Nominalism vs Realism

by Zoltanous

Online discussions often simplify the complex debate between nominalism and realism. Some claim nominalism has fueled liberalism and eroded traditional society, citing nominalism as the reason for societal downfalls and occasionally supporting their view with philosophical reasoning. This interpretation, however, is biased and incomplete, leading to misjudgments and spreading of misinformation. To understand the debate, it's important to recognize that it cannot be neatly categorized into just "realism vs. non-realism." Where to begin in such a multifaceted conversation? In modern philosophical discourse, Platonism is associated with the concept of abstract objects that exist beyond sensory perception and have no causal impact on the empirical world. The existence of mathematical entities, for example, has been a contentious issue from the late 19th century onward. In the 20th century, a Platonist typically argued for the reality of such abstract entities. Figures like Gottlob Frege, Bertrand Russell, and Willard Van Orman Quine were prominent Platonists, although Quine, a physicalist, rejected non-physical entities and struggled to build a framework without abstract objects, in collaboration with Nelson Goodman.

Gottlob Frege and Bertrand Russell, as advocates of Platonism, recognized the existence of abstract entities. Classical Platonists, however, extend Plato's philosophy to include not just mathematical objects but also the concept of forms — timeless templates of tangible things that exist in their own right. Physical objects are seen as mere reflections of these forms, explaining the similarities among diverse instances. This broad philosophical stance is known as "realism," and it incorporates theories like essentialism and "natural kind realism." Russell, while a modern Platonist, did not fully embrace traditional realism. He diverged from ancient Greek assumptions, preferring a bundle theory where objects are simply clusters of properties, as opposed to the Greek substance theory which posited fundamental entities or substances carrying these properties.

Russell's modern Platonism, while acknowledging universals, represents a departure from the Greek notion of forms. He posited that objects are constructs of properties, and that universals are necessary to prevent an endless regress in explaining similarities — we recognize colors like "red" or "green" as universals that combine to form our perception of objects. Turning to Aristotle's contributions, we note that both he and Plato theorized about forms, but they envisioned them differently. For Plato, forms were distinct and separate from the physical examples that represented them, akin to distinct points along a non-overlapping line, clearly defined and discrete. Plato's view entails a distinct separation between the intelligible world of forms, the realm of mathematical objects, and the realm of sensible objects. However, there is no intersection between these domains. The world of forms serves as the foundation for the intelligibility of the sensible realm, yet remains fundamentally distinct from it. This perspective is sometimes referred to as extreme realism.

Aristotle's conception of forms markedly differs from that of Plato. While acknowledging forms, Aristotle sees them as inherent in their specific instances, not existing in a separate realm as Plato suggested. This viewpoint, known as moderate or immanent realism, influenced Christian philosophy, adapting to include the concept of divine ideas. Forms, in Aristotle's thought, are inseparable from matter; they combine to constitute substances, with matter providing potential and form conferring actuality. Aristotle also introduced the notion of divine conceptualism, distinguishing between particular forms, which are part of the substance, and universal forms, which exist in the mind of the Prime Mover, or God. This conceptual framework was later integrated into Christian theology, with divine ideas seen as the blueprint for creation.

The debate between nominalism and realism is complex and multifaceted. Realism has many shades, including mathematical realism and realism about natural kinds or essences. Even within essentialism, nuances exist between immanent and transcendent forms of realism. Modern philosophy, too, engages with these ideas. Saul Kripke, for example, has argued for the existence of essences, revisiting Aristotelian categories. The simplistic dichotomy of nominalism versus realism overlooks such intricacies. Identifying as a "realist" or "essentialist" without context is overly reductive. For instance, Willard Van Orman Quine, though a physicalist, is labeled a Platonist because of his stance on abstract objects, showing that the term "Platonist" can be quite broad. The historical and political narratives that hinge on this debate often simplify it, which can mislead and distort the philosophical discussions that have evolved over centuries. Among idealists like George Berkeley, nominalism prevailed, with a rejection of abstract essences. Understanding this complexity is crucial, and caution is advised when encountering oversimplified accounts of these philosophical debates.