Introduction

In the domain of metaphysics, two of the most significant and enduring positions are Realism and Idealism. These two philosophical doctrines provide contrasting answers to fundamental questions about the nature of reality, the existence of the external world, and the relation between mind and world. Both traditions trace their origins to ancient philosophy and have evolved through various forms across centuries, deeply influencing the structure of Western and Eastern philosophical systems.

Realism in Metaphysics

Realism in metaphysics is the view that objects exist independently of the mind and our perceptions of them. It holds that the world has a definite structure and that this structure is mind-independent. This means that objects, properties, and relations exist whether or not any conscious being perceives them.

One of the earliest and most influential forms of metaphysical realism can be found in the work of Plato (427–347 BCE). Plato proposed the existence of Forms or Ideas—eternal, immutable entities that exist in a realm distinct from the material world. Although Plato’s theory is sometimes described as a form of idealism due to its emphasis on abstract entities, it is also realist because it affirms that these Forms exist independently of human thought.

In contrast, Aristotle (384–322 BCE) advocated a realism grounded in the empirical world. According to Aristotle, substances and their properties exist in the concrete world and can be known through sense perception and reason. For Aristotle, universals (such as “redness” or “humanness”) exist in particular things, and the task of metaphysics is to study being qua being, that is, being in its most general sense.

During the medieval period, metaphysical realism became a central topic of debate, particularly concerning the issue of universals. Realists like Thomas Aquinas (1225–1274) argued that universals exist in reality, either in things (in rebus) or in the mind of God (ante rem).

In the modern period, metaphysical realism was developed by philosophers such as René Descartes (1596–1650), who posited the existence of res extensa (extended substance, or material things) as distinct from res cogitans (thinking substance). Descartes held that the external world exists independently of the mind, though its precise nature must be established through rational inquiry.

In contemporary philosophy, metaphysical realism is often associated with the view that the world has a definite structure, independent of our conceptual schemes, theories, or linguistic practices. This view has been defended by philosophers such as Hilary Putnam (before he turned to internal realism) and Michael Devitt. Scientific realism, a form of metaphysical realism, asserts that the entities posited by our best scientific theories (such as electrons, quarks, and black holes) exist independently of our beliefs or observations.

Key features of metaphysical realism include:

• The existence of an objective reality that is independent of observers.

• The claim that truth consists in a correspondence between propositions or beliefs and mind-independent facts.

• The idea that knowledge aims to describe or represent this objective reality as accurately as possible.