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The Problems Thomists Don’t Have

written by Dr. Brian Huffling

An intro course or book about philosophy will quickly reveal that much of philosophy is an attempt to solve problems and answer questions. To an extent this is the sine qua non of philosophy. However, some of these “problems” are simply pseudo-problems that arise because of a rejection of a proper metaphysics. In this article I argue that the Aristotelian/Thomistic (AT) metaphysical/epistemological system avoids many of the usual problems that philosophers try to solve. I say “Aristotelian/Thomistic since Thomas Aquinas relied heavily on the thinking of Aristotle. (I should further add that the type of Thomism I have in mind is existential Thomism in the vein of Etienne Gilson and John Owens. See some of their works here under “Philosophy Books”.) Some such problems are the mind/body problem, the problem of skepticism, the problem of agnosticism, and the Gettier problem. 

Alleged Philosophical Problems

The Mind-Body Problem

The mind-body problem is “how does an immaterial soul interact with a material body?” This is a problem if the soul and body are both separate substances in their own right. While René Descartes is not the only philosopher to maintain that the spirit/mind and body are separate substances, the mind-body problem really arose out of Descartes’ system of thought. I have written another article on this topic, but in short, Descartes taught that in order to have certainty we have to start with a method that cannot allow doubt. The senses can be fooled, according to Descartes, so we have to start on our quest of certainty without the use of the senses. He starts with the fact that he is thinking, which he can’t doubt, because he would be thinking that he was doubting. He therefore thinks, and if he thinks, then he exists. He thus begins his quest for certainty with “I think therefore I am.” Everything else is deduced from that. God is deduced since Descartes has a sense of perfection, which he argues can only come from a perfect being. Also, since God is perfect and since existence is a perfection, God must exist. If God exists as a perfect being, then he wouldn’t allow Descartes to believe in the materiality of his body and the world if they didn’t truly exist. Thus, his belief in matter is justified.

With this dualism between the mind and body we have the so-called mind-body problem. That is, how does the mind as an immaterial substance interact with the body, which is a material substance? His answer was that the mind interacts with the body through a gland in the brain called the pineal gland. The problem with his response is that the pineal glad is also material, so it doesn’t really answer the question. Philosophers who hold to substance dualism have been trying to answer this problem with no ubiquitous satisfaction.

It is important to note that Descartes was a rationalist. That is, for him knowledge started with the mind and works its way out to the world. With some, the world is simply in the mind, but that’s another topic.

The Problem of Skepticism

David Hume made popular the problem of induction, which led to skepticism. He argued that all of our knowledge comes from the senses. Thus, as opposed to Descartes, he is an empiricist. The physical world made “impressions” on the mind via the senses. These impressions cause ideas in our minds. These are the two ways of knowing: impressions and ideas. We have impressions of birds, trees, and stars. But we do not have sensations of causality, the self, God, beauty, ethics, and these kinds of things. Since there is no impression of causality, we cannot know there is such a thing. Hume never rejected it as such; in fact in a letter he said that he had never rejected it. However, he did say that we have no rational justification for cause and effect since we have no direct impressions of it. Thus, we cannot say for certain that one thing causes another. The famous example is one billiard ball hitting another. One ball strikes another and it moves. We can’t say the first ball made the second ball move; we just have always put the two events together and made a habit or custom of saying that one ball caused the other to move. Thus, ‘causality’ for Hume is just a habit of constant conjoining of two events taken together where one usually follows the other.

Since for Hume induction (knowing something through experience) is based on the notion of cause and effect, there is a problem. We think the future is going to be like the past, but there is no real justification for it, says Hume. Since things don’t have natures, like human natures (there is no impression of them), and there is no cause and effect relationship, we cannot with rational justification say “in the presence of X we always will have the presence of Y.” In fact, he is famous for saying that we cannot even be justified in saying the sun will rise tomorrow since we can’t know the future is like the past. This problem of not knowing how things will behave is called the problem of induction. If something happens ninety-nine times in a row, such as seeing a ball break through a window (something I caused many times as a kid), we can’t say with justification that the same will happen the hundredth time.

With these notions in play, Hume is left an extreme skeptic. We have no rational justification for God, morality, miracles, knowledge of many things about the world, or ethics. He even says we have no rational justification for the identity through time of the self! Again, he doesn’t deny we have a continuous self, just that we can’t justify our knowledge of it since we don’t have impressions of it. Many have their skepticism fueled by the thinking of David Hume.

The Problem of Agnosticism

If Hume is right regarding induction, then science is impossible since it relies on things behaving in regular ways. However, if we cannot know if there are causes and what effects they bring about, then science is over. This level of skepticism scared Immanuel Kant. Given Humean skepticism, Newtonian physics was in jeopardy, and Kant did not want that to be the case. He wanted to “save the appearances” of Newtonian physics and our views of the world. Kant wanted to defeat Hume’s skepticism to save science.

Kant wanted to show how we could have universal knowledge that relates to the world. He thought we could easily show one can have universal knowledge, but this knowledge didn’t seem to relate to the world. Such knowledge is ‘analytic’, meaning that the predicate is contained in the subject. An example is “The mother is a woman.” The notion of “woman” is inherent in “mother,” and thus does not provide new knowledge. Such knowledge is true by definition and is universal. It is universal because it is ‘a priori’ or known apart from experience because it is simply true by definition (according to Kant).

However, he did not think that we could have universal knowledge from the senses because they only give us contingent knowledge about the world. Such knowledge that is based on experience is called ‘a posteriori’ knowledge. While a priori knowledge gives us universal and necessary knowledge, a posteriori knowledge only gives contingent knowledge. However, we seem to have knowledge from the world that is universal and necessary. Such knowledge is a posteriori in that it is based on experience. It is also synthetic since it is not analytic. Synthetic statements add something new to the subject. Kant’s question was, “How do we have synthetic a priori knowledge?” That is, how do we have knowledge based on experience that is universal?” If a priori knowledge is universal but doesn’t come from experience, then what good is it? However, if a posteriori knowledge is from experience but it’s not universal and necessary, what good is it? So, Kant wanted to know if/how we can have universal and necessary knowledge that relates to our everyday lives and experience.

Kant’s answer is odd and confusing (as if the above isn’t confusing enough). He imported aspects of rationalism and empiricism into his epistemology. The a priori aspects (those that are universal and necessary) are supplied by the mind, or understanding. The a posteriori aspects are supplied by the senses. The intellect and senses have a dual role in knowledge in that the sensible world presents itself to the person and the intellect takes the data from the senses and categorizes them. There are twelve different categories the mind uses to categorize the data (they are grouped into quality, quantity, relation, and modality, that is possibility/necessity).

The problem is, we can’t know reality apart from the mind categorizing it. We only know the world after it has been categorized. The uncategorized world Kant called the nounema (or the noumenal realm). The categorized data is called the phenomena (or the phenomenal realm). The phenomena is what we have “knowledge” of and what science is about. The obvious question is, “How do we know how the world really is?” Answer: we don’t. We are left in agnosticism as to what reality (the noumena) is. Thus, Kant solved Hume’s skepticism with agnosticism. He saved the appearances, but that’s all they are: appearances.

The Gettier Problem

A more recent problem has been how to define knowledge. One standard way of doing so was to say that one has knowledge if he is justified in believing something, he did in fact believe it, and if it were true. This view of knowledge is called the tripartite view of knowledge since it has three parts: justified true belief (or JTB). If one had JTB, then one had knowledge. For example, if one saw a bird in the back yard he would have knowledge of this bird if he had justification for believing he saw it, he did believe it, and it were true that there was a bird in the back yard.

In 1963, a professor named Edmund Gettier wrote an article about two pages long that completely changed the contemporary field of epistemology. He argued that, contra many in the field, one could have JTB and still not have knowledge. One type of counterexample for the JTB theory, given by Gettier is this. Two men, Jones and Smith, are applying for a job. Smith has evidence that Jones will get the job and Jones has ten coins in his pocket. He thus forms the proposition, “The man with ten coins in his pocket will get the job.” For whatever reason, Smith, not Jones, gets the job. Unbeknownst to Smith, he also has ten coins in his pocket. According to Gettier, Smith had justification for the proposition “The man with ten coins in his pocket will get the job,” he believed it, and it was true. However, Smith could not be said to know it, since it was accidental. Thus, Gettier demonstrated that the JTB theory of knowledge doesn’t work. Hence the “Gettier Problem.” In fact the problem of how we account for knowledge has been so severe in epistemology that many philosophers don’t even bother talking about knowledge and only talk about how we are justified in what we believe.

Thomistic Responses

A full-blown explanation of Aristotelian/Thomistic metaphysics/epistemology is too much for this article. I will offer a very brief sketch that in my opinion shows that it does not suffer from the above problems.

Response to the Mind-Body Problem

Since I have an article on this very issue I am only going to offer a sketch here as to the response to the mind-body problem. The problem assumes substance dualism—that the soul/mind and body are each complete substances in themselves. The Aristotelian/Thomistic position says that the soul/body are not complete substances as taken separately. They are each aspects of one substance. This view is called ‘hylomorphism’. The soul is the form that “informs” the body and makes the being what it is. For example, the man is a substance as an individual. The soul/mind is incomplete, as is the body. Taken together they form one substance. Thus, there is no problem as to how they relate to each other since the soul and body form one substance. They work together as a unity. See the response to the Gettier problem for more on this.

Response to Hume’s Skepticism

The problem of induction makes the assumption of nominalism. ‘Nominalism’ is the view that things don’t have natures. On the other hand ‘realism’ says that things do have natures. For example, realists say that humans share a human nature or essence. We have something in common with each other that makes us human. We all share in ‘humanity’. Nominalists on the other hand say we share certain characteristics with each other, but we don’t have some nature in common. We resemble each other, have things in common, or are simply in the same class as each other. However, humans don’t have an essence that makes us humans.

If we deny that things have natures, then they might not all have certain attributes, behaviors, etc. If ninety-nine rocks are thrown through windows, we can’t say for sure that the window will break the next time. However, this is ridiculous. Windows break when a rock is thrown at them (depending on the thickness of the glass, etc.). This is because of the nature of rocks and the nature of windows. If realism is true and things have essences (e.g. a horse essence, or a tree essence, and so on), then we can make universal statements about those things. This is the only way science is possible. We can’t talk about human brains if there is no nature to human brains. Science and medicine are possible because we know about the natures of humans and their brains, and how certain medicines affect them. Thus, realism solves the problem of induction and the cause/effect problem, and skepticism.

Response to Kant’s Agnosticism

The answer to Kant’s agnosticism lies in the answers already given, namely, the Thomistic account of knowledge and realism regarding natures. Since the Aristotelian/Thomist maintains that we know reality directly, there is no “Kantian gulf” to cross. Descartes and Kant introduced such a gulf, now called critical realism; however, a direct realist has no such gulf.

Further, we maintain that all knowledge begins in the senses. We are not born with a priori ideas/categories (something Kant cannot prove). Like Kant, we assert that the senses and intellect work together for knowledge. But the senses and intellect know the thing in itself. There are no a priori categories hiding the real world. The sensible objects impose themselves on the passive intellect. The active part of the intellect strips away (abstracts) the immaterial aspect of things (the form), letting us know them universally. The objects actually exist in our minds (immaterially in their form as abstracted) and are thus known by our minds. Such a realist epistemology avoids both skepticism and agnosticism.

Response to the Gettier Problem

When teaching, I’m often asked, “How do Thomists respond to the Gettier problem?” My answer is, “We don’t have a Gettier problem!” We tend to agree with Gettier in showing that JTB fails to account for knowledge. But we don’t define knowledge that way. Aristotelians/Thomists define knowledge as a union between the knower and the thing known. This is possible because of hylomorphism. As mentioned above, the immaterial aspect (form) of things (since material objects have form and matter) is abstracted by the intellect. The senses pick up the material object and the intellect considers the immaterial aspect of it. From this immaterial consideration one can know the universal nature of the thing. (Notice only on a realist account can this be done since nominalists deny natures exist.) The senses know the individual thing and the intellect abstracts to the universal nature. Knowledge (epistemology) is thus tied to metaphysics, i.e. the natures of things. The situation in contemporary epistemology often talks about knowledge without a discussion of metaphysics, or even the knower or thing known! Contemporary epistemology often simply talks about “knowledge” or “justification” in a vacuum, apart from the knower or thing known. But knowledge can’t happen without a knower knowing a thing! Thomists don’t have this problem.


In conclusion, Aristotelianism/Thomism does not have many of the typical problems in philosophy. This does not mean there are no specific problems or objections to Aristotelian/Thomistic thinking. But we do not suffer from these above problems, and I would argue our position is offers the best explanations to philosophical questions and interests.

Dr. Brian Huffling

Dr. Brian Huffling’s research interests include: Philosophy of Religion, Philosophical Theology, Philosophical Hermeneutics, and general issues in Apologetics and Biblical studies. See his personal blog here.


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