Quine’s famous Pegasus problem illustrates a central philosophical challenge: How can we meaningfully talk about something that does not exist, such as the mythical horse Pegasus, without ontologically committing ourselves to its existence?
This problem is representative of a broader philosophical discussion regarding the relationship between language, thought, and reality. Traditional solutions have typically either proposed alternative forms of existence, such as Meinong’s non-existent objects or Plato’s separate realm of ideas, or strictly denied any form of existence to such objects, as exemplified by Quine’s ontologically parsimonious position. This text proposes a third alternative: a physicalist theory where ideas exist within the same unified physical reality, yet epistemologically distinct from physically manifested objects.
The aim of this post is to articulate and defend a physicalist ontology capable of recognizing the existence of ideas without resorting to a separate ontological domain. The goal is to resolve Quine’s Pegasus problem by enabling a coherent interpretation of existence claims regarding conceptual entities. Furthermore, the text seeks to clarify how a physicalist ontology can reconcile both ontological parsimony and a rich conceptual framework that acknowledges the significance of ideas and fictional entities.
Argumentation
The theory rests on three central theses:
- Unified and Physical: Everything that exists does so within a single physical world. This excludes the existence of a separate world of ideas or metaphysical dualistic solutions, such as Cartesian dualism or Platonic idealism. The theory emphasizes that there is no ontological difference between physically manifested phenomena and ideas, aside from the manner of their realization.
- Ideas as Emergent Patterns: Ideas are defined as emergent phenomena arising within physical systems, such as brains, language, and cultural artifacts. While ideas lack physical manifestation in a strict sense, they are nonetheless real, as physically anchored structures that can be indirectly observed through neuroscience, linguistics, and sociology.
- Epistemological Distinction of Existence: Existence can be understood in two epistemologically distinct ways within this ontological framework: physical manifestation and conceptual occurrence. This distinction is not ontological but refers to different ways of knowing and identifying entities within the same physical reality.
Applied on the Pegasus case
When we state “Pegasus does not exist,” the statement clearly targets the existence of Pegasus as a clear and unified physically manifested object which is directly observable through our senses. This assertion means there is no physical object directly corresponding to the idea of Pegasus. However, it is simultaneously true that Pegasus exists as an idea within human culture and thought, manifested in texts, artworks, and human imaginations. These cultural and neurological structures are entirely physical, meaning Pegasus has genuine existence, although not one that directly maps to a single, clear, manifested object occupying space and time.
Thus, the assertion of Pegasus’s non-existence is not paradoxical but rather clarifies an epistemological duality inherent in the concept of existence, within a unified physicalist ontology.
| Mode of Manifestation (Within One Physical Ontology) | Examples | Ontological Status | Epistemological Character |
|---|---|---|---|
| Physical | Horses, tables | Directly manifested objects occupying space-time | Observable through direct sensory experience |
| Conceptual (emergent, but physically anchored) | Pegasus | Emergent patterns within physical systems (e.g., brains, cultural artifacts)—not a separate realm | Indirectly known via interpretation, cultural discourse, etc. |
Possible Objections
One potential criticism of this theory is that it introduces a form of ontological pluralism, which might seem to undermine the clarity of physicalism. The theory responds by clearly specifying that this pluralism is strictly epistemological. This implies that different forms of existence do not represent different ontological domains but rather different ways of identifying and relating to entities within a single reality.
Another possible objection concerns the boundary between physical manifestation and conceptual existence. The theory can address this critique by arguing that this boundary need not be metaphysically exact but can instead be pragmatically and empirically defined. For example, the boundary between a literary character and a real person is practically clear, even if theoretically blurred.
A third possible critique relates to the treatment of abstract objects, such as mathematical entities. Here, the theory can propose that even these objects can be understood as conceptually realized within physical structures (e.g., brains and symbol systems), rather than as entities with separate existence.
Conclusion
The physicalist theory of ideas’ existence offers a robust and elegant solution to Quine’s Pegasus problem. By maintaining strict unified physicalism while recognizing epistemologically distinct forms of existence, the theory enables a coherent and practical handling of conceptual entities without falling into metaphysical excesses. It provides a solution that is both ontologically economical and conceptually rich, thereby opening avenues for further research on concept formation, philosophy of language, and emergence.