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  • Writer's pictureAaron Mead

Aquinas on the Virtues: Understanding

Today I begin a series of posts on Thomas Aquinas’s view of the virtues. Most of my focus in this series will be on what are often called the “cardinal” virtues—wisdom (or “prudence”), justice, courage, and temperance—and the “theological” virtues—faith, hope, and love (or “charity”). However, in order for that discussion to make sense, I need to begin with the virtue of understanding.

Understanding is what Aquinas calls an “intellectual” virtue, i.e., an excellent quality of the thinking part of our minds that allows us to think or reason well in a particular sense. As Aquinas puts it, understanding allows us to grasp “self-evident principles both in speculative and in practical matters” (Summa Theologica I-II, Question 58, Article 4). This dense statement needs some unpacking.

Aquinas distinguishes, here, between “speculative” matters and “practical” matters. Practical matters are matters related to what we should do. For example, since I want to keep my job, I should show up to work every day on time. This is a principle governing what I should do, and so it is a practical principle—a principle about a certain practical matter.

In contrast, speculative matters are matters related to the way things are. Consider the following version of a famous argument:

  1. Socrates is a human.

  2. All humans are mortal.

  3. Therefore, Socrates is mortal.

This argument makes use of a principle in line 2: “All humans are mortal.” But, this is not a principle about what any of us should do. Rather, it is a general claim about the way things are: human beings are mortal, i.e., we all die. So, it is a speculative principle. The most obvious examples of speculative principles are principles of science, such as Newton’s law of gravity or the laws of electromagnetism.

Now, in Aquinas’s statement above, he says that understanding is the virtue that helps us grasp “self-evident” practical and speculative principles. What does that mean? To say that a principle is “self-evident” is to say that we don’t need any proof to know that it is true. From this definition, we can see pretty quickly that Aquinas would not think Newton’s law of gravity or the laws of electromagnetism are self-evident. Indeed, those require proof by way of experiments and complicated mathematical reasoning.

What then does Aquinas have in mind? Some examples will help. Aquinas thinks the virtue of understanding helps us grasp the following self-evident practical principle: “Good is to be done and pursued, and evil is to be avoided” (Summa Theologica I-II, Question 94, Article 2). In other words, do good and don’t do bad. If, after reading that principle, you said to yourself, “Duh!”, then you have the virtue of understanding (whew!). Aquinas thinks this is the first principle of all practical reasoning—all other practical principles derive from it or depend upon it in some way—and he thinks it is self-evident: its truth is clear without any sort of proof. (He also refers to it as the first principle of the “natural law”.)

Now, if you’re a philosophical type, you’re probably thinking, “That principle isn’t very useful since it still leaves open the question of what counts as good and bad.” The real work of figuring out what to do is in determining which actions are good and which are bad. Thankfully, Aquinas says there are further self-evident practical principles that we can grasp with our understanding, and these further principles fill out the picture of what is good more concretely.

For example, Aquinas thinks it is self-evident that life is a good to be pursued by human beings (Summa Theologica I-II, Question 94, Article 2). We are living creatures, and so life is a basic good for us. Consequently, death is a fundamental evil for us, insofar as it is a destruction of life. From these basic ideas we can see pretty clearly how we would end up with a moral rule against murder and why we would generally view saving life as a noble thing.

Similarly, Aquinas thinks knowledge and social relationships are basic human goods (perhaps among still others) that we grasp by way of the virtue of understanding. He thinks we are, fundamentally, reasoning creatures and social creatures, and so knowledge and relationships are goods for us. We can imagine how moral norms against lying and betrayal, and in favor of truth-telling and loyalty, might derive from these two goods.

Now, to say that principles like, “avoid the destruction of life,” “pursue knowledge,” or “pursue friendship” are self-evident might be controversial; they seem less obvious than the principle, “do good and avoid evil.” After all, we can imagine someone disagreeing that life, knowledge, and social relationships are fundamental human goods. So, are they really self-evident?

To this sort of objection, Aquinas would likely reply that to say a principle is “self-evident” is not to say that everyone will find it to be obviously true. Rather, it is to say that given the right kind of experience and the ability to reason well, a person will see that such principles are true without requiring proof. In short, if one has the virtue of understanding the principles will be obvious.

Finally, it’s worth noting that even if we grant Aquinas’s framework so far, this still leaves a lot of room to disagree over what we ought to do. For example, while most people would likely agree that life is a good that humans should go for, people still have entrenched disagreements over whether and under what circumstances it might be appropriate to kill someone (e.g., abortion, capital punishment, war, etc.).

So, while Aquinas thinks some basic practical matters are obvious to those with the virtue of understanding, he does not think the virtue of understanding gets us the answers to every practical question we might have. Just as Newton’s law of gravity is not a self-evident speculative principle, practical principles about very concrete moral questions are generally not self-evident.

In the next installment of this series, I’ll examine Aquinas’s view of the cardinal virtue of wisdom—another intellectual virtue with a function different from understanding. Stay tuned!

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