In some Calvinist circles there's been a resurgence of interest in Thomism or Reformed Thomism. I don't share their enthusiasm. In this post I'll explain why.
II. Philosophical predilections
When it comes to philosophy and philosophical theology, I find metaphysics more interesting than epistemology. I take an interest in philosophical issues like the nature of time, personal identity, abstract objects (e.g. numbers, possible worlds), and thought-experiments.
I think it's important for Christians to have a considered religious epistemology, of course, but there's an obvious sense in which metaphysics is more fundamental than epistemology. Metaphysics supplies the objects of knowledge.
Because I find metaphysics more interesting than epistemology, I generally find "rationalist" philosophers more interesting than empiricist philosophers. "Rationalist" philosophers are far more inclined to delve into metaphysical questions than empiricist philosophers. That doesn't mean I generally agree with "rationalist" philosophers. But I prefer their orientation.
Because Aristotle is more down-to-earth than Plato, Aquinas is more down-to-earth than Augustine. I think Aquinas's interest in the empirical dimension of reality is a salutary corrective to Augustine. Nevertheless, Aquinas neglects philosophical issues that interest me. The nature world is fascinating, and frequently awesome, beautiful, and enjoyable. However, I also takes an interest in what lies behind the natural world.
As I've also said, developments in math, science, and philosophy have given us conceptual models and analogies that were unavailable to Aquinas.
III. Theological predilections
Unlike Aquinas, I'm not a medieval Catholic. Rather, I'm Protestant. That makes a difference. For instance, I start with the Bible and take that as far as I can. When the Bible doesn't address certain issues, I supplement Scripture with reason and empirical evidence.
IV. Thomistic categories
i) Thomistic metaphysics is based on his categorial scheme. That's carryover from Aristotle's taxonomy, although Aquinas modifies it.
Aquinas's taxonomy comprises the transcendentals (being, truth, goodness, unicity); material, formal, efficient, and final causes; essence, existence; form, matter; potentiality, actuality; substance, accident; privation.
Moreover, some of these categories correspond to each other, viz.
ii) I think it makes sense to base metaphysics on categories. Categories are the most fundamental kinds of things. Metaphysics is concerned with what there is. So to that extent I'm sympathetic to Aquinas's program.
ii) There are, however, problems with his choices. There's nothing inherently or distinctively personal about any of his categories. They could all be impersonal entities or kinds of things.
iii) In Plato, there's a clear-cut distinction between form and matter. But in Aristotle and Aquinas, the form tends to dissolve in the concrete object.
iv) There's also the problem of "pure" forms (e.g. God, angels) that are not a form of anything. That's a throwback to Plato's theory. So the classification breaks down.
v) I think sufficient condition better captures the notion of efficient cause.
vi) What's the justification for classifying formal, material, efficient, and final causes as causes? What do they share in common that makes all of them causes? For instance, teleology is an important category, but why claim it's a causal category? Put another way, in what respect are these four very different categories causes?
vii) Thomistic epistemology is naturally related to Thomistic metaphysics. As I understand him, Aquinas doesn't think we have direct knowledge of particulars. Rather, we discern the form in the particular. But what's the justification for that restriction?
V. Deriving categories
i) A deeper problem I have with Aquinas's categorial scheme is how he arrives at that taxonomy. What's his source of information? What makes those categories to be the ultimate categories rather than some other categories? In the history of philosophy, different metaphysicians have drawn up different lists of categories.
How are humans in a position to know what are the ultimate kinds of things? How do we even get started in developing a theory of categories?
ii) From a Christian standpoint, God is the ultimate source of reality. God's nature, existence, and imagination constitute the source of what's actual or possible. Therefore, in developing a theory of categories, it makes sense to begin with God. In particular, to correlate our categories with the communicable and incommunicable attributes of God. To some degree, communicable attributes function like abstract universals.
iii) There are different ways to classify the divine attributes. One way is to use Scriptural terminology. Biblical usage is sometimes redundant. For instance, God's "justice" and God's "righteousness" are synonymous. Those are not two different attributes.
You also have overlapping attributes: Holiness overlaps goodness and transcendence. Wisdom overlaps goodness and knowledge. So a classification of divine attributes needs to consolidate Biblical usage.
iv) Another way to classify divine attributes is to translate Biblical terminology into philosophical nomenclature, viz. aseity, omnipotence, omniscience, impassibility, timelessness, spacelessness. In deriving metaphysical categories from divine attributes, that makes sense.
V. Categories as communicable/incommunicable attributes
Let's list the divine attributes, and correlate them to categories:
1. The Trinity
The Trinity has several properties:
v) Number (one, three)
vi) Symmetry (a category that combines ii-iv).
2. Timelessness & spacelessness
i) On the face of it, that seems to be apophatic. Negative theology. What God is not. God is not spatial (physical, material) or temporal.
If is, however, possible to lend positive meaning to timelessness and spacelessness. Consider an actual abstract infinite. That's a given totality. Complete. By contrast, time and space are limits. In that respect, this involves a distinction between finitude and infinitude. God's existence is complete. We might use the word plenity to designate the fullness of God's existence. That stands in contrast to creatures whose existence is subdivided into spatial and/or temporal parts.
We could designate aseity as a kind of metaphysical necessity. Necessary existence. That stands in contrast to contingent existence. That distinguishes God from creatures and events.
4. Truth and speech
i) Scripture makes truth a divine attribute. Likewise, Scripture ascribes speech to God. Arguably, speech is an economic attribute.
Truth and speech have certain properties:
It's arguable that truth is a property of thought or concepts. Truth inheres in minds.
i) Knowledge presumes mentality. Knowledge is a property of minds.
ii) Knowledge can include imagination. Conceiving possibilities, including unexemplified possibilities.
This involves causality. Will and power. The ability to exercise power. The ability to convert abstract possibilities into concrete realities. Possible worlds are ground in God's omnipotence and omniscience.
VI. A Christian categorial scheme
1. Based on (V), we can derive the following categories:
iv) Symmetry (relation, resemblance, variation)
v) Plenity (actual infinity)/limits (time, space)
viii) Abstract objects (e.g. number, universals, possible worlds, logic)
2. The point of this exercise is illustrative rather than exhaustive. I'm not attempting to generate a complete categorial scheme, but to present a strategy for how a Christian metaphysician could do so. And I think that has a sounder basis in philosophical theology than Aquinas's rather arbitrary set of categories. I'm not a Thomist, in part because I don't see the value of squeezing or stretching philosophical analysis into his categorial scheme.