How to Think Like Aquinas

by Kevin Vost

  Questions 1–21 in the First Part of the Second Part of the Summa Theologica address such issues of human acts, taking more than a hundred pages to do so. Here, we’ll give you the highlights.

  Voluntas — the will — is a uniquely human power. It’s such an important subject in understanding our freedom and our salvation that St. Thomas uses the word in ways that are more exacting than our colloquial understanding of will as “whatever I happen to want at the moment.” As the intellect seeks to know the true, the will seeks to obtain the good. The intellect operates in the realm of knowledge, and the will in the realm of love. The intellect discerns what is good, and the will acts to get it. The will is the capacity to desire what is truly good. Hold on! In the everyday sense, we know that we can desire the truly good — but we don’t always pursue it. But first things first: without a will, we couldn’t even desire it.

  Since the ultimate goal, or end, of man is the attainment of happiness, there is a sense in which the will itself is not free, since no one can truly desire unhappiness. Augustine says, “All desire happiness with one will,” and Thomas agrees, saying, “The will desires something of necessity.”94 This does not mean, as some modern deterministic psychologists and philosophers hold, that we have no free will, that our acts are determined for us and are not our responsibility. Indeed, Thomas retorts to deniers of free will, “I answer that, Man has free will: otherwise counsels, exhortations, commands, prohibitions, rewards, and punishments would be in vain.”95

  If the will is necessitated to desire the good, how, then, can we have free will? Thomas says that the “proper act” of free will is choice. We have freedom of exercise to choose whether to employ our wills and make a choice one way or another in a given situation. (Surely procrastinators can relate to this!) We have freedom of specification to select one thing or course of action while rejecting others. Our free choice is not in regard to the ultimate end or goal: we want happiness. What we choose is the means to that end. It is through our ability to choose or not to choose between different means that we exercise free will and become active, nondetermined agents — masters of our own actions and worthy of praise or of blame.

  On Verification

  If Brother John (or you and I) truly want to grow in knowledge, we will strive to arrive at the meaning of whatever material we read. To read a book requires so much more than sounding out phonetically the words on the printed page. We must not be like parrots repeating the author’s words without knowing what they mean. We need to read carefully to understand what an author means. For unfamiliar words, we may need to consult a dictionary or a learned friend.

  Further, once we have grasped96 the gist of the author’s statements, we need to ask ourselves, “Is it true?” There is an old saying that “you can’t believe everything you read in the newspapers,” and an updated version that “you can’t believe everything you read on the Internet.”

  As Catholics, we believe in one special infallible book (collection of books, more precisely): the Bible, of course, as understood and interpreted authoritatively by the Church. We do not doubt the Bible’s contents, but even so, we are not merely a “people of the book.” Christ did not write a book; He founded a Church, which later provided us with the books inspired by God. Further, an old saying goes, “I fear the man of one book,” and, interestingly, it is often attributed to none other than St. Thomas Aquinas!97 In other words, we should fear those who are overspecialized, whose views may be excessively narrow, failing to understand any subject completely by being blind to how it relates to the web of other truths that put it into full context. As for our precept here, if we read something doubtful, one method to verify its truth is to consult other reliable sources, perhaps with other conclusions, and then to submit the issue to our own reasoning powers. We can also acquaint ourselves with common logical fallacies and erroneous ideological assumptions that can lead arguments astray.98 In terms of factual matters, this can sometimes be done by controlled observations or experiments, the stuff of the scientific method. Thomas was well aware of it in his day. His great mentor, after all, St. Albert the Great, is the patron saint of scientists! In terms of theological matters, we turn to the teaching Magisterium of the Catholic Church.99

  Doctor’s Orders ✍

  Prescription for Unlocking Understanding

  Reflect

  We covered a lot of ground in this chapter, and hopefully it has provided us with a firm foundation for a better understanding of ourselves and, therefore, of everything else! Here is a little thinking exercise for you. Thomas, in his writings on the virtue of prudence, spoke of a “twofold” power of understanding, both the power to grasp universal ethical principles (such as “do the good”) and the power to understand the nature of particular things or choices we face to determine whether they truly embody “the good” in a particular situation. These can be seen as the universal and singular premises of an ethical syllogism, to put it abstractly, something like this:

  I should do the good (universal premise).

  This particular course of action is (or is not) good (singular premise).

  Therefore, I should (or should not) pursue it (conclusion).

  Think of a challenging practical situation you recently faced, something that required you to choose between actions to achieve your goal in your academic, work-related, or personal life. Can you look back on your “twofold” powers of understanding in action by ferreting out the kinds of universal and singular premises you used to arrive at your decision about what to do?100 You might even consider writing them down. Next, do you face some kind of decision right now, or will you in the near future, that will require a prudent decision on your part? If so, what kind of universal and singular premises apply to that situation, and how might you use your powers of memory and understanding to make the most prudent decision?

  Read

  Thomas’s analysis of understanding as a part of prudence is in his Summa Theologica.101 His explanation of the nature of man and the powers of the soul can be found in his Commentary on Aristotle’s De Anima (On the Soul) and in the Treatise of Man.102 The most clear and helpful book I have found on these issues is in Robert Brennan, O.P., Ph.D.’s Thomistic Psychology: A Philosophic Analysis of the Nature of Man. Another good and easy read on the subject is Mortimer J. Adler’s Intellect: Mind Over Matter.103 Finally, a more challenging but worthwhile book, hot off the presses in 2017, is Dr. Peter Redpath’s aforementioned Moral Psychology of St. Thomas Aquinas: An Introduction to Ragamuffin Ethics.

  Remember

  Never forgetting that rehearsal is the mother of memory, let’s start by reviewing our memory foyer again. Do you recall all ten locations and images and the precepts that they contain? If not, it’s time for a little more rehearsal. Another repetition or two should help lock them all in and warm us up for the heavy-duty memory work we’ll do in part 2.

  78Summa Theologica, I, Q. 72, art. 1.

  79Peter Redpath, The Moral Psychology of St. Thomas Aquinas: An Introduction to Ragamuffin Ethics (St. Louis: En Route Books, 2017), 32.

  80St. Thomas Aquinas, Commentary on Aristotle’s De Anima (Notre Dame, IN: Dumb Ox Books, 1994), 1.

  81On the Soul, bk. 2, chap. 12; cited in The Complete Works of Aristotle: The Revised Oxford Translation, ed. Jonathan Barnes (Princeton, NJ: Princeton University Press, 1984), 657.

  82Aquinas’s Commentary on De Anima (On the Soul), bk. 2, chap. 1, cited in Aquinas on Human Nature, ed. Thomas S. Hibbs (Indianapolis, IN: Hackett, 1999), 19.

  83This is the official teaching of the Church as well. See CCC 365.

  84You may have seen a variant of this scenario in my books The One-Minute Aquinas: The Doctor’s Quick Answers to Fundamental Questions (Sophia Institute Press, 2014) and Unearthing Your Ten Talents: A Thomistic Guide to Spiritual Growth through the Virtues and the Gifts (Sophia Institute
Press, 2009). If you already know the answer, please don’t spoil it for new readers!

  85“Phantasms” in Aristotle’s Greek, deriving from the word phos, meaning “light.”

  86On the Soul, bk.3, chap. 7.

  87My wife was just reading over my shoulder while proofing this, and she does not dispute it! (And, strange as it seems to me, she does not hesitate to handle snakes when offered the chance at the zoo, to which offers I say, “No, thank you.”)

  88Strictly speaking, Thomas does not say we have two intellects, but two primary powers of the intellect used in concept formation. This intellectual power may also be referred to as the passive or potential intellect. In Thomas’s Latin it is intellectus possibilis.

  89It is a very crucial one, and we’ll encounter some of its misunderstandings in chapter 12. Many modern philosophers and psychologists since the days of John Locke in the seventeenth century have cast doubt on the powers of the mind by supposing that ideas are the objects of our thinking, or that which we think about, thus severing the direct connection between our ideas and the outside world. St. Thomas makes clear that things themselves are the objects of our ideas and our ideas are primarily a means, or that by which we think about things, although we also possess the self-reflective capacity to think about our thinking, when we are so inclined.

  90Adapted from, Robert E. Brennan, Thomistic Psychology (New York: MacMillan, 1941), 183.

  91Since humans are soul-body composites, the soul is indeed supplied with phantasms by bodily organs, such as the sense organs, which send information to our brains. Thus, damage to those material organs can hinder the spiritual intellect from forming new ideas and performing other intellectual operations, such as judgment and reasoning.

  92Summa Theologica, I, Q. 75, art. 5.

  93Readers intrigued by angels will delight in the Angelic Doctor’s treatise about them, including their unique thinking capacities. Summa Theologica, Qs. 50–64.

  94Summa Theologica, I, Q. 82, art. 1.

  95Ibid., I, Q. 83, art. 1. For an interesting look at the claims of some neuroscientists and social psychologists who claim on the basis of very simple and flawed experiments that they have disproved the existence of free will, I recommend Alfred R. Mele, Free: Why Science Hasn’t Disproved Free Will (New York: Oxford University Press, 2014).

  96If I might digress a bit, our word “comprehend” derives from the Latin prehendere, “to take hold of, or grasp.” Indeed, most of our common English words for the abstract thinking operations of the intellect reveal their foundations in the sensations and motions of the physical body and the sensitive powers of the soul, just as Thomas taught. “Consider” is from sidera, “to gaze at” the stars; “reflect” is from reflectere, “to bend back”; “discern” is from circus, to mark off with “a circle or ringed area”; and “cogitate” is from agitare, “to shake up or turn over.” Fr. Brennan provides these and five more examples in Robert Edward Brennan, Thomistic Psychology: A Philosophic Analysis of the Nature of Man (New York: Macmillan, 1941).

  97I have not been able to pinpoint this in his writings myself. A quick Internet search yields Thomist Dr. Taylor Marshall’s thoughts on the matter (though he could not find it either!). Dr. Taylor Marshall, “Did Thomas Aquinas Fear the Man of One Book?” Taylor Marshall, Ph.D. (blog), August 10, 2015, http://taylormarshall.com/2015/08/did-thomas-aquinas-fear-the-man-of-one-book.html.

  98This is the stuff of chapters 11 and 12.

  99The stuff of chapter 13.

  100Both kinds of premises could vary widely depending on your circumstances. Universal premises, for instance, might involve the value of pursuing higher education while balancing family obligations, and the singular premise might involve particular programs at particular schools.

  101Summa Theologica, II-II, Q. 49, art. 2.

  102Ibid., I, Qs. 75–89.

  103Mortimer Jerome Adler, Intellect: Mind over Matter (New York: Macmillan, 1990).

  Chapter 9

  Filling Your Mental Cupboard to the Brim: On Building a Knowledge Base

  Put whatever you learn into the cupboard of your mind as if you were filling a cup to the brim.

  Fill’er Up, Please — with Knowledge

  Again, we see a nod to the power and importance of memory. In his opening statement to Brother John, Thomas recommended acquiring a thesauro scientiae, a storehouse or hoard of treasures of knowledge. Here our metaphor moves to the mind as a storehouse of intellectual food and as a cup to be filled with the fine wine of knowledge. What is worth learning is worth remembering, and a trained memory will supply us with a place for everything and will supply everything with a place. Indeed, Thomas was well aware that, centuries before him, St. Jerome, commenting on the passage in which Ezekiel was told by God, “eat this scroll” (Ezek. 3:1), wrote:

  Eating the book is the starting-point of reading and of basic history. When, by diligent meditation, we store away the book of the Lord in our memorial treasury, our belly is filled spiritually and our guts are satisfied. . . . Nothing that you have seen or heard is useful, however, unless you deposit what you should see and hear in the treasury of your memory.104

  Note, too, Thomas’s admonition to fill our cups to the brim. We should be so thirsty for truth that no half-filled cup will do! Bl. Humbert of Romans, who served as Dominican master general during Thomas’s adulthood, borrowing from St. Bernard of Clairvaux, wrote that preachers should not be like a pipe that receives and pours all at once, but like a bowl that fills up and then overflows, sharing its contents with others. We, too, should emulate the good preacher, by striving always to fill our cups of knowledge. Truly, no one can learn everything, but God has crafted our finite intellects with such vast storage capacities that we can truly strive for the rest of our lives to fill our mental storehouse with truths and never need worry about running out of room. An old Jewish saying holds that even a bushel filled to the brim with nuts can hold further measures of oil.

  The Power of a Broad, Sturdy Knowledge Base

  Modern psychologists would call the process of filling mental cupboards to the brim building a broad knowledge base. You’ve heard the old saying that “the rich get richer, and the poor get poorer.”105 There is a sense in which this principle operates in our capacities to learn and think. We learn new things by making connections with things we already know, like the narrow streams that eventually lead to broad seas in Thomas’s metaphor. The more things you know, the easier it is to make new connections and to learn even more. The accumulation of what one learns over time is one’s knowledge base. Thomas’s knowledge base was like a mountain base — and the whole mountain on top of it! Any of us who try, though, can build our own knowledge base, especially if we employ memory and study methods like the ones we encountered in chapter 7.

  A broad knowledge base even has practical advantages in helping us “think on our feet” and make hard real-world decisions. Once we have built a firm base of knowledge and experience, we will be better prepared to make quick decisions and act quickly when faced with the unexpected. We will have more resources to draw on. The broader and sturdier we’ve built our knowledge base, the more likely those swift decisions will be sound ones.

  An interesting study on the power of a knowledge base was reported in the 1970s.106 A group of ten-year-olds was pitted against a group of adults on two kinds of memory tasks, one a test of ability to recall random ten-digit numbers, and the second involving memorization of the positions of chess pieces. When it came to digit recall, adults won, as was expected. (The average recall for adults is about seven digits in order; for ten-year-olds, it is about six.) Still, the children recalled the chess-piece positions better than the adults because they, and not the adults, were regular chess players. In other words, though their raw memo
ry capacities were not yet as strong as those of the adults, the power of the children’s knowledge base of the game of chess allowed them to outperform the grown-ups in that chess-related task.107

  Our lesson here is that a sizable knowledge base of both important ethical principles and factual information about the kinds of tasks and situations in which we are placed will make it far easier for us to make quick, wise decisions when faced with the unexpected. If we are to think well on our feet, our feet need to be planted on a firm, substantial knowledge base.108

  Further, there is good news at the opposite end of the life span as well, for although various mental capacities (such as those for retaining new learning, mental quickness at recall and calculations, and so forth) may show some decline, one’s knowledge base, as measured by things such as retention of long-known facts and vocabulary, tend to remain very robust even in healthy individuals who are very elderly.