The Summa and Its Parts

Many theologians and philosophers in St. Thomas’s time wrote Summas. A Summa is simply a summary. It is more like an encyclopedia than a textbook, and it is meant to be used more as a reference library than as a book. There is extreme economy in the use of words—no digressions and few illustrations. Everything is “bottom line.” Such a style should appeal to busy moderns.

The medievals had a passion for order, because they believed that God had a passion for order when He designed the universe. So a Summa is ordered and outlined with loving care.

Yet, though very systematic, a Summa is not a system in the modern sense, a closed and deductive system like that of Descartes, Spinoza, Leibnitz, or Hegel. It uses induction as well as deduction, and its data come from ordinary experience and divine revelation as well as philosophical axioms ("first principles").

A Summa is really a summarized debate. To the medieval mind, debate was a fine art, a serious science, and a fascinating entertainment, much more than it is to the modern mind, because the medievals believed, like Socrates, that dialectic could uncover truth. Thus a “scholastic disputation” was not a personal contest in cleverness, nor was it “sharing opinions"; it was a shared journey of discovery.

The “objections” from the other side are to be taken seriously in a Summa. They are not straw men to be knocked down easily, but live options to be considered and learned from. St. Thomas almost always finds some important truth hidden in each objection, which he carefully distinguishes from its error. For he believed not only that there was all truth Somewhere but also that there was some truth everywhere.

The structural outline of the Summa Theologica is a mirror of the structural outline of reality. It begins in God, Who is “in the beginning.” It then proceeds to the act of creation and a consideration of creatures, centering on man, who alone is created in the image of God. Then it moves to man’s return to God though his life of moral and religious choice, and culminates in the way or means to that end: Christ and His Church.

Thus the overall scheme of the Summa, like that of the universe, is an exitus-redditus, an exit from and a return to God, Who is both Alpha and Omega. God is the ontological heart that pumps the blood of being through the arteries of creation into the body of the universe, which wears a human face, and receives it back through the veins of a man’s life of love and will.

The structure of the Summa, and of the universe, is dynamic. It is not like information in a library, but like blood in a body.

It is essential to keep this “big picture” in mind when reading the Summa because there are so many details that it is tempting to focus on them and lose the sense of their place and order. St. Thomas never does that. His style is atomistic and “choppy,” but his vision is continuous and all-encompassing.

Why is the style so choppy? St. Thomas chops his prose into bite-sized segments for the same reason Mommy cuts Baby’s meat into bite-sized chunks. The Summa would lose much of its clarity and digestibility if it were homogenized into continuous, running prose, like watery stew. (A current British version has done just that.)

You say yes, I say no

The Summa Theologica is divided into four overall Parts (I, I–II, II–II, and III). Each Part is divided into Treatises (e.g., On the Creation, On Man, On Law). Each Treatise is divided into numbered “Questions,” or general issues within the topic of the treatise (e.g., “Of the Simplicity of God,” “Of the Angels in Comparison with Bodies,” “Of the Effects of Love"). Finally each “Question” is divided into numbered “Articles.”

The “Article” is the basic thought—unit of the Summa. What we mean in modern English by an “article"—an essay—is what St. Thomas means by a “Question,” and what we mean by a “question"—a specific, single interrogative sentence—is what he means by an “Article,” e.g., “Whether God Exists“ Whether the Inequality of Things Is from “Whether Sorrow Is the Same as Pain?”

Each Article begins by formulating in its title a single question in such a way that only two answers are possible: yes or no. St. Thomas does this, not because he thinks philosophy or theology is as simple as a true-false exam, but because he wants to make an issue finite and decidable, just as debaters do in formulating their “resolution.”

There are an indefinite number of possible answers to a question like “What is God?” If he had formulated his questions that way, the Summa might be three million pages long instead of three thousand. Instead, he asks, for example, “Whether God Is a Body?” It is possible to divide and demonstrate that one of the two possible answers (yes) is false and therefore that the other (no) is true.

Each “Article” has five structural parts. First, the question is formulated in a yes or no format, as explained above, beginning with the word “Whether” (Utrum).

Second, St. Thomas lists a number of Objections (usually three) to the answer he will give. The Objections are apparent proofs of this opposite answer, the other side to the debate. These objections begin with the formula: “It seems tha“ (Oportet).

These Objections must be arguments, not just opinions, for one of the basic principles of any intelligent debate (woefully neglected in all modern media) is that each debater must give relevant reasons for every controvertible opinion he expresses. The Objections are to be taken seriously, as apparent truth.

One who is seeking the strongest possible arguments against any idea of St. Thomas will rarely find any stronger ones, any more strongly argued, than those in St. Thomas himself. He is extremely fair to all his opponents. I think he descends to name-calling only once in the entire Summa, when he speaks of the “really stupid” idea of David of Dinant that God is indistinguishable from prime matter, or pure potentiality—an idea not very far from that of Hegel and modern “process theologians"!

Third, St. Thomas indicated his own position with the formula “On the contrar“ (Sed contra). The brief argument that follows the statement of his position here is usually an argument from authority, i.e., from Scripture, the Fathers of the Church, or recognized wise men.

The medievals well knew their own maxim that “the argument from authority is the weakest of all arguments.” But they also believed in doing their homework and in learning from their ancestors—two habits we would do well to cultivate today.

The fourth part, “I answer that” (Respondeo dicens), is the body of the Article. In it, St. Thomas proves his own position, often adding necessary background explanations and making needed distinctions along the way. The easiest (but not the most exciting) way to read a Summa Article is to read this part first.

Fifth and finally, each Objection must be addressed and answered—not merely by repeating an argument to prove the opposite conclusion, for that has already been done in the body of the Article, but by explaining where and how the Objection went wrong, i.e., by distinguishing the truth from the falsity in the Objection.

No one of these five steps can be omitted if we want to have good grounds for settling a controverted question. If our question is vaguely or confusedly formulated, our answer will be, too. If we do not consider opposing views, we spar without a partner and paw the air.

If we do not do our homework, we only skim the shallows of our selves. If we do not prove our thesis, we are dogmatic, not critical. And if we do not understand and refute our opponents, we are left with the nagging uncertainty that we have missed something and not really ended the contest.

Like Socratic dialogue for Plato, this medieval method of philosophizing was very fruitful in its own day—and then subsequently neglected, especially in our day. That is one of the unsolved mysteries of Western thought. Surely both the Socratic and the Thomistic methodological trees can still bear much good fruit. Perhaps what stands in the way is our craze for originality and our proud refusal to be anyone’s apprentice. I for one would be very happy to be Aquinas’s apprentice, or Socrates. CH

By Peter Kreeft

[Christian History originally published this article in Christian History Issue #73 in 2002]

Peter Kreeft teaches philosophy at Boston College. This article was taken from his book Summa of the Summa (Ignatius Press, 1990).
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