A Christian view of metaphysics (the fundamental nature of reality) contrasts with competing views from the history of philosophy. A survey of these views could easily fill a large book.[1] The following analyses sample and simplify some of the principal views that have most influenced the Western world.[2]
1. John M. Frame, A History of Western Philosophy and Theology (Phillipsburg, NJ: P&R Publishing, 2015).
2. India, China, Africa, and religious approaches such as Islam and Hinduism are outside our focus.
Criteria for Evaluation
We will evaluate each view from three perspectives.
- God. Does this view cohere with the existence of the Trinitarian God?
- Knowledge. Does this view give an adequate account of how we can know that something is true?
- Ethics. Does this view offer a solid basis for ethics?
Without an ethics that supports truth-telling and honesty, no view can sustain itself plausibly. Ethics is one point at which we can test a view according to Jesus’ principle “Thus you will recognize them by their fruits” (Matt. 7:20). Both actual behavior and proposals for ethical principles can be considered to be the “fruit.” Of course, the fruit has to be judged by biblical standards. If the fruit is bad, it shows that the root is bad, though it does not yet show specifically what went wrong with the root.
Philosophical Materialism
The most prominent metaphysical view today is philosophical materialism.[3] Philosophical materialism says that reality consists of matter and energy in motion. There are some variations among advocates of philosophical materialism. “Hard” materialism denies the existence of anything except matter and motion. “Soft” materialism says that while matter and motion are the foundation and the final explanation of all reality, complex combinations of matter can give rise to complex phenomena that we consider to be distinct—human beings, ideas, conscious experience, moral standards, and so on.
3. Frame, History of Western Philosophy, 52–54, 57–60; Daniel Stoljar, “Physicalism,” in The Stanford Encyclopedia of Philosophy, ed. Edward N. Zalta (Summer 2021), https:// plato.stanford.edu/archives/sum2021/entries/ physicalism/.
What is wrong with philosophical materialism?
God. God is not material. Either explicitly or implicitly, the various forms of materialism deny that God exists.
Knowledge. Materialism cannot give an account of itself, because the philosophical idea of philosophical materialism is not material. Alvin Plantinga makes a similar point in his extended interaction with materialistic Darwinism—a specific embodiment or type of materialism.[4] Of course, soft materialism can affirm a kind of existence of persons and ideas and abstract concepts. But how can we assure ourselves that our ideas of truth correspond to the world? Materialistic Darwinism promises only that we are constructed so as to enhance survival. But survival would appear to depend on the movements of molecules and nerve impulses and other material events. How do we know that these movements correspond to mental ideas in a way that makes these ideas true?
4. Alvin Plantinga, Where the Conflict Really Lies: Science, Religion, and Naturalism (New York: Oxford University Press, 2011).
Ethics. If matter is ultimate, then in the final analysis human beings are nothing more than clumps of matter. Ethical values, commitments, and choices are nothing more than personal preferences. For example, you prefer vanilla ice cream and your friend prefers chocolate. Likewise, you may prefer to help the old lady across the street, but your friend prefers to mug her. There is no transcendental set of values to which to appeal to adjudicate right actions from wrong ones, because a value is not a material thing. Ethical choices are merely the result of the motions of atoms and molecules, and atoms and molecules do not care about ethics! The natural endpoint for the ethics of philosophical materialism is the motto “Let us eat and drink, for tomorrow we die” (1 Cor. 15:32).
Pantheism
Next, consider pantheism. According to pantheism, all is “God.” Or, in panentheism, all is a part of God.
What is wrong with pantheism?
God. The Bible teaches a clear distinction between God, who is the Creator, and the world, which is created. Pantheism and panentheism have a kind of “god,” but it is not the God of the Bible.
Knowledge. Since each individual allegedly “is” God, it would seem that each individual unproblematically knows everything. If that is true, why are there differences in belief? Moreover, the collapse of distinctions among things in pantheism threatens to collapse the distinctiveness of statements about things in the world. If all is genuinely and thoroughly one, there is no room for distinctions. Each individual may indeed know everything that is to be known, but what is to be known is only one thing, which is a blank darkness.
Ethics. Pantheism cannot distinguish between good and evil because both are a part of the ultimate nature of reality.
Skepticism
Next, consider skepticism.[5] Skepticism denies that we can know the ultimate nature of the world. (This position is distinct from the more modest negative observation, “I do not currently know what is true.”) Since this denial is a kind of minimal theory about the nature of the world, we count skepticism as a metaphysical system.
5. Frame, History of Western Philosophy, 704–5.
What is wrong with skepticism?
God. Skepticism denies that God can make himself clearly known, as he has in fact done in nature (general revelation) and Scripture (special revelation).
Knowledge. Skepticism has trouble providing a foundation for itself. How can it be known that nothing ultimate can be known? That idea is self-defeating; it implies that we have investigated the world and drawn valid conclusions about it, the most basic of which is that we cannot know the world.
Ethics. Skepticism offers no basis for ethics.
Kantianism (with many variations)
Next, consider the philosophy of Immanuel Kant (1724–1804).[6] Kant argues that true metaphysics (knowing the fundamental nature of reality) is impossible. No one can know what Kant calls “the thing in itself ”—a thing as it really is apart from our perceptions—because all our knowledge of the world is filtered by our mental and perceptual categories of knowing. We know the content of our minds and our perceptions—not the reality of the world. Kant called “things in themselves” noumena and things as they appear to us phenomena. Thus, a rational metaphysical analysis of the thing in itself, as an ultimate constituent of reality, is impossible.
6. Frame, 251–70.
But Kant still offers us a system. Its starting point is epistemology, not the thing in itself. In his epistemology, Kant tries to establish what can and cannot be known, as well as the conditions for knowing anything. Thus, there is an ultimate structure within Kant’s epistemology. The ultimate structure is not the thing in itself, but Kant’s four categories of knowing —quantity, quality, relation, and modality and their respective twelve subcategories—which order our spatiotemporal perception of things.[7] The noumenal is distinguished from the phenomenal, and pure reason from practical reason. Whatever is phenomenal, what comes to us through our senses, comes to us already within a framework of the categories.
7. Frame, 258–60.
What is wrong with Kantianism?
God. Kant’s system is antagonistic to the Bible because in his system God belongs to the noumenal. God cannot directly reveal himself in the world through appearances. But this is precisely what he did at Mount Sinai, and what he did in the incarnation of Jesus Christ. Moreover, in Kant’s system, man virtually takes the place of the Christian God. He “creates” the world as we know it by the imposition of the categories that already exist in his mind.
Knowledge. Kant’s system cannot account for scientific knowledge based on the phenomenal, though it claims to offer an account. The laws of science are particular laws, not just a generic deduction from the principle of causality.[8] For example, Isaac Newton’s law of gravitation says that any two massive bodies exert attractive forces on each other. The magnitude of the force is proportional to the mass of each of the bodies and is inversely proportional to the square of the distance between them.[9] The direction of the force is to point directly toward the body that is the source of the attraction. This law is very specific. It is not merely a general statement that one thing can causally influence the motion of another. God enabled Newton to discover the law by interacting with a massive amount of data about physical motion. Newton did not impose the law merely by having a mind that thinks in terms of a principle of causality. For scientists to find these particular laws, the universe (the thing in itself!) must talk back to them, and not merely submit to a general principle already in their minds.
8. Vern S. Poythress, Logic: A God-Centered Approach to the Foundation of Western Thought (Wheaton, IL: Crossway, 2013), app. F1; also Vern S. Poythress, Redeeming Philosophy: A God-Centered Approach to the Big Questions (Wheaton, IL: Crossway, 2014), chap. 23.
9. Mathematically, F (force) = GMm/r2, where M and m are the two masses, r is the distance between them, and G is the “gravitational constant,” a universal value representing how strong the force of gravity is.
In addition, Kant’s system cannot easily give an account of how it is possible to know the philosophical claims that Kant himself makes. The claims in Kant’s book Critique of Pure Reason[10] seem to be rational claims about the fundamental nature of reality itself. But if the phenomenal is all that we can know (if we cannot know the world of “things in themselves”), then Kant’s claims in the Critique exceed the bounds of the phenomenal —the only realm that Kant claims that pure rationality can know.
Ethics. Kant’s ethics is based on the “categorical imperative”— universally binding, unconditional, absolute moral laws, for example: “You shall not murder.” In this respect, it fares better than many other philosophies. But it still has a weakness. It cannot motivate anyone who asks, “Why should I not be selfish and disobey the alleged categorical imperative that is part of my mind?” If the imperative is actually generated by the categories of the human mind, and does not owe its existence to the reality of God, who is our Creator, it is not clear why we may not simply choose to step away from its allegedly universal claims. So I just make myself an exception, whenever I need to. Who can say that I may not?
10. Immanuel Kant, Immanuel Kant’s Critique of Pure Reason, trans. Norman Kemp Smith (New York: St. Martin’s, 1965).
Postmodern Contextualism
Next, consider postmodern contextualism. There are many varieties and expressions of postmodernism. What we have in mind under the label postmodern contextualism[11] is only one aspect, which itself has variations. Roughly speaking, postmodern contextualism has at its heart the twin convictions (1) that claims to human knowledge always come within a linguistic, social, and cultural context, and (2) that this threefold context makes it impossible to know universal, transcendent truths. For the postmodern contextualist, truth is local to a particular culture or society; truth is culturally relative. More modest forms of contextualism might allow that sciences can arrive at universal truths, but a detailed look at the social contexts of sciences and the social flow of scientific claims to knowledge shows that sciences are the product of scientists, and scientists are social people. Scientific work is always socially situated. It always takes place within a social context, which includes other scientists, and often supporting staff and organizations who give grants and educational institutions. It cannot be immunized from the relativizing force arising from the analysis of social context.
11. Vern S. Poythress, In the Beginning Was the Word: Language—A God-Centered Approach (Wheaton, IL: Crossway, 2009), esp. chaps. 16, 17, apps. A, B, I.
What is wrong with postmodern contextualism?
God. The social situatedness of human knowledge allegedly means that God, if he exists, is inaccessible and unknowable. All that we access through human knowledge and human social relations belongs strictly to a human level. This view is opposed to the Bible, which claims to make God known to us.
Knowledge. Postmodern contextualism cannot easily account for itself. It builds its insights on linguistics and sociology, which make us more aware of the social influence of language and society. The appeal to social context extends to the social context of knowledge, as it is studied by the sociology of knowledge.[12] Linguistics and sociology, as scientific enterprises, are conditioned by their social contexts. Therefore, postmodern skepticism about accessing truth extends to the truths of linguistics and sociology. And therefore it extends also to the claims of postmodern contextualism itself. It offers no definitive insight, but only one more culturally limited claim.
12. Vern S. Poythress, Redeeming Sociology: A God-Centered Approach (Wheaton, IL: Crossway, 2011), apps. F, G.
Ethics. Ethics has no foundation except in culture, and cultures are plural. There is no appeal outside all cultures that could serve as a basis for condemning the abhorrent practices of some cultures, such as child sacrifice and racism.
Platonism
Next, consider Platonism.[13] Platonism has many forms. We will focus on Plato himself (and Socrates, who in the Platonic dialogues tends to serve as Plato’s mouthpiece). Plato says that the most ultimate constituents of the world are the forms: first and foremost, the form of the good, followed by the forms of justice, beauty, and holiness.
13. Frame, History of Western Philosophy, 63–70.
What is wrong with Platonism?
God. In the Timaeus, Plato allows a place for a “demiurge.” The demi- urge is a godlike being who looks at the eternal forms and then fashions particular things in imitation of the forms. In this system, the forms are superior to the demiurge. The demiurge is an inferior being, a counterfeit in comparison to the true God of the Bible.
Knowledge. Is Plato able to account for his own knowledge? In the famous dialogue Meno, Socrates explores the idea that we gain knowledge by reminiscence. This dialogue suggests that we know by remembering. We recover into consciousness the knowledge that the soul had by direct vision in its preexistent state before being in the body. But this picture puts man in the place of God. Man, as an eternally existing soul, has an eternity akin to God’s eternity, and one aspect of man’s eternity is eternal knowledge.
Platonism has another problem. The growth of modern science has undermined the plausibility of Platonism. Plato’s project was to achieve mastery by reason. Science has certainly grown through reason, but this growth has undermined confidence in human ability to discern the nature of the forms—and therefore the fundamental nature of the world—just by use of rationality. Scientists over the centuries have found that they have to pay attention to the world. They have to do experiments. They cannot just deduce from first principles how the world must be.
Philosophical use of reason might take the form of direct vision of the forms, or dialectical reasoning in dialogues (Socrates’ method), or discernment of the forms by intense reflection on instances of the forms. Whichever of the variations we consider within ancient Greek philosophy, the Greeks got it wrong. They got wrong the nature of the world. They thought that the heavenly world (sun, moon, and stars) included objects in motion, but that the objects themselves did not change. They thought that the earth was at the center of a system of heavenly spheres whose motion carried the sun, the moon, the planets, and the stars. They thought that the world was built up from four “elements”: earth, water, air, and fire.
Each of these conceptions of the world provides a partial truth, when treated as a perspective. But when a philosopher claims to arrive at an ultimate analysis and an ultimate layer of reality, he overreaches himself.[14]
14. Vern S. Poythress, Interpreting Eden: A Guide to Faithfully Reading and Under- standing Genesis 1–3 (Wheaton, IL: Crossway, 2019), 77.
Ethics. Plato also has problems in ethics. The proposals for government in the Republic, which are summarized in the early part of the Timaeus, involve what, from a Christian point of view, are unethical practices.
Aristotelianism
Next, let us consider the views of Aristotle (384–322 b.c.),[15] Plato’s student. Aristotle differed in a major way from his teacher. Aristotle taught that the forms manifested themselves in the objects in the world, instead of objects in the world being defective copies of the forms, as Plato taught. For Plato, the forms belonged to a transcendental, invisible realm; for Aristotle, they belonged to the world of things. Each individual horse, for example, is composed of form and matter. The form is the form of a horse, which distinguishes horses from other animals; the matter is the distinct material in the composition of the particular horse, matter that differentiates this horse from all the other horses.
15. Frame, History of Western Philosophy, 70–77.
What is wrong with Aristotelianism?
God. Aristotle in his book Metaphysics discusses a godlike being, the “Prime Mover,” who is also called “the Good” and “Mind” and “God.”[16] Unfortunately, this Prime Mover is not the God of the Bible. He/it is eternal, but there are forty-seven or forty-nine other unmoved movers, all of which are eternal. None of them is the creator, but only a causal starting point for the eternal motions of eternal heavenly bodies.
16. Vern S. Poythress, The Mystery of the Trinity: A Trinitarian Approach to the Attributes of God (Phillipsburg, NJ: P&R Publishing, 2020), chap. 25.
Knowledge. Like Plato, Aristotle has confidence in the ability of human philosophy to sound out the nature of reality by rational reflection. The achievements of modern science have shown the failure of this kind of rational confidence.
Ethics. The Prime Mover has a loose connection with ethics. Aristotle thinks that the Prime Mover moves other entities because the entities desire the Prime Mover as the final Good. But the Prime Mover is thought thinking itself: “its thinking is a thinking of thinking.”[17] It is empty as a source of ethics. At a practical level, ethics is related to the purposes of the things in the world. According to Aristotle, each thing, whether a human being, an animal, or a plant, has a purpose, namely, to develop its potential into actuality. The purpose is inherent in each thing. This view is contrary to the Christian view, according to which ethics rests on the character of God and is guided by what God says (as in the Ten Commandments).
17. Poythress, 286; Aristotle, Metaphysics, Loeb Classical Library (Cambridge, MA: Harvard University Press; London: William Heinemann, 1962), 1074b33–35, XII.ix.4.
The Use of Plato and Aristotle in Christian Theology and Philosophy
The deficiencies in Plato’s and Aristotle’s teaching about God are serious; they amount to blasphemies because they fail to show reverence for the true God and because they attribute some of his attributes to things other than God. In addition, their ethical views are defective. How could Christians have imagined that it was safe to adopt other ideas from these non-Christian philosophies? In the end, we may not know. But three possible reasons suggest themselves.
First, because of common grace there are fragmentary insights of truth in Plato and Aristotle and in all the other philosophers. That makes it attractive to adopt whatever in them seems plausible. For example, each individual horse belongs to a larger “kind,” a natural kind, namely, the group of all horses. The commonalities belonging to all horses seem to be akin to a Platonic form or an Aristotelian form. Moreover, Aristotle’s system of categories is vaguely akin to the major grammatical categories in human languages. Substances can be designated by nouns, qualities by adjectives, active and passive motions by verbs, and so on. And the structure of human language, as a gift of God, is adapted to talking about the world.[18]
18. Poythress, Mystery of the Trinity, 218–19.
Second, for many Christian leaders in the first centuries, it may have seemed that there were no alternatives. One seemed to need some sort of assumptions about the deepest structure of the world in order to discuss some of the big theological questions, and what Plato and Aristotle had to offer in this regard seemed to be better than most.
Third, the adoption of some of their ideas seemed to work; it seemed to promote insight. We can see useful fragmentary insights, which are God’s gifts in common grace.
So it is worthwhile noting that criticisms can be lodged against even those aspects of Platonism and Aristotelianism that have found their way into Christian theology.[19] We cannot enter further into such criticisms here.
19. Poythress, pts. 5–6; Poythress, Logic, pt. 1.C.
Prayer
Our God, thank you for delivering us from vanity by instructing us in the Bible.
