Reality Without Metaphysical Excess: From Bundle Theory to States of Affairs

 

Reality Without Metaphysical Excess: From Bundle Theory to States of Affairs

One of the recurring tensions in metaphysics concerns the relationship between explanatory power and ontological commitment. Philosophers seek theories capable of explaining individuality, persistence, modality, necessity, and truth, yet they disagree about how much reality must be populated to achieve those explanations. Traditional Substance Metaphysics posits substrata underlying properties; David Lewis's modal realism populates reality with an infinite plurality of concrete possible worlds. By contrast, Bundle Theory and D. M. Armstrong's ontology of states of affairs attempt to explain reality through structures and relations rather than hidden entities. Although these debates are often treated separately, they share a common philosophical question: must metaphysical explanation appeal to entities beyond what is directly instantiated in the actual world?

I argue that the strongest metaphysical framework emerges from combining a sophisticated version of Bundle Theory with Armstrong's ontology of states of affairs. Together, they provide a parsimonious account of individuality, truth, modality, and the role of perception in grounding these structures, without appealing either to mysterious substrata or to Lewis's vast plurality of worlds. Once reality is understood as a network of structured states of affairs, both the substance theorist's substratum and Lewis's possible worlds become unnecessary. Reality is best conceived not as a collection of hidden bearers or infinitely many worlds, but as a structured system of actual relations among particulars and universals, shaped by the perceiving subjects that model them.

The attraction of Substance Metaphysics is intuitive. Ordinary experience presents us with objects possessing properties: apples are red, round, sweet, and heavy. The traditional substance theorist argues that these properties must belong to something. Properties cannot float freely; they require a bearer. Consequently, behind the observable qualities of an object lies a substance that possesses them. This intuition stretches from Aristotle through much of early modern philosophy. The substance serves two crucial explanatory functions: it explains unity, as an apple is a single thing because its qualities inhere in one substance, and it explains persistence through change, as the apple remains numerically identical despite alterations in its accidental properties.

Bertrand Russell identifies a similar tendency in The Problems of Philosophy. Although he questions naïve realism, he recognizes the impulse to infer an underlying reality behind sense-data (Russell 12). What we directly encounter are appearances, yet we naturally suppose these appearances are manifestations of something fundamental. The difficulty, however, is that the substratum itself appears unknowable. If every observable feature belongs to properties, the substance possesses no characteristics by which it can be known. It becomes a purely theoretical posit whose sole function is to support properties, leading to a circular explanation: a substance is that which bears properties, while properties are those things borne by substances.

Bundle Theory rejects this additional metaphysical layer. Objects are nothing over and above bundles of co-instantiated properties. The appeal of this theory lies in its ontological economy—an embodiment of Occam’s Razor. If every characteristic of an object can be explained through its properties, introducing a substratum is gratuitous. However, the theory confronts the Pincushion Problem: if properties are pins, where is the cushion holding them together? Critics argue that Bundle Theory cannot explain numerical distinctness in cases involving indiscernible objects. If two spheres consist of the same properties, how can the theory distinguish them? This criticism assumes that properties cannot themselves provide unity.

Armstrong offers a powerful alternative through his ontology of states of affairs. For Armstrong, reality consists of particulars instantiating universals, and the fundamental unit of existence is the state of affairs (Armstrong, A World 1). The unity of an object need not arise from a hidden substance; it can arise from the relational structure binding properties together. By treating compresence as a primitive relation, the "cushion" becomes relational structure itself. This preserves the ontological economy of Bundle Theory while avoiding its incoherence. Furthermore, Armstrong provides a theory of truth: propositions are true because corresponding states of affairs exist. States of affairs function as truthmakers, grounding truth in actual reality rather than linguistic convention (Armstrong, A World 115).

While Armstrong grounds truth in actuality, David Lewis expands reality into an infinite plurality of concrete possible worlds. Lewis argues that a statement is possible if it is true in at least one possible world, reducing modal discourse to quantification (Lewis 2). The explanatory power of this framework is undeniable, but the ontological cost is extreme. Every way reality could have been corresponds to a concrete world that actually exists. Modal realism appears to explain possibility by replacing one mystery with countless realities. Lewis justifies this by arguing that theoretical utility outweighs ontological extravagance, yet many philosophers argue that explanation should proceed through the structure of actual reality rather than distant worlds (Lewis 4).

This debate necessitates a fourth point: the role of perception. If reality is a structured system of states of affairs, our access to this structure is mediated by the perceiving subject. Consensus unreality suggests that our models of the world—our "truthmakers"—are shaped by perceptual and conceptual framing. While the states of affairs exist independently, the way we categorize them into individuals is a function of our cognitive and perceptual architecture. Perception does not create the states of affairs, but it provides the relational lens through which we recognize them as "objects."

Reality is therefore best understood as a hierarchy where states of affairs provide the ontological grounding, while perceptual recognition provides the epistemic framework. This avoids the "observer-dependence" trap by maintaining that the states of affairs are actual, while acknowledging that our metaphysical "inventory" of the world is shaped by the perceiving subject. We do not require Lewis’s infinite worlds or the substance theorist’s hidden bearers to explain possibility or unity. We require only a disciplined analysis of actual, structured relations and the cognitive processes that model them.

The debates between Substance Metaphysics and Bundle Theory, and between Armstrong’s states of affairs and Lewis’s modal realism, are expressions of the same methodological conflict. The strongest answer emerges from combining a relational Bundle Theory with Armstrong's states of affairs, framed by an understanding of how perception models these structures. Such a view preserves explanatory rigor, respects ontological economy, and aligns with contemporary scientific thought. Metaphysical success lies not in multiplying what exists, but in understanding the structured relations—and our perceptual modeling of them—that constitute the world.

Works Cited

Armstrong, D. M. A World of States of Affairs. Cambridge UP, 1997.

Lewis, David. On the Plurality of Worlds. Blackwell, 1986.

Russell, Bertrand. The Problems of Philosophy. Oxford UP, 1912.