; it is the "will of permitting anyone to fall into sin and incur the penalty of condemnation for sin." The effect of predestination is grace. Since God is the first cause of everything, he is the cause of even the free acts of men through predestination. Determinism is deeply grounded in the system of Thomas; things with their source of becoming in God are ordered from eternity as means for the realization of his end in himself. On moral grounds Thomas advocates freedom energetically; but, with his premises, he can have in mind only the psychological form of self-motivation. Nothing in the world is accidental or free, although it may appear so in reference to the proximate cause. From this point of view miracles become necessary in themselves and are to be considered merely as inexplicable to man. From the point of view of the first cause all is unchangeable; although from the limited point of view of the secondary cause miracles may be spoken of. In his doctrine of the Trinity Thomas starts from the Augustinian system. Since God has only the functions of thinking and willing, only two processiones can be asserted from the Father. But these establish definite relations of the persons of the Trinity one to another. The relations must be conceived as real and not as merely ideal; for, as with creatures relations arise through certain accidents, since in God there is no accident but all is substance, it follows that "the relation really existing in God is the same as the essence according to the thing. "From another side, however, the relations as real must be really distinguished one from another. Therefore, three persons are to be affirmed in God. Man stands opposite to God; he consists of soul and body. The "intellectual soul" consists of intellect and will. Furthermore the soul is the absolutely indivisible form of man; it is immaterial substance, but not one and the same in all men (as the Averrhoists assumed). The soul's power of knowing has two sides; a passive (the intellectus possibilis) and an active (the intellectus agens). It is the capacity to form concepts and to abstract the mind's images (species) from the objects perceived by sense. But since what the intellect abstracts from individual things is a universal, the mind knows the universal primarily and directly, and knows the singular only indirectly by virtue of a certain reflexio (cf. SCHOLASTICISM). As certain principles are immanent in the mind for its speculative activity, so also a "special disposition of works;" or the synderesis (rudiment of conscience), is inborn in the "practical reason," affording the idea of the moral law of nature, so important in medieval ethics.
5. The Summa, Part ii.; Ethics The first part of the Summa is summed up in the thought that God governs the world as the "universal first cause." God sways the intellect in that he gives the power to know and impresses the species intelligibiles on the mind, and he sways the will in that he holds the good before it as aim, and creates the virtus volendi. "To will is nothing else than a certain inclination toward the object of the volition which is the universal good." God works all in all; but so that things also themselves exert their proper efficiency. Here the Areopagitic ideas of the graduated effects of created things play their part in Thomas's thought. The second part of the Summa (two parts, prima secundae and secundae seconda) follows this complex of ideas. Its theme is man's striving, after the highest end, which is the blessedness of the visio beata. Here Thomas develops his system of ethics, which has its root in Aristotle. In a chain of acts of will man strives for the highest end. They are free acts in so far as man has in himself the knowledge of their end and therein the principle of action. In that the will wills the end, it wills also the appropriate means, chooses freely and completes the consensus. Whether the act be good or evil depends on the end. The "human reason" pronounces judgment concerning the character of the end, it is, therefore, the law for action. Human acts, however, are meritorious in so far as they promote the purpose of God and his honor. By repeating a good action man acquires a moral habit or a quality which enables him to do the good gladly and easily. This is true, however, only of the intellectual and moral virtues, which Thomas treats after the manner of Aristotle; the theological virtues are imparted by God to man as a "disposition," from which the acts here proceed, but while they strengthen, they do not form it. The "disposition" of evil is the opposite alternative. An act becomes evil through deviation from the reason and the divine moral law. Therefore, sin involves two factors: its substance or matter is lust; in form, however, it is deviation from the divine law. Sin has its origin in the will, which decides, against the reason, for a "changeable good." Since, however, the will also moves the other powers of man, sin has its seat in these too. By choosing such a lower good as end, the will is misled by self-love, so that this works as cause in every sin. God is not the cause of sin, since, on the contrary, he draws all things to himself. But from another side God is the cause of all things, so he is efficacious also in sin as actio but not as ens. The devil is not directly the cause of sin, but he incites by working on the imagination and the sensuous impulse of man, as men or things may also do. Sin is original. Adam's first sin passes upon himself and all the succeeding race; because he is the head of the human race and "by virtue of procreation human nature is transmitted and along with nature its infection." The powers of generation are, therefore, designated especially as "infected." The thought is involved here by the fact that Thomas, like the other scholastics, held to creationism, therefore taught that the souls are created by God. Two things according to Thomas constituted man's righteousness in paradise-- the justitia originalis or the harmony of all man's powers before they were blighted by desire, and the possession of the gratis gratum faciens (the continuous indwelling power of good). Both are lost through original sin, which in form is the "loss of original righteousness." The consequence of this loss is the disorder and maiming of man's nature, which shows itself in "ignorance; malice, moral weakness, and especially in concupiscentia, which is the material principle of original sin." The course of thought here is as follows: when the first man transgressed the order of his nature appointed by nature and grace, he, and with him the human race, lost this order. This negative state is the essence of original sin. From it follow an impairment and perversion of human nature in which thenceforth lower aims rule contrary to nature and release the lower element in man. Since sin is contrary to the divine order, it is guilt and subject to punishment. Guilt and punishment correspond to each other; and since the "apostasy from the invariable good which is infinite," fulfilled by man, is unending, it merits everlasting punishment.
But God works even in sinners to draw them to the end by "instructing through the law and aiding by grace." The law is the "precept of the practical reason." As the moral law of nature, it is the participation of the reason in the all-determining "eternal reason." But since man falls short in his appropriation of this law of reason, there is need of a "divine law." And since the law applies to many complicated relations, the practicae dispositiones of the human law must be laid down. The divine law consists of an old and a new. In so far as the old divine law contains the moral law of nature it is universally valid; what there is in it, however, beyond this is valid only for the Jews. The new law is "primarily grace itself " and so a "law given within," "a gift superadded to nature by grace," but not a "written law." In this sense, as sacramental grace, the new law justifies. It contains, however, an "ordering" of external and internal conduct, and so regarded is, as a matter of course, identical with both the old law and the law of nature. The consilia (see CONSILIA EVANGELICA) show how one may attain the end "better and more expediently" by full renunciation of worldly goods. Since man is sinner and creature, he needs grace to reach the final end. The "first cause" alone is able to reclaim him to the "final end." This is true after the fall, although it was needful before. Grace is, on one side, "the free act of God," and, on the other side, the effect of this act, the gratia infusa or gratia creata, a habitus infusus which is instilled into the "essence of the soul," "a certain gift of disposition, something supernatural proceeding from God into man." Grace is a supernatural ethical character created in man by God, which comprises in itself all good, both faith and love. Justification by grace comprises four elements: "the infusion of grace, the influencing of free will toward God through faith, the influencing of free will respecting sin, and the remission of sins." It is a "transmutation of the human soul," and takes place "instantaneously." A creative act of God enters, which, however, executes itself as a spiritual motive in a psychological form corresponding to the nature of man. Semipelagian tendencies are far removed from Thomas. In that man is created anew he believes and loves, and now sin is forgiven. Then begins good conduct; grace is the "beginning of meritorious works." Thomas conceives of merit in the Augustinian sense: God gives the reward for that toward which he himself gives the power. Man can never of himself deserve the prima gratis, nor meritum de congruo (by natural ability; cf. R. Seeberg, Lehrbuch der Dogmengeschichte, ii. 105-106, Leipsic, 1898). After thus stating the principles of morality, in the secunda secundae Thomas comes to a minute exposition of his ethics according to the scheme of the virtues. The conceptions of faith and love are of much significance in the complete system of Thomas. Man strives toward the highest good with the will or through love. But since the end must first be "apprehended in the intellect," knowledge of the end to be loved must precede love; "because the will can not strive after God in perfect love unless the intellect have true faith toward him." Inasmuch as this truth which is to be known is practical it first incites the will, which then brings the reason to "assent." But since, furthermore, the good in question is transcendent and inaccessible to man by himself, it requires the infusion of a supernatural "capacity " or "disposition" to make man capable of faith as well as love. Accordingly the object of both faith and love is God, involving also the entire complex of truths and commandments which God reveals, in so far as they in fact relate to God and lead to him. Thus faith becomes recognition of the teachings and precepts of the Scriptures and the Church ("the first subjection of man to God is by faith "). The object of faith, however, is by its nature object of love; therefore faith comes to completion only in love ("by love is the act of faith accomplished and formed").
6. The Summa, Part iii.; Christ Christ is the theme of part iii. It can not be asserted that the incarnation was absolutely necessary, "since God in his omnipotent power could have repaired human nature in many other ways ": but it was the most suitable way both for the purpose of instruction and of satisfaction. The Unio between the Logos and the human nature is a "relation" between the divine and human natures which comes about by their being brought together one person . An incarnation can be spoken of only in the sense that the human nature began to be in the eternal hypostasis of the divine nature. So Christ is unum since his human nature lacks the hypostasis. The person of the Logos, accordingly, has assumed the impersonal human nature, in such way that the assumption of the soul became the means for the assumption of the body. This union with the human soul is the gratia unionis which leads to the impartation of the gratia habitualis from the Logos to the human nature. Thus all human potentialities are made perfect in Jesus. Besides the perfections given by the vision of God, which Jesus enjoyed from the beginning, he receives all others by the gratia habitualis. In so far as the limited human nature receives these perfections, they are finite. This is true of both the knowledge and the will of Christ. The Logos impresses the species intelligibiles of all created things on the soul, but the intellectus agens transforms them gradually into the impressions of sense. The soul of Christ works miracles only as instrument of the Logos, since omnipotence in no way appertains to this human soul in itself. Christ's human nature was imperfect, to make his true humanity evident, and because he would bear the general consequences of sin for humanity. Christ experienced suffering, but blessedness reigned in his soul, which did not extend to his body. Concerning redemption, Thomas teaches that Christ is to be regarded as redeemer after his human nature but in such way that the human nature produces divine effects as organ of divinity. Christ as head of humanity imparts ordo, perfectio, and virtus to his members. He is the teacher and example of humanity; his whole life and suffering as well as his work after he is exalted serve this end. The love wrought hereby in men effects, according to Luke vii. 47, the forgiveness of sins.
Then follows a second complex of thoughts which has the idea of satisfaction as its center. God as the highest being could forgive sins without satisfaction; but because his justice and mercy could be best revealed through satisfaction he chose this way. As little as satisfaction is necessary in itself, so little does it offer an equivalent for guilt; it is a "superabundant satisfaction," since on account of the divine subject in Christ in a certain sense his suffering and activity are infinite. With this thought the strict logical deduction of Anselm's theory is given up. Christ's suffering bore personal character in that it proceeded "out of love and obedience." It was an offering to God, which as personal act had merit. Thereby Christ "merited" salvation for men. As Christ, exalted, still influences men, he still works on their behalf continually in heaven through intercession (interpellatio). In this way Christ as head of humanity effects the forgiveness of sins, reconciliation with God, immunity from punishment, deliverance from the devil, and the opening of heaven's gate. But inasmuch as all these benefits are already offered through the inner operation of the love of Christ, Thomas has combined the theories of Anselm and Abelard by joining the one to the other.
7. The Sacraments The doctrine of the sacraments follows the Christology; the sacraments "have efficacy from the incarnate Word himself." They are not only signs of sanctification, but bring it about. It is inevitable that they bring spiritual gifts in sensuous form, because of the sensuous nature of man. The res sensibiles are the matter, the words of institution the form of the sacraments. Contrary to the Franciscan view that the sacraments are mere symbols whose efficacy God accompanies with a directly following creative act in the soul, Thomas holds it not unfit to agree with Hugo of St. Victor that "a sacrament contains grace," or to teach that they "cause grace." Thomas attempts to remove the difficulty of a sensuous thing producing a creative effect, by distinguishing between the causa principalis et instrumentalis. God as the principal cause works through the sensuous thing as the means ordained by him for his end. "Just as instrumental power is acquired by the instrument from this, that it is moved by the principal agent, so also the sacrament obtains spiritual power from the benediction of Christ and the application of the minister to the use of the sacrament. There is spiritual power in the sacraments in so far as they have been ordained by God for a spiritual effect." This spiritual power remains in the sensuous thing until it has attained its purpose. At the same time Thomas distinguished the gratia sacramentalis from the gratia virtutum et donorum, in that the former perfects the general essence and the powers of the soul, whilst the latter in particular brings to pass necessary spiritual effects for the Christian life. Later this distinction was ignored. In a single statement, the effect of the sacraments is to infuse justifying grace into men. What Christ effects is achieved through the sacraments. Christ's humanity was the instrument for the operation of his divinity; the sacraments are the instruments through which this operation of Christ's humanity passes over to men. Christ's humanity served his divinity as instrumentum conjunctum, like the hand: the sacraments are instrumenta separata, like a staff; the former can use the latter, as the hand can use a staff. For a more detailed exposition cf. Seeberg, ut sup., ii. 112 sqq. Of Thomas' eschatology, according to the commentary on the "Sentences," this is only a brief account. Everlasting blessedness consists in the vision of God: and this vision consists not in an abstraction or in a mental image supernaturally produced, but the divine substance itself is beheld, and in such manner that God himself becomes immediately the form of the beholding, intellect; God is the object of the vision and at the same time causes the vision. The perfection of the blessed also demands that the body be restored to the soul as something to be made perfect by it. Since blessedness consists in operatio, it is made more perfect in that the soul has a definite operatio with the body, although the peculiar act of blessedness (i.e., the vision of God) has nothing to do with the body.
8. Estimation Aquinas's two most important qualities were his great talent for systematizing and his power of simple and lucid exposition. The work of preceding generations, especially of Alexander of Hales, had lightened the task of selection and ordering of the material; on the other hand, it had added to the number of problems and expanded the argument enormously, impairing the unity and clarity of the progress of thought. It was Thomas who made a single connected and consistent whole of the mass. His Aristotelianism, with its Neoplatonic elements, should also be noted. He owed not only his philosophical thoughts and world conception to Aristotle, but also the frame for his theological system; Aristotle's metaphysics and ethics dictated the trend of his system. Here he gained the purely rational framework for his massive temple of thought, namely of God, the rational cause of the world, and man's striving after him. Then he filled this in with the dogmas of the Church or of revelation. Nevertheless he succeeded in upholding church doctrine as credible and reasonable. The final characteristic of Thomas to be noted is his blameless orthodoxy. For opposition to Thomas and the reaction in the fifteenth century, see Scholasticism. This position as the teacher of the church grew stronger from Pope Leo X (1520) to Leo XIII (1900); even to-day the Roman Catholic Church preserves the inheritance of the ancient world-conception and the old church dogmas in the form which Thomas Aquinas gave them. For the relation of theology to philosophy and the sphere of the former and its sources, see Scholasticism.