Why You Should Start Thinking Like Thomas Aquinas

The human soul is the highest and noblest of forms. Wherefore it excels corporeal matter in its power by the fact that it has an operation and a power in which corporeal matter has no share whatsoever. This power is called the intellect.

— St. Thomas Aquinas, Summa Theologica, I, Q. 76, art. 2

Why Should You Think Like Aquinas?

We should all strive to think more like Aquinas, but only if we desire to know what is true, to love what is good, to grow in happiness and holiness while wayfarers on earth, and ultimately to share in eternal beatitude with God and the communion of saints when we arrive home in heaven. You see, in all of human history, St. Thomas Aquinas (1225–1274) was among the very best guides to fulfilling these desires.

Dozens of popes have sung his praises as philosopher and theologian, the Catechism of the Catholic Church abounds in references to his writings, and even secular scholars have acknowledged his monumental contribution to the field of philosophy. They praise him foremost for what G. K. Chesterton called in his biography of Thomas “that unusual human hobby: the habit of thinking.”

Of course, by thinking like Aquinas I do not pretend to possess the keys to thinking as well as St. Thomas (as much as I wish I did!). Thomas was gifted with a uniquely powerful intellect and was quite aware that God gives some of us more powerful potential for greater depths of thinking than He gives others: “Experience shows that some understand more profoundly than do others; as one who carries a conclusion to its first principles and ultimate causes understands it better than one who reduces it to its proximate causes.”

Many centuries later, groups of modern psychologists have concluded repeatedly that the capacity for higher-level “abstract thinking” (the stuff of “first principles and ultimate causes”) is a fundamental hallmark of human intelligence. So, Thomas truly understood the nature of thinking and the habits required to perfect it. He was blessed with a uniquely powerful intelligence able to fathom the most ultimate of causes and principles. Further, he possessed the capacity to enlighten others by making the abstract more concrete, by capturing lofty truths and bringing them down to earth, so that the average person could grab onto them firmly and be raised up by them.

Regardless of how you might think of yourself as a thinker, Thomas is a most trustworthy guide for helping you to maximize your unique God-given capacities to think and reason about the things that matter most to you. Further, whoever has the capacity to read and understand these pages has the capacity to improve greatly his powers of thinking — indeed, to grow adept at that most “unusual hobby” and think more like Aquinas!

Perhaps more than ever, we need to develop our capacities for clear thought on the things that always matter the most, such as the existence and the nature of God and how we should live our lives and relate to our Church, families, neighbors, and fellow citizens.

We live in a day when many young people declare themselves “nones” (people with no religious affiliation) amidst a barrage of propaganda that people who value thinking should choose reason and science over faith and religion, with the latter presented as matters of blind belief, sentimental tradition, and remnants of primitive superstition.

In our time, St. John Paul II stated elegantly how faith and reason, properly understood, are not at all opposed, but “are like two wings on which the human spirit rises to the contemplation of truth.” Nearly eight centuries ago, St. Thomas Aquinas, the “Angelic Doctor,” showed us many ways to obtain maximum lift from both of those wings, and that is what this book is about.

This article is a preview of How to Think Like Aquinas.

As for what we might call the “wing of reason,” Thomas knew well that the powers of thought that arise from our human nature are “also aided by art and diligence.” In other words, intelligent thought and accurate thinking are not just capacities that you and I have in some fixed measure but are flexible potentials that can be built, improved, and actualized by training and practice (“diligence”) in the right methods (“art” being short for “artificial” or man-made). Your powers of memory, for example, or of logical reasoning, are fluid capacities that you can build and improve by using them in the right ways. As we proceed through this book we will learn the ways provided in the writings of St. Thomas — and practice them as we go!

As for the “wing of faith,” Thomas knew as well that “grace does not destroy nature but perfects it; natural reason should minister to faith as the natural bent of the will ministers to charity.” Further, “when a man’s will is ready to believe, he loves the truth he believes; he thinks out and takes to heart whatever reasons he can find in support thereof; and in this way human reason does not exclude the merit of faith but is a sign of greater merit.”

Clearly then, Thomas knew that God gave us reason for a reason — to find truth in the world around us and to serve the faith that will guide us to Truth in eternity. It is up to us, then, to build on our natural thinking capacities both by developing and practicing the arts that perfect them on a natural plane, and by becoming more open to the graces from above that will raise them to heavenly heights.

How Can You Think Like Aquinas?

We can all come to think more like Aquinas in three steps:

  1. By reading and reflecting on what he wrote specifically about thinking, study, and the nature of perfection of the human intellect
  2. By observing the methods of thinking St. Thomas employed in his great writings, such as his over-three-million-word Summa Theologica and many others
  3. By practicing what he preached and taught through simple exercises.

As for the first step, our guiding template will be the brief, elegant, delightful “Letter of St. Thomas to Brother John on How to Study.”

On Sailing Your Way toward a Treasure Trove of Knowledge

This letter’s authenticity, as having been penned by St. Thomas, has been questioned by some. We don’t know, for example, who this Brother John was or when the letter was written. Still, Thomas was known to take time from his prodigious writing, teaching, and preaching duties to respond to letters requesting his advice.

Further, commentators, including Father White and Father Sertillanges, note that its content is quite consistent with statements found in Thomas’s other writings. This letter’s worth, then, is unquestionable for those who would strive to think like Aquinas! Let’s dive in now and reflect on it. Here is its introduction:

Because you have asked me, Brother John, most dear to me in Christ, how to set about acquiring the treasure of knowledge, this is my advice to you; namely, that you should choose to enter by small rivers, and not go straight into the sea; for difficult things should be reached by way of easy things. Such is therefore my advice on your way of life.

The first lesson to be gleaned is that to think like Aquinas is to center one’s thoughts and affections on Jesus Christ. A second lesson is that knowledge is indeed a rightful treasure to be sought by the followers of Christ. Christ declared that what we treasure reveals our heart’s desires and we should seek not earthly, but heavenly treasures (see Matt. 6:19–21). Clearly, then, to seek truth is a proper desire and one that will be fulfilled completely with the Beatific Vision of God, who is Truth. In the meanwhile, here on earth, to obtain truth requires both the sweat of our brows and application of the right methods.

Thomas reveals that the first of those methods is to approach the vast sea of knowledge via smaller, more navigable streams. We learn new things by comparing and contrasting them with things we already know, thereby widening the channels of our knowledge, bit by bit. We see this, for example, in the way we first learn the names of numbers and how to count before we move to addition, subtraction, multiplication, and division, and onto higher mathematical functions such as algebra, geometry, and such.

Who could possibly survive the deep seas of calculus without having reached it via those ever-widening streams? Further, we navigate these streams and reach broader, deeper channels by following the guidance of our teachers, who have traveled much farther upstream than we have.

That is all common sense, but Voltaire said that “common sense is not so common,” and ironically, we often see the lack of it in many of his modern heirs who criticize Christ and His Church. By this I refer to some modern atheists who navigate their way up the rivers of knowledge in their own specialty areas, such as mathematics or biology, but then dive right into the oceans of philosophy and theology with no conception of how far they are out of their depth!

For now, let us note that Thomas’s advice in his letter concerns not merely study, but a “way of life.”

Editor’s note: This article is a preview of Dr. Vost’s How to Think Like Aquinas: The Sure Way to Perfect Your Mental Powerswhich is scheduled to be released on Sept. 20, 2018 from Sophia Institute Press.

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Dr. Kevin Vost, Psy D. is the author of Memorize the Faith, The Seven Deadly Sins, The One Minute Aquinasas well as numerous other books and articles. He has taught psychology at the University of Illinois at Springfield, Lincoln Land Community College, and MacMurray College. He is a Research Review Committee Member for American Mensa, which promotes the scientific study of human intelligence. You can find him at drvost.com.

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