Welcome to the first lesson of our module on metaphysics. In our previous discussions on epistemology, we grappled with the question of how we can justify our claims to knowledge, culminating in the fundamental challenge of the Problem of the Criterion. That problem forced us to question the very foundations of knowing. Now, we pivot from the question of how we know to the question of what there is to be known. What is the fundamental nature of reality?
Our journey into metaphysics begins with one of its most central debates. When you look at the world, you see objects: a desk, a computer, a star. The common-sense view, deeply embedded in our language and thought, is that reality is fundamentally composed of such enduring things or substances. But what if this is a profound mistake? What if reality is not made of things at all, but is rather a universal, dynamic flow of processes or events?
This lesson will introduce you to the crucial distinction between these two pictures of reality: substance ontology and process ontology. We will explore the core tenets of each view, their historical roots, and how this seemingly abstract philosophical debate has profound connections to the worldview suggested by modern physics.
1. Substance Metaphysics: A World of Things
The traditional and perhaps most intuitive view of reality is called substance metaphysics. Its core idea is that the world is populated by individual, self-subsisting entities—substances—which have properties and undergo change, but are fundamentally distinct from those properties and changes.
Aristotle is the key architect of this view. For him, a substance (ousia) is the ultimate subject of predication. It's the "this" that possesses qualities (e.g., this electron has a negative charge) and persists through change (e.g., the water becomes hot, but it is still the same water). A substance is a compound of form (morphē) and matter (hylē). The matter is the underlying "stuff" or substratum that persists, while the form gives the substance its identity and structure.
In this framework:
- Things are primary: Reality is an inventory of objects or substances.
- Change is secondary: Change is something that happens to substances. The substance itself endures.
- Persistence is key: An object maintains its identity over time by virtue of some enduring core or essence.
This view maps cleanly onto the world of classical mechanics, where you deal with point masses or rigid bodies that have fixed properties (mass, charge) and move through space over time. The particle is a substance.
However, this view faces difficult questions. What exactly is the underlying substratum that persists when all of a thing's properties change? How do we account for entities that seem to be defined by their activity, not by some static core? These challenges pave the way for a radically different approach.
2. Process Philosophy: A World of Becoming
Process philosophy inverts the traditional picture. It asserts that process, not substance, is the fundamental reality. What we perceive as stable, enduring objects are, in fact, relatively stable patterns or organized structures of events. The universe is not a collection of things; it's a flux of happenings.
The ancient Greek philosopher Heraclitus is the historical touchstone for this tradition, famous for the aphorism that one can never step into the same river twice. The river isn't a static container for water; its very being is the continuous process of flowing.
To get a clear overview of this fundamental opposition, let's turn to a video that outlines the core ideas of process philosophy, primarily drawing from the work of philosopher Nicholas Rescher.
Process Philosophy: A Different Metaphysical Approach
This video, "Process Philosophy: A Different Metaphysical Approach," provides an excellent introduction to the core claims of process thought and contrasts it directly with substance metaphysics.
Please watch the section Of Substance and Process, which lays out the two central premises of process philosophy and explains why it prioritizes activity, change, and novelty. Then, continue with the following section, The basic teachings, which lists the fundamental tenets of this worldview.
As the video explains, process philosophy argues that:
- Things cannot be understood without processes.
- Processes are more fundamental than things, and we can construct a view of reality based on processes alone.
This leads to a metaphysics where the primary categories are not substance and property, but rather becoming, change, activity, and emergence. "Things" are demoted to "loci of comparative (and transitory) stability within a manifold of continual change."
From your experience with physics and simulation, you can think of this distinction through the lens of a system like a barchan sand dune. In a substance view, a dune is a "thing," a pile of sand. In a process view, a dune is a self-sustaining pattern, a stable macroscopic structure that is constituted by the continuous flux of sand grains being transported by wind. The dune's identity lies in the ongoing process, not in any particular collection of sand grains, which are constantly changing. The dune is a verb masquerading as a noun.
3. Formalizing the Distinction
To give these ideas more philosophical precision, we can look at how process philosophy positions itself as a rival research paradigm to substance metaphysics. The Stanford Encyclopedia of Philosophy offers a rigorous formulation of this opposition.
This entry from the Stanford Encyclopedia of Philosophy provides a formal characterization of the two opposing views.
First, read the introduction to understand how process philosophy centers on becoming while traditional metaphysics focuses on static being. Start here. Next, read the first paragraph of section 1, "Process versus ‘Substance’," which defines process philosophy in opposition to substance metaphysics and introduces the idea that entities in a process view are individuated by what they do. Focus on this paragraph.
As the article notes, the key shift is from a focus on what there is (a static inventory) to what is occurring. Process philosophers replace the category of a static individual with a new basic entity individuated by its function or activity. This directly challenges the substance-based assumption that every process must be "owned" by a substance (e.g., the running of the man). Process philosophy allows for "unowned" processes, like a storm or economic inflation, to be fundamental entities in their own right.
4. Case Study: Alfred North Whitehead and Modern Physics
The most influential modern process philosopher is Alfred North Whitehead. His work is particularly relevant to you, as he began his career as a mathematician who collaborated with Bertrand Russell on the monumental Principia Mathematica. He turned to metaphysics later in life, motivated by the conviction that the scientific revolutions of the early 20th century—namely relativity and quantum mechanics—had rendered the old substance-based worldview obsolete.
The following lecture excerpt explains how Whitehead's scientific background informed his philosophical project.
A History of Philosophy | 61 Whitehead's Process Philosophy
This lecture by Dr. Arthur Holmes at Wheaton College, "Whitehead's Process Philosophy," connects Whitehead's metaphysical system directly to the physics of his time.
First, watch the segment detailing the influence of modern science on Whitehead's thought. Pay close attention to his interest in three developments in physics: electromagnetic field theory, quantum physics, and relativity. Next, watch the segment that introduces Whitehead's ultimate reality: creativity. This is his term for the fundamental process of the emergence of novelty.
Whitehead saw that physics was no longer about tiny, inert pellets of matter (substances) interacting in a void. Instead, it described a world of force fields, energy quanta, and events within a dynamic spacetime. Reality at its base seemed to be process-like.
- Electromagnetic fields: Not things, but regions of influence and potential activity.
- Quantum physics: Reality is composed of discrete packets of energy (quanta), which are fundamentally event-like, not tiny solid objects.
- Relativity: Space and time are not a passive, absolute container for things, but are themselves a dynamic participant in physical processes.
This led Whitehead to propose a metaphysics where the "final real things of which the world is made up" are not enduring substances but momentary events of experience he called "actual occasions" or "actual entities".
The Internet Encyclopedia of Philosophy gives a concise explanation of Whitehead's core metaphysical concept.
Please read the section titled Events, not Substances. This part explains how momentary "actual occasions" are the building blocks of reality and how enduring objects are just "societies" of these occasions.
In Whitehead's view, an enduring object like an electron is not a single, persistent substance. It is a "society," a serially ordered string of momentary "electron-occasions," each inheriting from its predecessor and flowing into the next. This creates the illusion of a single, continuous entity, much like the rapid succession of frames in a film creates the illusion of continuous motion.
Your own work in condensed matter physics provides powerful analogies. A phonon, a quantum of vibrational energy in a crystal lattice, is a quintessential process entity. It is a collective excitation, a patterned process, not a "thing" in the traditional sense. Similarly, the "self-organized criticality" you studied in bubble rafts is a property of the system's dynamic behavior—the avalanches of events—not a static property of any individual bubble.
Conclusion
Today we have explored the fundamental divide between two ways of conceiving reality. Substance ontology offers a familiar world of enduring things, while process ontology presents a more dynamic, event-based cosmos.
- Key Takeaways:
- Substance Ontology: The traditional view, where reality is fundamentally composed of static, enduring individuals (substances) that possess properties and undergo change. Change is secondary to the enduring thing. Think classical particles.
- Process Ontology: The view that reality is fundamentally composed of dynamic processes or momentary events. What we perceive as stable "things" are actually regular, repeating patterns within this flux. Think quantum field excitations or self-organizing systems.
- Alfred North Whitehead developed the most influential modern process philosophy, explicitly trying to create a metaphysics consistent with 20th-century physics. His "actual occasions" are the momentary "drops of experience" that constitute all of reality.
- This distinction forces us to re-evaluate our basic assumptions about what it means for something to exist and persist through time.
Preview of the Next Lesson:
This fundamental distinction sets the stage for many other metaphysical problems. Having asked "what is a thing?", we will next turn to a special kind of thing: a person. What makes you the same person you were ten years ago, given that nearly every physical and mental component of you has changed? In our next lesson, we will analyze competing accounts of personal identity over time, a puzzle where the clash between substance and process views becomes deeply personal and concrete.