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Ideas Have Consequences: Why the rise of nominalism is such a big deal

What is nominalism? It is the denial of the existence of universals. To be an anti-nominalist is to commit to holding some theory of universals while leaving room for debate about which particular account of universals is true. But what is a universal? To answer this question, let me tell you a story.

Myth and Reason

Our story begins on May 28, 585 BC. The Greek historian Herodotus informs us that on this day Thales of Miletus, a mathematician and astronomer, accurately predicted a solar eclipse. Aristotle, in Metaphysics, called him “the founder of this school of philosophy.” He was known as one of the “Seven Sages” of antiquity.

To his contemporaries, this prediction was an astonishing accomplishment. How was such a thing possible? The pre-Socratic philosophers from Thales down to Socrates all sought the answer to this question. And what made them different from all their predecessors is that they sought it in reason.

The ancient Near Eastern civilizations around Israel like those of Egypt and Mesopotamia were all mythological cultures. So were the Babylonian, Persian, Greek and Roman cultures that successively dominated the holy land up to the time of Christ. Mythological civilizations used religion to try to win the favor of the gods, who they saw as responsible for the structure and order of nature that made culture possible. All the myths began with eternal chaos as the state of the world and told the story of a hero-god who battled the chaos monster and established order by violence. This was why the crops grew and the flocks were fertile, and it was why natural disasters like volcanoes were held at bay. Religious rituals, including sacrifice and various forms of sympathetic magic, were key to keeping the gods happy and focused on doing their job so society could flourish.The search for a rational explanation for nature went on, however, until a genius emerged who brought together two streams of investigation that would form something new in human history: natural science. Click To Tweet

In mythological cultures, the idea that nature operated according to laws that could be known by human reason through observation and deduction was never seriously entertained. And even in Greece, philosophy was only ever the preserve of a few eccentric and learned people. It was never taken seriously by the culture as a whole and Greek drama continued to proclaim the myths that most people believed and Greek polytheistic religion flourished. In fact, philosophy often was seen as dangerous to society and as a denial of the gods, as Socrates was to discover.

Natural Science

The search for a rational explanation for nature went on, however, until a genius emerged who brought together two streams of investigation that would form something new in human history: natural science. Plato was very influenced by the number mysticism of the Pythagoreans, who saw in mathematics the clues to the secrets of the universe. But he was also influenced by the observation-based investigations of the pre-Socratics who sought to formulate laws of nature based on the observation of natural phenomena. Many mythological cultures had produced individuals who had been able to make predictions based on observation, but what made the quest initiated by Thales unique was that Plato developed a theory to explain why such predictions were even possible.

Plato saw that Heraclitus had a point in viewing all as flux and change. Is change not the fundamental reality we face in this world? But if that was the whole story, what accounts for the undeniable order and law-like activity we observe in the midst of this change? Why do horses never beget baby goats? Why does the process for making wine work consistently year after year? Why do we observe continuity in identity throughout the life cycle? Once I was a fetus, then a baby, then a child, then a teenager, then a young man, then a middle-aged man, then an old man and finally a corpse. Then they bury me and put the name I was given at birth on my headstone. What makes me, me, throughout all those many changes?The world of universals is the world of metaphysics (literally “above the physical.”) Click To Tweet

Plato invented a theory of universals. He created a “theory of everything” by which all the questions in the previous paragraph received a satisfactory answer. Things in the world have natures because they are composed of both matter and form. The form of a thing participates in universals, which Plato understood as “Forms” or “Ideas.” For example, there are many triangles in the world, but they are recognizable as triangles because they participate in the form of triangularity, which exists in an immaterial realm of permanence distinct from our material world of flux. So, a thing changes because it is part of the material world and it retains a consistent identity because it participates in the immaterial world. To know a thing’s nature is what it means to know it. The immaterial world is above the material world, which reflects it and is dependent on it. The world of universals is the world of metaphysics (literally “above the physical.”)


This was new. Metaphysics – the core of philosophy and the basis for natural science – was now a rival explanation to mythology. The Platonic tradition was born. Aristotle is not, as sometimes portrayed, the opposite of Plato in every way, although they had big disagreements about the nature of the forms. Aristotle denied the existence of a “Third Realm” of abstract objects and insisted that the forms are inherent in the things themselves. But he did not deny the necessity and reality of universals. For the next 800 years the tradition of Platonic philosophy continued as an intellectual tradition even though it never really dominated Greco-Roman culture, which continued to be mythological. The so-called “Neoplatonists” of Augustine’s day (like Plotinus) were direct descendants of this philosophical tradition, which by this time had absorbed some of the teachings of the Stoics.

There were other thinkers in Greco-Roman culture, but it is debatable whether they should all be called “philosophers” or not. The Epicureans were cultured hedonists. The Stoics were pantheists and certainly philosophers, but there also were the Sophists who taught that there is no truth and that the purpose of rhetoric is to exercise power over the assembly.Augustine believed that consistent Platonists should, naturally, become Christians as soon as they heard the Gospel. Click To Tweet

The dividing line between the Platonists and the others was a belief in the existence of universals and the power of the human intellect to know them. This is what made philosophy unique. Augustine criticized the Platonist philosophers of his day for compromising with the idolatrous worship of their day, which they did to avoid being accused of atheism. Augustine believed that consistent Platonists should, naturally, become Christians as soon as they heard the Gospel. In this belief, Augustine was echoing a long line of Christian writers going all the way back to Justin Martyr (AD 100-165), who saw Christianity as the fulfillment of the quest of the Platonic tradition.

Platonism Fulfilled

Neither Plato nor any of his successors during that 800-year period had successfully explained the true nature of God. None of them had a doctrine of creation such as we find in the Book of Genesis. None of them could explain the origin of the cosmos as ordered by God and none could tell a person how to know God. Christians believed, with good reason, that they could take the best of the Platonic tradition, including the idea of universals, and set it on a firmer foundation. Furthermore, Christians believed that the Platonists had no way to overcome the problem of sin and that the Gospel provided a way by which humans could be forgiven and regenerated so as to be able to enter into intimate friendship with God and know God personally. Knowing God and the doctrine of creation, they said, was the key to understanding why this world is as it is – why it has order and structure that can be discerned by the mind of human beings. God created by his Logos and then created humans in his image so that human reason matches the order of nature like a key fitting in a lock. This is why science is possible. Christianity does not deny metaphysics; it explains it and puts it on a firm foundation. Christianity is not anti-science; it actually is the best explanation for why the world is the kind of world that science can and does explore.Christianity is not anti-science; it actually is the best explanation for why the world is the kind of world that science can and does explore. Click To Tweet

Modern science developed in the Christian West because of the coming together of Platonic metaphysics and the Christian doctrine of God the Creator. Both elements are necessary to a complete and true philosophy. Observation of the law-like behavior of matter are described using the language of mathematics, which allows for the level of abstraction needed for the development of falsifiable experiments. Observation, data, hypothesis, experiment, results – all the aspects of the scientific method are based on the coming together of observation and mathematics, and they came together as the result of the genius of Plato. Christianity provides a fuller, richer account of creation and opens the way to knowing the God who created both the world and the human mind in such a way that knowledge of creation by humans is possible.

Why Nominalism Fails

Nominalism is the denial of the existence of universals. There are many theories of universals and there is room for debating the adequacy of these theories within philosophy. But once someone goes so far as to deny the reality of universals altogether, the foundations of knowledge are seriously compromised. This is what happened in the European Enlightenment in the late 17th and 18th centuries. Hume was a nominalist and the most significant implication of that fact for subsequent intellectual thought was his denial of the principle of causality. The principle of causality is fundamental to all real science. Without it, the line between science and magic blurs and science tends to get reduced to ideology.

Kant was spooked by Hume and the French Enlightenment into thinking that classical metaphysics had been refuted, so he attempted to reconstruct it on the basis of what he called his “critical philosophy.” What he attempted was the first of many anthropocentric philosophical systems that would take a myriad of shapes during the next 200 years. All post-Kantian philosophy moves the principle of order and structure from “out there” in the world to “in here” in the human mind. Human reason is the source and basis of the structure of the world. Hegel’s is the most far-reaching and comprehensive attempt to develop such a system and his influence on the modern world, including systematic theology, has been continuous and massive.All post-Kantian philosophy moves the principle of order and structure from “out there” in the world to “in here” in the human mind. Click To Tweet

There is no time in this essay to chronicle the degeneration of metaphysics into ideology and the rise of skepticism and relativism during the rest of the 19th and early 20th centuries. The dam did not really break in the sense of the release of philosophical relativism into the cultural bloodstream until the 1960’s. Then the sexual revolution, gender theory, Maoism, revolution and the attack on standards, morals and traditions came like a flood and the floodwaters have yet to start receding.

Ideas Have Consequences

It is crucial to see that what happened in the second half of the twentieth century was just the mainstreaming of ideas that had been percolating for centuries. The importance of Hume was not that he “discovered” nominalism, but that he convinced so many others that it was true. In his prescient 1948 book, Ideas Have Consequences, Richard Weaver wrote:

One may be accused here of oversimplifying the historical process, but I take the view that the conscious policies of men and governments are not mere rationalizations of what has been brought about by unaccountable forces. They are rather deductions from our most basic ideas of human destiny, and they have a great, though not unobstructed, power to determine our course. (3)

For Weaver, ideas have great power to shape human thinking and human action for either good or evil. To explain the evil ideas of his period, he continues:

For this reason I turn to William of Occam as the best representative of a change which came over man’s conception of reality at this historic juncture. It was William of Occam who propounded the fateful doctrine of nominalism, which denies that universals have a real existence. His triumph tended to leave universal terms mere names serving our convenience.

In our day we see the twisting, manipulation and torturing of words and their meaning by those who seek power over language as a means to power of other people. Weaver continues:

The issue ultimately involved is whether there is a source of truth higher than, and independent of man; and the answer to that question is decisive for one’s view of the nature and destiny of humankind.

For Weaver, only universals provide a truth that is higher than anything merely human. The question the Christian asks is: “Has God designed into creation norms or laws that human reason can only discover but never create or change?” For Christianity the answer is yes and the agreement of Platonic philosophy over the centuries has been the basis for cooperation. The rise of nominalism, however, eliminates philosophy as a partner in culture construction.Only universals provide a truth that is higher than anything merely human. Click To Tweet

It is often said that we live in a “post-metaphysical age.” Here is Weaver’s description of what that means:

The practical result of nominalist philosophy is to banish the reality which is perceived by the intellect and to posit as reality that which is perceived by the senses. With this change in the affirmation of what is real, the whole orientation of culture takes a turn, and we are on the road to modern empiricism.

For Weaver, the denial of “everything transcending experience” means “the denial of truth.” (4) Nature is no longer is understood as imitating a transcendent model; rather, it now is looked at as “containing the principles of its own constitution and behavior.” This describes the dominant way of thinking in the late modern West, and it explains our practical materialism and our practical atheism.

Surely one would necessarily conclude that an intellectual shift that produces materialism and atheism as the dominant forces in a formerly Christian culture is a very big deal indeed.

For Further Reading: The title of this piece is taken from the title of Richard Weaver’s classic, Ideas Have Consequences (University of Chicago, 1948) in tribute to its importance. In addition to that book, I highly recommend reading Lloyd Gerson’s monumental trilogy on Platonism. On William of Occam, see Michael Allen Gillespie’s, The Theological Origins of Modernity (University of Chicago, 2008). A more popular level account of nominalism can be accessed in Peter Kreeft’s, C. S. Lewis for the Third Millennium (Ignatius, 1994). On the importance of Platonism for science, see Pope Benedict XVI’s Regensburg Lecture, which can be found as an appendix in the book by James Schall, The Regensburg Lecture (Ignatius, 2007).

*This post was originally published in Dr. Carter’s Newsletter.

Craig A. Carter

Craig A. Carter is the author of Interpreting Scripture with the Great Tradition: Recovering the Genius of Premodern Exegesis (Baker Academic, 2018) and Contemplating God with the Great Tradition: Recovering Trinitarian Classical Theism (Baker Academic, 2021). He is currently writing a third volume in the Great Tradition trilogy on the recovery of Nicene metaphysics. Other upcoming projects include an introduction to Theology in the Great Tradition and a theological commentary on Isaiah. He serves as Research Professor of Theology at Tyndale University in Toronto and as Theologian in Residence at Westney Heights Baptist Church. His personal website is and you can follow him on Twitter.

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